Phân tích kỹ thuật với Ansys WorkBench 13 ( demo)

MỤC LỤC Trang

Chương I Sơ lược về phương pháp phần tử hữu hạn - FEM ......................................... 1

I. Các bước giải bài toán FEM .................................................................................... 1

II. Ví dụ ...................................................................................................................... 2

Chương II Tổng quan về phần mềm Ansys ..................................................................... 25

I. Khởi động Ansys .................................................................................................... 25

II. Giao diện Ansys ..................................................................................................... 26

III. Lưu trữ và hồi phục .............................................................................................. 28

IV. Cấu trúc bài toán trong Ansys ............................................................................... 28

V. Ví dụ 1 .................................................................................................................. 29

VI. Ví dụ 2 ................................................................................................................. 36

Chương 3 Tạo mô hình tính toán trong Ansys ................................................................ 42

I. Tạo mô hình trực tiếp trong Ansys .......................................................................... 42

II. Tạo mô hình với sự giúp đỡ của các phần mềm CAD ............................................. 78

Chương 4 Ứng dụng Ansys vào bài toán dầm - khung ................................................... 91

I. Dầm ........................................................................................................................ 91

II. Khung .................................................................................................................... 100

III. Khung không gian ................................................................................................ 108

IV. Dầm cong phẳng .................................................................................................. 115

Chương 5 Ứng dụng Ansys vào bài toán ứng suất .......................................................... 123

I. Nguyên lý st. Venant (The princible of st. Venant) .................................................. 123

II. Tập trung ứng suất do lỗ elip .................................................................................. 128

III. Ứng suất đặc biệt .................................................................................................. 134

IV. Bài toán ứng suất tiếp xúc hai chiều ...................................................................... 139

Chương 6 Phân tích dao động ........................................................................................ 150

I. Giới thiệu ................................................................................................................ 150

II. Phân tích mode cho thanh thẳng ............................................................................. 150

III. Phân tích mode dao động cho hệ thống giảm xóc của một ổ đĩa cứng ................... 156

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IV. Phân tích mode dao động của bàn máy dịch chuyển chính xác đơn trục sử dụng khớp

nối đàn hồi .................................................................................................................. 165

V. Phân tích mode dao động của hệ thống các khối vật thể và lò xo (Spring & Mass) . 173

VI. Phân tích dao động một mô hình đơn giản của một chiếc xe ................................. 180

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Chu:cmg 1 SCI lu:r;c vJ phu:cmg philp phdn tir hi1u hqn - FEM

Chu'dng 1 so LUOC VE PHUONG PHAp .

PHAN TU H Ctu HAN .

FEM

N hu dll bi~t, t~t ca cac bai toan ky thuat d~u c6 th~ bi~u di~n a d~ng cac phuang trinh toan hoc rna di~n hinh la cac phuang trinh vi phan lien k~t vai cac di~u ki~n bien. D6i vai nhung bai toan dan gian thi c6 th~ tim duQ'c lai giai chinh xac. Tuy nhien, h~u h~t cac bai to an c6 phuang trinh m6 ta va bien khao sat r~t phuc t~p, do d6 vi~c tim lai giai chinh xac cho bai toan g~p r~t nhi~u kh6 khan, rna d6i hiC kh6ng th~ giai duQ'c. D~ kh~c ph\lc nhung kh6 khan nay, thi nhi~u phuang phap s6 dll duQ'c ra dai. Trong nhung phuang phap s6 d6 thi n6i bac va thuang dung nh~t la phuang phap ph~n tu huu h~n (finite element method). Y tuang cua phuang phap ph~n tu huu h~n la chia vat th~ ra thanh mot tap huu h~n cac mi~n con (gOi la ph~n tu) li~n nhau nhung kh6ng lien k~t hoan toan vai nhau tren kh~p tung m~t bien cua chung. Truang chuy~n vi, bi~n d~ng, ung su~t duQ'c xac dinh tren tung ph~n tu. D~ng ph~n tu c6 th~ la thanh, d~m, gian, t~m, va, kh6i. Cac ph~n tu n6i k~t vai nhau qua cac nut.

I. cAc BUOC GIAI BAI ToAN FEM. 1. Rai r~c hoa mi~n khao sat (t~o luai cho ph~n tu): chia vat ra thanh nhi~u ph~n tu sao

cho tinh ch~t vat Ii cua m6i ph~n tu kh6ng thay d6i. N~u vat c6 bien d~ng phuc t~p thi chia cac ph~n tu a g~n bien sao cho that nhuy~n.

2. Xay dvng cac phuang trinh ph~n tu. 3. L~p ghep cac phuang trinh ph~n tu va tim ra rna tran do cung. 4. Khu cac di~u ki~n bien. 5. Giai M phuang trinh toan C\lC. 6. Tinh toan cac k~t qua.

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II. ViDV 1. Xet mot M giim nhu hinh 1.1. T~t ca cac thanh d~u lam b~ng g6 vai m6dun dan h6i Young

E = 1.9 X 106 (N/m2) va di~n tich m~t c~t ngang la 8 m2. Tinh ung su~t, chuy~n vi trong m6i

ph~n tu thanh gian va phan h,rc t~i hai g6i.

500N

2

Hinh 1.1

Giai bai toan nay se trai qua ba giai do~n (ti~n xu ly, giai, hau xu IY).

1) Giai do~n ti~n xu If. a) Nut va phdn tir:

500N

5

Xet m6i thanh gian la mot ph~n tu, di~m n6i chung l~i vai nhau la mot nut. Vi vay, M gian dll

cho co th~ chi thanh 5 nut va 6 ph~n tu nhu bi~u di~n a hinh 1.1. Sau day la bang th~ hi~n nut

va ph~n tu cua M gian:

Ph~n tu Nuti Nut} Goc e (1) 1 2 0

(2) 2 3 135

(3) 3 4 0

(4) 2 4 90

(5) 2 5 45

(6) 4 5 0

Bang 1.1

b) H ¢ s6 d9 dmg phdn tir: Ph~n tu (1), (3), (4) va (6) co cung chi~u dai, di~n tich m~t c~t ngang, m6dun dan h6i. Nen M s6 do cung tuang duang cho m6i ph~n tu duQ'c tinh:

k= AE = 8X(1.9XI06

)=4.22XI05 (N/m) L 36

(1.1 )

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Con ph~n tu (2) va (5) co h~ sf> do cung tuang duang:

k = AE = 8x(1.9xI06

) = 2.98xI05 L 50.9

(1.2)

c) Ma trq.n d9 dmg phdn tir:

d ph~n tu (1), (3) va (6) co goc B = 00 (nhu hinh 1.2).

L[o y

x OJ

i = 1 Ph~n tu (1) j=2

i = 3 Ph~n tu (3) j=4

i=4 Ph~n tu (6) j=5

Hinh 1.2

cos2 B sinBcosB -cos2 B -sinBcosB

[K](e) = k sinB cosB sin2 B -sinBcosB -sin 2 B

-cos2 B -sinBcosB cos2 B sinBcosB

-sinBcosB -sin 2 B sinBcosB sin2 B

cos2 (0) sin ( 0 ) cos ( 0 ) -cos2 (0) - sin ( 0) cos ( 0 )

= 4.22 X 105 sin ( 0 ) cos ( 0 ) sin 2 (0) - sin ( 0 ) cos ( 0 ) - sin2 (0)

(1.3) -cos2 (0) - sin ( 0 ) cos ( 0 ) cos2 (0) sin ( 0 ) cos ( 0 )

- sin ( 0) cos ( 0 ) -sin 2 (0) sin ( 0 ) cos ( 0 ) sin 2 (0)

• Ph~n tu thu (1):

1 0 -1 0 U1X

Diaphuang: [Kf) =4.22xI05 0 0 0 0 U1Y

-1 0 1 0 U2X

(1 A)

0 0 0 0 U2Y

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[ ](1G) 5

Toim C\lC: K = 10


4.22 0 -4.22 0 0 0 0 0 0 0 U1X

-4.22 0 4.22 0 0 0 0 0 0 0 U1Y

o o o o o o o o

o o o o o o o o

o o o o o o o o

o 0 0 0 0 0 0 U2X

o 0 0 0 0 0 0 U2Y

o 0 0 0 0 0 0 U3X

o 0 0 0 0 0 0 U3Y

o 0 0 0 0 0 0 U4X

o 0 0 0 0 0 0 U4Y

o 0 0 0 0 0 0 Usx

o 0 0 0 0 0 0 USY

1 0 -1 0 U3X

Dia phuang:[Kf)=4.22xl0S 0 0 -1 0

o 1

o 0 0 0 U4Y

o 0 0 0

o 0 0 0

o 0 0 0

o 0 0 0

o o o o

o o o o

o o o o

o 0 0 U1X

o 0 0 U1Y

o 0 0 U2X

o 0 0 U2Y

[ ](3G) 5 0 0 0 0 4.22

Toim C\lC: K = 10 o -4.22 0 0 0 U3X

o 0 0 0 0 o o o 0 0 0 -4.22 0 4.22 0 0 0 U4X

o 0 0 0

o 0 0 0

o 0 0 0


o o o

o o o

1 0 -1 0 U4X

Dia phuang: [K](6) = 4.22 X 105 0 0 -1 0

o 1

o 0 0 0 USY

o o o

o 0 0 U4Y

o 0 0 Usx

o 0 0 USY

(1.5)

(1.6)

(1.7)

(1.8)

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Chuong 1 SO' IU9'C v~ phuong philp phdn tir hfru h(;ln - FEM

0 0 0 0 0 0 0 0 0 0 U1X

0 0 0 0 0 0 0 0 0 0 U1Y

0 0 0 0 0 0 0 0 0 0 U2X

0 0 0 0 0 0 0 0 0 0 U2Y

Toim C1,lC : [K](6G) = lOs 0 0 0 0 0 0 0 0 0 0 U3X

0 0 0 0 0 0 0 0 0 0 U3Y

(1.9)

0 0 0 0 0 0 4.22 0 -4.22 0 U4 X

0 0 0 0 0 0 0 0 0 0 U4Y

0 0 0 0 0 0 -4.22 0 4.22 0 Usx

0 0 0 0 0 0 0 0 0 0 USY

• Ph~n tu thu (4): co goc e = 900 (nhu hinh 1.3) .

,..... . 4 o J=

L x

y Hinh 1.3

o i = 2

cos2(90) sin (90) cos (90 )

[Kt) = 4.22 x IOs sin (90) cos (90 ) sin2(90)

-cos2 (90) - sin ( 90) cos ( 90 )

- sin (90) cos (90) -sin2 (90)

-cos2 (90) -sin (90) cos (90 )

-sin (90) cos(90) -sin2 (90) (1.10)

cos2 (90) sin ( 90) cos (90 )

sin (90) cos (90) sin2 (90)

0 0 0 0 U2X

Dia phuO'ng: [K](4) = 4.22 x IOs 0 1 0 -1 U2Y

0 0 0 0 U4 X

(1.11)

0 -1 0 1 U4Y

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0 0 0 0 0 0 0 0 0 0 U1X

0 0 0 0 0 0 0 0 0 0 U1Y

0 0 0 0 0 0 0 0 0 0 U2X

0 0 0 4.22 0 0 0 -4.22 0 0 U2Y

Toim C\lC: [K](4G) = 105 0 0 0 0 0 0 0 0 0 0 U3X

0 0 0 0 0 0 0 0 0 0 U3Y

(1.12)

0 0 0 0 0 0 0 0 0 0 U4X

0 0 0 -4.22 0 0 0 4.22 0 0 U4Y

0 0 0 0 0 0 0 0 0 0 Usx

0 0 0 0 0 0 0 0 0 0 USY

• Ph~n tu thu (2): co goc e = 135° (nhu hinh 1.4) .

}=3

Hinh 1.4

cos2 (135) sin(135)cos(135)

sin (135) cos ( 135) sin 2 ( 135)

-cos2 (135) -sin(135)cos(135)

- sin (135) cos (135) - sin 2 (135)

-cos2 (135) -sin(135)cos(135)

-sin(135)cos(135) -sin 2 (135)

cos2 (135) sin(135)cos(135) (1.13)

sin (135) cos ( 135) sin 2 ( 135)

Dia phuang:

0.5 -0.5 -0.5 0.5 U2X

[K](4) = 2.98xl0s -0.5 0.5 0.5 -0.5 U2Y

-0.5 0.5 0.5 -0.5 U3X

0.5 -0.5 -0.5 0.5 U3Y

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•

1 -1 -1 1 U2X

= 1.49 X 105 -1 1 1 -1 U2Y

-1 1 1 -1 U3X

1 -1 -1 1 U3Y

Toim C\lC:

0 0 0 0 0 0

0 0 0 0 0 0

0 0 1.49 -1.49 -1.49 1.49

0 0 -1.49 1.49 1.49 -1.49

[K](2G) =105 0 0 -1.49 1.49 1.49 -1.49

0 0 1.49 -1.49 -1.49 1.49

0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 0 0

0 0 0 0 0 0

Ph~n tu thu (S): co goc e = 4So (nhu hinh 1.S) .

cos2 (4S)

sin( 4S)cos( 4S)

-COS2 (4S)

- sin ( 4S) cos ( 4S)

Hinh 1.S

sin( 4S)cos( 4S)

sin2 (4S)

-sin( 4S)cos( 4S)

-sin2(4S)

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

0 0 0

-COS2 (4S) -sin( 4S)cos( 4S)

-sin(4S)cos(4S) -sin2(4S)

cos2(4S) sin(4S)cos(4S)

sin(4S)cos(4S) sin2(4S)

(1.14)

0 U1X

0 U1Y

0 U2X

0 U2Y

0 U3X

0 U3Y

(1.1S)

0 U4X

0 U4Y

0 U5X

0 U5Y

(1.16)

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1 1 -1 -1 U2X

Dia phuang: [K](S) = 1.49 x 105 1 1 -1 -1 U2Y

-1 -1 1 1 Usx (1.17)

1 -1 1 1 USY

Toim C\lC:

0 0 0 0 0 0 0 0 0 0 U1X

0 0 0 0 0 0 0 0 0 0 U1Y

0 0 1.49 1.49 0 0 0 0 -1.49 -1.49 U2X

0 0 1.49 1.49 0 0 0 0 -1.49 -1.49 U2Y

[Kt2G) = 105 0 0 0 0 0 0 0 0 0 0 U3X

0 0 0 0 0 0 0 0 0 0 U3Y (1.18)

0 0 0 0 0 0 0 0 0 0 U4X

0 0 0 0 0 0 0 0 0 0 U4Y

0 0 -1.49 -1.49 0 0 0 0 1.49 1.49 Usx

0 0 -1.49 -1.49 0 0 0 0 1.49 1.49 USY

d) L&p ghep phdn tiro Ma tran do cung toim C\lC tim duQ'c b~ng cach l~p ghep cac rna tran do cung cua cac ph~n tu:

[K](G) = [K](IG) + [K](2G) + [K](3G) + [K](4G) + [K](SG) + [K](6G)

4.22 0 -4.22 0 0

0 0 0 0 0

-4.22 0 4.22 + 1.49 + 1.49 -1.49 + 1.49 -149

0 0 1.49-1.49 4.22 + 1.49 + 1.49 1.49

[K](G) = 0 0 -1.49 1.49 4.22+1.49

0 0 1.49 -1.49 -1.49

0 0 0 0 -4.22

0 0 0 -4.22 0

0 0 -1.49 -1.49 0

0 0 -1.49 -1.49 0

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0 0 0 0 0 U1X

0 0 0 0 0 U1Y

1.49 0 0 -1.49 -1.49 U2X

-1.49 0 -4.22 -1.49 -1.49 U2Y

-1.49 -4.22 0 0 0 U3X

1.49 0 0 0 0 U3Y

(1.19)

0 4.22 + 4.22 0 -4.22 0 U4X

0 0 4.22 0 0 U4Y

0 -4.22 0 4.22 + 1.49 1.49 Usx

0 0 0 1.49 1.49 USY

4.22 0 -4.22 0 0 0 0 0 0 0 U1X

0 0 0 0 0 0 0 0 0 0 U1Y

-4.22 0 7.2 0 -149 1.49 0 0 -1.49 -1.49 U2X

0 0 0 7.2 1.49 -1.49 0 -4.22 -1.49 -1.49 U2Y

0 0 -1.49 1.49 5.71 -1.49 -4.22 0 0 0 U3X = (1.20) 0 0 1.49 -1.49 -1.49 1.49 0 0 0 0 U3Y

0 0 0 0 -4.22 0 8.44 0 -4.22 0 U4X

0 0 0 -4.22 0 0 0 4.22 0 0 U4Y

0 0 -1.49 -1.49 0 0 -4.22 0 5.71 1.49 Usx

0 0 -1.49 -1.49 0 0 0 0 1.49 1.49 USY

e) Ap d(tt diJu ki¢n bien va tiIi tr9ng.

Di~u ki~n bien: nut 1 va 3 bi k~p ch~t nen U1X= U1y = U3X= U3y = O.

Tai trong: ngo~i h,rc tac d\lllg len nut 4 va 5 thea phuang th~ng dung: F 4y = -500 N va Fsy =

-SOON.

Tu nhfrng di~u ki~n bien thi phuang trinh do cung toan C\lC co th~ khu di hang thu nh~t, thu hai, thu narn va thu sau; cung vai nhfrng cot tuang ung. Tu do phuang trinh do cung toan C\lC

chi con rna tran 6 x 6 :

7.2 0 0 0 -1.49 -1.49 U2X 0

0 7.2 0 -4.22 -1.49 -1.49 U2Y 0

105 0 0 8.44 0 -4.22 0 U4X 0 = (1.21)

0 -4.22 0 4.22 0 0 U4Y -500

-1.49 -1.49 -4.22 0 5.71 1.49 Usx 0

-1.49 -1.49 0 0 1.49 1.49 USY -500

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2) Giai do~n giai. Giai phuang trinh (1.21), tim duQ'c:

{U2X : ~0.0035 m {U4X : ~.00118 m U2y - 0.0102 m U4y - 0.0114 m {

USX : ~.00240 m

USY

- 0.0195 m (1.22)

Ma tran chuy~n vi toim C\lC co th~ vi~t Iii.:

U1X 0

U1y 0

U2X -0.0035

U2y -0.0102

{v}= U3X 0

= m U3y 0

(1.23)

U4X 0.00118

U4y -0.0114

Usx 0.00240

USY -0.0195

3) Giai do~n h~u xu If. Sau khi tim duQ'c chuy~n vi cua cac nut thi co th~ ung d\lng d~ tim duQ'c cac k~t qua khac: a) Phan b;rc. Ph an h,rc duQ'c tinh:

{R}=[Kt {V}-{F} R1X 4.22 0 -4.22 0 0

R1y 0 0 0 0 0

R2X -4.22 0 7.2 0 -149

~y 0 0 0 7.2 1.49

R3X 0 0 -1.49 1.49 5.71 =

R3y 0 0 1.49 -1.49 -1.49

R4X 0 0 0 0 -4.22

R4y 0 0 0 -4.22 0

Rsx 0 0 -1.49 -1.49 0

ISy 0 0 -1.49 -1.49 0

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0 0 0 0 0 0 0

0 0 0 0 0 0 0

1.49 0 0 -1.49 -1.49 -0.0035 0

-1.49 0 -4.22 -1.49 -1.49 -0.0102 0

-1.49 -4.22 0 0 0 0 0

1.49 0 0 0 0 0 0

0 8.44 0 -4.22 0 0.0011 0

0 0 4.22 0 0 -0.0114 -500

0 -4.22 0 5.71 1.49 0.0024 0

0 0 0 1.49 1.49 -0.0195 -500

Su d\lllg ca.c phep tinh rna tran cho phuong trinh tren se tim duQ'c cac phan h,rc:

R1X 1500

R1y 0

~x 0

~y 0

R"x -1500 = N

R3y 1000

R4X 0

R4y 0

Rsx 0

RsY 0

b) N9i b;rc va zmg sudt philp.

Cac noi h,rc ph~n tu ix va JJX la b~ng nhau va nguQ'c chi~u:

{

ix = k( U;x -uJx )

i;x = k( UjX -u;x)

(1.24)

(1.25)

(1.26)

Trong cong thuc (1.26), Uix va Ujx la chuy~n vi t~i hai d~u nut cua ph~n tu a M dia phuong.

M6i quan M gifra chuy~n vi dia phuong va toan C\lC:

{v} = [T]{u} (1.27)

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uix cose sine 0 0 UiX

uiy -sine cose 0 0 UiY =

ujX 0 0 cose sine UjX

U jy 0 0 -sine cose UjY

Sau khi tinh duQ'c noi h,rc thi co th~ tinh duQ'c ung su~t phap cho m6i ph~n tu:

CJ=f A

(1.28)

(1.29)

Vi d\l, tinh noi h,rc va ung su~t phap cho ph~n tu thu (5). Nhfrng dfr li~u da co cua ph~n tu thu

(5): e = 45°, U2X = -0.00355 m, U2Y = -0.01026 m, Usx = 0.0024 m va Usy = -0.0195 m.

D~u tien, tinh chuy~n vi dia phuang cua nut 2 va 5:

u2x cos45 sin45 0 0 -0.00355

u2y - sin 45 cos45 0 0 -0.01026 = (1.30)

usx 0 0 cos45 sin45 0.00240

USy 0 0 - sin 45 cos45 -0.01950

thvc hi~n phep tinh rna tran ta tim duQ'c u2x = -0.00976 m va usx = -0.01209 m, th~ vao c6ng

thuc (1.27) va (1.28) se co duQ'c noi Ivc va ung su~t phap cho ph~n tu thu (5) l~n luQ'c la

696 N va 87 N/m 2 . Tuang W tim duQ'c noi Ivc va ung su~t phap cho cac ph~n tu con l~i.

II. ViDV 2. Su d\lng ph~n tu tam giac tuy~n tinh va tu giac tuy~n tinh d~ xac dinh chuy~n vi cua cac nut va ung su~t trong cac ph~n tu cua mot t~m mong duQ'c rang buoc chuy~n vi va chiu tac d\lng cua cac Ivc b~ m~t nhu hinh 1.6. Ngoai ra t~m mong con d~t trong m6i trnang nhi~t do thay d6i I1T = lODe. T~m mong co b~ day 0.5cm, m6dun dan h6i Young E=15x10~/cm2, M sf> Possion v =0.25 va M sf> gian nO' nhi~t ex = 6x 10-6

.

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600N/cm2

a u

M

2cm

Hinh 1.6

1. Dung ph An tIT tam gia tuy~n tinh (Linear Triangular Element). Chia t~m mong thanh hai ph~n tu tam giac nhu bi~u di~n a hinh 1.7. Toa do toan C\lC cua cac

nut duQ'c cho trong bang 1.2.

Nut Toa do nut Chuyen vi nut

1 (0,0) U X1 ' uY1

2 (2,0) U X2 ' UYo

3 (2,3) U X3 ' uY3

4 (1,3) U X4 ' uY4

Bang 1.2

y o---D 3 0---.02

1 u-____ v.::2'--_x_ 1u-----v 1

H~ to an C\lC H~ dia phuang

Hinh 1.7

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Chu:cmg 1 Sa lu:r;c vJ phu:cmg philp phdn tir hi1u hqn - FEM

a. Vec ta chuyJn vi cua nut Cr h¢ toim Cl;lC (global nodal displacement vector).

b. Di¢n tich (area).

U Yl

Di~n tieh eua m6i ph~n tu:

{

L1(1) =3em2

L1(2) = 3/2em2

U Y3

U }T em Y4

c. Ma trq.n thu(Jc tinh vq.t li¢u (material property matrix).

Gia su bili toan thuoe bili toan ung su~t ph~ng (v6i E = 15 xI 06 N/em2 vil v =0.25):

1 v 0

[D]=~ v 1 0 I-v

I-v o 0 2

d Ma trq.n hinh dqng phdn tir (element shape matrix).

• Ph~n tu thu nh~t:

!X(1) = x(1) - x(1) = x - x =-1 32 3 2 4 2 X(I) = X(I) - X(I) = x - x =-1

]3 I 3 I 4

x(1) = x(1) -x(1) = x -x = 2 21 2 I 2 I

[ UI 0 (I) 0 (1)

o ]l-3 0 3 Y23 Y31 Y12

[B(I)J=~ 0 (I) 0 (I) 0 x~~) = ± 0 -1 0 X32 x]3 2.L1 (1) (I) (I) (I) (I) y(1) -1 -3 -1 X32 Y23 x]3 Y31 X21 12

• Ph~n tu thu hai:

y(2) = y(2) _ /2) = Y _ Y = 0 23 2 3 3 4 X(2) = X(2) _X(2) = x -x =-1 32 3 2 4 3

y(2) = y(2) _ /2) = Y _ Y = 3 31 3 I 4 2 X(2) = X(2) - X(2) = x - x = 1 ]3 I 3 2 4

y(2) = y(2) _ /2) = Y _ Y =-3 12 I 2 2 3 X(2) = X(2) _X(2) = x -x = 0 21 2 I 3 2

[ 1'1 0 (2) 0 (2)

2;}~l ~ 0 3 0 -3 Y23 Y31 YI2

[B(2)J=~ 0 (2) 0 (2) 0 -1 0 1 0 X32 x]3 2.L1 (2) (2) (2) (2) (2) /2) -1 0 1 3 0 X32 Y23 x]3 Y31 X21 12

0 0

-1 0

3 2

~J

(1.31)

(1.32)

(1.33)

(1.34)

~J (135)

(1.36)

(1.37)

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ChU01lg 1 SO' lw;rc v~ phUV11g philp phdn tir hfru hqn - FEM

Tu do:

-48 -12 -6

1 l16 ~J ~ l~O -4 -16 -18

[BI'i JrD] ~~l ~ 0 3 0 0 4

~ 106

~ 48 12 -6

-1 0 -1 0 16 (l.38) -4 -16 18

-1 ,., -1 3 2 0 -.)

0 0 12

8 32 0

0 0 -6

[ BPI J [D] ~il ~l or l16 ~J~ l~' -4 -16 0

0 3 0 -3 4

o 106 4 48 12 6

-1 0 1 0 16 (l.39) 4 16 18

0 1 3 0 -3 0 0 -48 -12 0

0 0 -18

e. Ma tnj,n a9 dmg phdn tir (element stiffness matrix).


Ii = 11 Ij=21 Ik = 41

75 15 -69 -3 -6 -12

15 35 3 -19 -18 -16

[k(l)] = tLl(I) [B(I)J [D][ B(l)] = \~ -69 3 75 -15 -6 12 (1.40)

-3 -19 -15 35 18 -16

-6 -18 -6 18 12 0

-12 -16 12 -16 0 32

• Ph~n tu thu hai:

Ii = 21 Ij=31 Ik=41

6 0 -6 -18 0 18

0 16 -12 -16 12 0

[ k(2) ] = tLl(2) [B(2) J [D][ B(2) ] = \~ -6 -12 150 30 -144 -18 (1.41)

-18 -16 30 70 -12 -54

0 12 -144 -12 144 0

18 0 -18 -54 0 54

f Vector It;rc cila m6i ph6n tir (element load vector).

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{p~)}=tTX1~1-4{1 0 0 0 lOrN

{p~)} = t ~2~3-4 {o 0 0 1 0 1 r N

(1.42)

V6'i t = 0.5cm, Txl = 1200 N/cm2, Ty2 = -600 N/cm2 , ~-4 = .J12 +32cm va L3- 4 = lcm thi

vector h,rc ph~n tu tr6' thanh:

{{p~)} = 30000 {I 0 0 0 1 Or N (1.43)

{p~)}=-150{1 0 0 0 lOrN

g. Vector b;rc nhi¢t cua m6i phdn tir (thermal load vector).

Bi~n d~ng ban d~u (initial strain) do SlJ thay d6i tu nhi~t do (I1T= lODe, ex = 6x 10-6):

{e*}={aI1T al1T or =10-6 {60 60 or (1.44)

Vector IlJc nhi~t cua m6i ph~n tu:

{{p~:)}=tl1(1)[B(1)J[D]{e*}={-900 -300 900 -300 0 600}N

{p~:)}=tl1(2)[B(2)J[D]{e*}={0 -300 900 300 -900 O}N

h. Bi~n d6i ma trq.n d(J dmg, vector b;rc va vector b;rc nhi¢t vJ dqng toan Cl;lC.


ill ~ ill [1] 75 15 -69 -3 0 0 -6 -12

15 35 3 -19 0 0 -18 -16

-69 3 75 -15 0 0 -6 12

[k(l)] = \~ -3 -19 -15 35 0 0 18 -16

0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0

-6 -18 -6 18 0 0 12 0

-12 -16 12 -16 0 0 0 32

{p~)} = 30000 {I 0 0 0 0 0 1 OrN

{p~:)}={-900 -300 900 -300 0 0 0 600rN

• Ph~n tu thu hai.

(1.45)

(1.46)

(1.47)

(1.48)

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Chu:cmg 1 SCI lu:r;c vJ phu:cmg phap phdn tir hi1u hqn - FEM

ill ~ @] @] 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0

0 0 6 0 -6 -18 0 18

[k(2)] = \~ 0 0 0 16 -12 -16 12 0 (1.49)

0 0 -6 -12 ISO 30 -144 -18

0 0 -18 -16 30 70 -12 -S4

0 0 0 12 -144 -12 144 0

0 0 18 0 -18 -S4 0 S4

{p~)}=-IS0{1 0 0 0 0 1 0 lrN (1.S0)

{p~:)}={O 0 0 -300 900 300 -900 OrN (1.S1)

l. C(mg cac ma trqn d(J dmg, vector b;rc va vector b;rc nhi¢t.

75 15 -69 -3 0 0 -6 -12

15 35 3 -19 0 0 -18 -16

-69 3 (75 +6) (-15+0) (0-6) (0-18) (-6+0) (12+18)

K = Ik(e) = 106 -3 -19 (-15+0) (35+6) (0-12) (0-16)

e~l 12 0 0 (0-6) (0-12) (0+150) (0+30)

(18+12) (-16+0) (1.S2) (0-144) (0-18)

0 0 (0-18) (0-16) (0+30) (0+70) (0-12) (0-54)

-6 -18 (-6+0) (18+12) (0-144) (0-12) (12+144) (0+0) -12 -16 (12+18) (-16+0) (0-18) (0-54) (0+0) (32+54)

300JIO -900

-300

900 2 -300-300

{p}= L({P~)}+{p~:)})= N e~l 900

(I.S3)

-IS0+300

300JIO -900

-IS0+600

Tu d6 phuang trinh M th6ng toan C\lC (global system of equation) nhu sau:

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[K]{V} = {p}

75 15 -69 -3 0 0 U

-6 -12 Xl 30000 -900

15 35 3 -19 0 0 -18 -16 U Yl -300

-69 3 81 -15 -6 -18 -6 30 U X2 900

106 -3 -19 -15 41 -12 -16 30 -16 U Yo -600 (1.54)

<=>- x = 12 0 0 -6 -12 150 30 -144 -18 U

X3 900

0 0 -18 -16 30 70 -12 -54 U 150 Y3

-6 -18 -6 30 -144 -12 156 0 U 30000 -900

X4

-12 -16 30 -16 -18 -54 0 86 450 uY4

K~ ti~p, khfr cac di~u kien bien (u = 0, u = 0, u = 0, u = 0) thi: . h ~ Yo ~

75 0 -6 -12 u Xl 30000 -900

106 0 70 -12 -54 u 150 Y3 (1.55) <=>- x =

12 -6 -12 156 0 u 30000 -900 X4

-12 -54 0 86 u Y4

450

Giai phuang trinh (1-55):

u Xl 0.0000357839

u 0.000157003 Y3 (1.56) = cm u 0.0000171983

X4

u 0.000166367 Y4

2. Dung ph An tIT tIT giac tuy~n tinh (Linear Quadrilateral Element). Chia t~m mong thanh mot ph~n tu tu giac nhu bi~u di~n a hinh 1.8.a. Toa do toan C\lC cua cac nut duQ'c cho trong bang 1.3.

Nut Toa do nut Chuy~n vi nut

1 (0,0) U XI ' uYI

2 (2,0) U X2 ' UYo

3 (2,3) U X3 ' uY3

4 (1,3) U X4 ' uY4

Bang 1.3

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Chu:cmg 1 Sa lu:r;c vJ phu:cmg philp phdn tir hi1u hqn - FEM

0---03

(e)

2 Io-______ ~~--~x~ ___ -r. '1 = - 1

~=I

a) b)

Hinh 1.8

Ham d~ng cua ph~n tu tu giac (nhu hinh I.8.b) duQ'c dinh nghla b~ng cac sf> h~ng cua toa do

trong Him:

v6'i p = 1, 2, 3, 4

trong d6: I;p va '1p bi~u di~n toa do cua cac dinh nut trong toa do W nhien. V6'i:

~] = - 1, rh = -1

~2 = 1, rh =-1

~3 = 1, 1"h = 1

~3 = -1, 1"h = 1

Yay:

8N] = _ ~ (1-1] ) 8~ 4

8N] = -~(I-~) 81] 4

8N2 = ~ (1-1] ) 8N3 = -~(I +~) 8~ 4

& 81] 4

8N3 _ 1 (1 ) --- +1] 8~ 4

8N4 =~(1+~) 81] 4

8N4 = _ ~ (1 + 1] ) 8~ 4

8Ns =~(1-~) 81] 4

a. Vec ta chuyJn vi cua nut Cr h¢ toan Cl:lC (global nodal displacement vector).

(1.57)

(1.58)

(1.59)

(1.60)

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Ma tran Jacobian:

ax ay ~ [t(3-~) ~l

-

[J] = a~ a~

ax ay -(1-~)

a17 a17 4

Dinh thuc rna tran Jacobian:

II axay axay 3

~ J = a~ a17 - a17 a~ =8(3- 17 )

Ma tran Jacobian nghich dao (inverse of the Jacobian matrix):

ay

[Jr =~ a17 IJI _ ax

a17

ay a~

ax a~

=

4 0 (3-17) 2(1-~) 2 3(3-17) 3

vai p = 1, 2, 3, 4

(1.65)

(1.66)

(1.67)

(1.68)

(1.69)

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d. Ma trqn hinh dqng phdn tir (element shape matrix).

Tu cong thuc (1.59) thi:

aNI = _ (1 -lJ ) ax (3-lJ)

aN2 _ (l-lJ) ax - (3 -lJ)

aN3 _ (1 +lJ) ax - (3 -lJ)

aN4 = (l+lJ) ax (3-lJ)

Ma tran hinh d~ng ph~n tu:

aN] ax

o

&

aN2

ax

o

o

aNI 1 (l-~n =

ay 3 (3-lJ)

aN3 ( 2 + ~ -lJ ) =

ay 3(3-lJ) aN4 _ (1 + 2~ -lJ) By - 3(3-lJ)

aNs _ 2 (1-~) ay -3(3-lJ)

o

o

aN4

ax

o

o

aN] aN] aN2 aN2 aN3 aN3 aN4 aN4

By ax ay ax ay ax ay ax

(l-lJ) (3-lJ)

o (l-lJ) (3-lJ)

o

o _!(1-~) 3 (3-lJ)

o (2+~-lJ)

3(3-lJ) (l-lJ) (3-lJ)

(l+lJ) (3-lJ)

o

(1 + 2~ -lJ) 3(3-lJ)

(2+~-lJ)

3(3-lJ)

o

(1+2~ -lJ) 3(3-lJ) (l+lJ) (3-lJ)

(l-lJ) (3-lJ)

(l+lJ) (3-lJ)

o

o

2 (1-~) 3 (3-lJ)

(l+lJ) (3-lJ)

(1.70)

(1.71)

(1.72)

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e. Ma trqn thu(Jc tinh vqt li¢u (material property matrix).

Nhu cong thuc (1.33) thi ta co:

1 v 0

[D]=~ v 1 0 I-v

I-v o 0 2

f Ma trqn d(J dmg phdn tir (element stiffness matrix) TIl T

[k(e)]= f [B(e)] [D][B(e)]dV=tf f[B(e)] [D][B(e)]IJld~d17 V(e) -1-1

2 2 T

~ tL: L: WiW j [B(e) (~i,17;)] [D][ B(e) (~i' 17;) ]IJ( ~i'17;)1 i=1 j=1

trong do:

• Wi vii. Wj Iii. trong sf>

• ~i vii. 17j Iii. cac di~m tich phan cua cong thuc tich phan Gaussian.

V6'i ph~n tu tu giac tuy~n tinh thi chi dn l~y tich phan hai di~m, nen:

• WI = w2 = 1

{¢, ~Jl; ~-1IJ3 •

~2 = 172 = 11 -Ii

Ma tran do cung:

4.8666 0.76713 -4.3666 0.23287

0.76713 2.3545 0.73287 -1.0211

-4.3666 0.73287 5.3666 -1.7329

G [k(e)] =106 = 0.23287 -1.0211 -1.7329 3.6878

-2.7668 -0.96574 2.2668 -0.034264

-0.96574 -1.1244 -0.53426 -0.20891

2.2668 -0.53426 -3.2668 1.5343

-0.034264 -0.20891 1.5343 -2.4578

(1.73)

(1.74)

(1.75)

(1.76)

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-2.7668 -0.96574

-0.96574 -1.1244

2.2668 -0.53426

-0.034264 -0.20891

6.9663 0.56853

0.56853 3.5845

-6.4663 0.93147

0.43147 -2.2512

g. Vector b;rc cila phdn tir (element load vector).

{p~)J = t 1.::1~1-4 {I 0 0 0 0 0 1 Or N

TL { (e) } = t y2 3-4 {O 0 0 0 0 1 0 I}T N PT2_3 2

2.2668

-0.53426

-3.2668

1.5343

-6.4663

0.93147

7.4663

-1.9315

-0.034264

-0.20891

1.5343

-2.4578

0.43147 (1. 77)

-2.2512

-1.9315

4.9178

(1.78)

vai t = 0.5cm, Txl = 1200 N/cm2, Ty2 = -600 N/cm2 , ~-4 = .J12 +3 2 cm va L3- 4 = lcm thi

vector h,rc ph~n tu tr6' thanh:

f{P~)J = 300v1O {I 0 0 0 0 0 1 Or N

H p~;,} = -150 {o 0 0 0 0 1 0 1 r N

Vi vay h,rc t6ng cong:

(1.79)

{p~)}={p~)J+{p~;,}={300v1O 0 0 0 0 -150 300v1O -150r N (1.80)

h. Vector b;rc nhi¢t cila phdn tir (thermal load vector). lIT

{p~~)}=tf f[B(e)] [D]{8*}IJld~d17 -1-1

2 2 T

~ tLLwiW j [B(e) (~i,17;)] [D]{8*}IJ(~i,17;)1 i=1 j=1

= {-900 - 300 900 -600 900 300 -900 600} N (1.81)

l. T6ng hr;p vector b;rc.

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3 ooJIO - 900

-300

900

-300-300

900

-150+300

3 ooJIO - 900

-150+600

N

n) L&p ghep va giiti phu:cmg trinh phdn tiro

Saukhil~pghepvakhfreaedi~uki~nbien(u =0, U =0, U =0, U =O)thi: Yl X2 Y2 X3

4.8666 -0.96574

106 -0.96574 3.5845

2.2668 0.93147

-0.034264 -2.2512

Giai phuang trinh (1.83)

UXI 0.0000307806

uY3 0.000150801 = em

U 0.0000222016 X4

U Y4

0.000169468

2.2668 -0.034264 U Xl 3 ooJIO - 900

0.93147 -2.2512 uY3 150

x = 7.4663 -1.9315 U

X4 3 ooJIO - 900 -1.9315 4.9178 U

Y4 450

(1.82)

(1.83)

(1.84)

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Chu:cmg 2 T6ng quan vJ phdn mJm ANSYS

Chu'dng2 ,.""., '.I\. '.I\. '.I\.

TONG QUAN VE PHAN MEM

ANSYS

Hi~n nay, vi~c giai cac bai toan ca hoc la mot vi~c vo cung dn thi~t nhung vi~c giai chung thi r~t la kh6 khan, nh~t la vai nhung bai toan c6 mo hinh Ian va phuc t~p dn su d\lllg r~t nhi~u bi~n va cac di~u ki~n bien phuc t~p vai khong gian nhi~u chi~u thi vi~c giai b~ng tay la

mot vi~c r~t kh6 khan c6 khi khong th~ th\Ic hi~n duQ'c. ANSYS la mot ph~n m~m m~nh duQ'c phM tri~n va ap d\lllg rong rai tren toan th~ giai, b~ng cach su d\lllg phuang phap ph~n tu huu

h~n (FEM - finite element method) trong tinh toan, da dap ung duQ'c nhung yeu du n6i tren

cua cac bai toan ca hoc. Nhung uu di~m n6i bac cua ANSYS nhu sau:

• Giai duQ'c nhi~u bai toan nhu: phan tich k~t du (tuy~n tinh va phi tuy~n), truy~n nhi~t, ca hoc ch~t long, cac bai toan am hoc va tu truang ...

• Thu vi~n ph~n tu Ian.

• Xu ly k~t qua cao dp, cho phep ve dE> thi, tinh toan t6i uu ...

• C6 th~ su d\lllg nhu mot ngon ngu lap trinh.

• Kha nang dE> ho~ m~nh va c6 th~ lien k~t vai cac ph~n m~m CAD/CAM khac.

• Giam chi phi san xu~t vi c6 th~ tinh toan thu nghi~m, ...

I. KHm DQNG ANSYS.

Nhu cac ph~n m~m khac thi khai dong ANSYS b~ng cac cach sau:

.:. Tren thanh Taskbar chon: Start / Programs / ANSYS 9. 0 / ANSYS Product Launcher .

• :. Click dup chuot vao bi~u tUQ'ng "ANSYS Product Launcher" tren desktop (n~u c6)

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Sau d6 mim hinh se xu~t hi~n cua sf> "9.0 Launcher", k~ ti~p chon m\lC "File manegement". Trong cua sf> mai chon duang d~n cho file dn luu gifr (working directory) va d~t ten cho bai toan (job name). Sau khi chon xong chon "Run" thi chuang trinh ANSYS se duO'c khai dong.

II. GIAO Dl¢N ANSYS. Sau khi khai dong chuang trinh ANSYS thi man hinh se hi~n:

~ Preferences (±) Preprocessor

I±I Solution

I±I Run-Time Stat. ~ Session Editor ~ Finish

NODE S

I Pick a menu item or enter an ANSVS Command (BEGIN)

x

I mat~l I type~l

Hinh 2.1 Giao di~n ANSYS.

[A]: MENU Tl¢N leH (Utility Menu). a. File (quan ly dfr li~u).

b. Select (chon Iva). c. List (Ii~t ke). d. Plot (hi~n thi d~ng dE> ho~). e. PlotCtrls (Iva chon trnac khi Iva chon d~ng dE> ho~). f. WorkPlane (m~t ph~ng lam vi~c). g. Parameters (quan ly cac thong s6).

h. Macro (t~o cac d~ng chu~n). 1. MenuCtrls (chon Iva cach hi~n thi cac Menu). J. Help (trO' giup).

[B]: NH~P DU Ll¢U BANG L¥NH (Input).

J\N f-lAR .17 2:00 8

I csys~O I secn~l

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Su d\lllg cho huang giao ti~p b~ng l~nh.

[C]: THANH CONG CV (Toolbar). Thucmg xuyen su d\lllg cho huang giao ti~p b~ng chuot.

[D]: MENU CHINH (Main menu). Thucmg xuyen su d\lllg trong ANSYS cho huang giao ti~p b~ng chuot.

[E]: VUNG HIEN THJ (Graphics). Hi~n thi cac k~t qua b~ng dE> ho~.

Phong to thu nho d6i tUQ'ng tren Graphics: cling nhu cac ph~n m~m khac thi ANSYS

cling cung dp cac cang C\l d~ co th~ di chuy~n khung nhin thea y mu6n. Co th~ phong to thu

nho ho~c xoay khung nhin b~ng thanh cang C\l ben tay phai milll hinh ho~c co th~ th\Ic hi~n thea hop tho~i b~ng cach th\Ic hi~n thea duang d~n:

COMMAND: Utility Menu ~ PlotCtrls ~ Pan ZoomRotate . Xu~t hi~n hOp tho~i Pan-Zoom

Rotate nhu bi~u di~n a hinh 2.2.

----

Pan -Zoom -Rotate

Window I' ~

Rate

r Dynamic Mode

r. Model r Lights

Reset

Close Help

[A]: Cac huang nhin.

[B]: Cac ch~ do phong to thu nho.

[C]: Di chuy~n thea b6n phuong.

[D]: Xoay quanh cac tf\lC toa do.

[E]: Do Ian di chuy~n, xoay, phong to ho~c thu nho. DuQ'c tinh thea gia tri "%".

[F]: Hi~n thi rna hinh vua du vai man hinh.

Hinh 2.2

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III. LUU TRU vA HOI PHVC. COMMAND: Utility Menu~File~Save as~d~t tenfile, chon thu m\!c~OK (du li~u luu vai ph~n rna rong la *0 db )

ANSYS Multiphysics U Save DataBase

Eile ~elect ~ist ~Iot Plo Save Database to

Clear & Start New 0" I_ Change Jobname 0" r--------: Change Directory '" Change Title '"

Resume Jobname, db '" Resume from, "

Save as Jobname, db Save as , .

Directories:

c:\doeuments and settings\t

DC:\ "' I D Documents and SE-I f5t -LJ Cookies LJ Desktop ~ LJ Favorites ~J

List Files of Type: Drives:

OK

Cancel

Help

I Database Files (". db") :::oJ r-11EI- c- : -----3""" Network ...

Hinh 2.3

Mu6n rna l~i bai tmln da tinh: COMMAND: UtilityMenu~File~Resumefrom. Sau d6 chon file dn rna, sau d6 b~m OK.

- ------------

Resume Database

Resume D atabase From

1-file. db file.dbb

List Files of Type:

I Database Files (". db") ..::I

Directories:

c: \documents and settings\t

I27c\ "' I 127 DOCUMENTS ANI .~ f5T LJ Cookies

LJ Desktop

LJ Favorites v i

Drives:

l rae: 3

OK ]

Cancel I Help

Network ...

r Ignore parameters on .db file r Suppress auto plotting

Hinh 2.4

IV. eAu TRUe BAI ToAN TRONG ANSYS. Khi tinh tmln b~t ky mot bai tmln ANSYS nao thi cling qua cac cong do~n sau: 1. Tqo ma hinh tinh - Preprocessing: g6m cac buac:

(i) Dinh nghla di~m chinh/du(mg/di~n tich/th~ tich (keypoints/lines/areas/volumes),

(ii) Dinh nghla ki~u ph~n tu (element type) va tinh ch~t vat li~u/hinh hoc (material/geometric).

(iii) T~o luai du(yng/di~n tich/th~ tich (lines/areas/volumes). Muc do chi ti~t ph\! thuoc s6luQ'ng chi~u cua bai toan, vi d\! 1D, 2D, b~t d6i xung, 3D.

2. Tinh toan - Solution: d~t tai trong (h,rc di~m ho~c ap suk .. ), cac rang buoc (do dich chuy~n, g6c xoay) va tinh toano

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3. Xir If; Mt qua - Postprocessing: cac buac bE> sung va xem k~t qua. Trong ph~n nay co th~ bao g6m:

(i) (ii) (iii)

(iv)

Danh sach chuy~n vi nut.

Lvc va mamen cua cac ph~n tU. D6 thi chuy~n vi.

Bi~u d6 duang muc ung su~t ho~c nhi~t do ...

v. ViDV 1. Giai bai toan cho a vi d\l v~ giim da duQ'c cho a chuang 1 b~ng ANSYS. Xet mot M gian nhu hinh 2.5. T~t ca cac thanh d~u lam b~ng g6 vai madun dan h6i

E = 1.9 X 106 (N/m2) va di~n tich m~t c~t ngang la 8 m2. Tinh ung su~t, chuy~n vi trong m6i

ph~n tu thanh gian va phan Ivc t~i hai g6i.

SOON SOON

36m 36m

2

Hinh 2.5

ANSYS dua ra hai ki~u ph~n tu d~ phan tich bai toan v~ gian la: LINK1 va LINK8. d day d~ giai bai toan tren dung ph~n tu LINK1

Ph~n tu LINK1la ph~n tlr d6i xung tfl)C, co hai nut (i va}), co hai bac w do (Ux va Uy ). Nhu

bi~u hi~n hinh 2.6. Mu6n tim hi~u them co th~ vao "Help" cua ANSYS r6i nhap LINK1.

Y

I X

Hinh 2.6 Hinh d~ng ph~n tu LINK1.

J

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1. ChQn ki~u ph An tir. COMMAND: Main Menu ~ Preprocessor ~ Element Type ~ Add/ Edit/Delete.

• Cua sf> "Element Types" xu~t hi~n • Nh~p vao Add lam xu~t hi~n cua sf> "Library of Element Types" d~ chon cac ph~n tu

dn su d\mg.

• Nh~p chon Link r6i chon 2D spar 1, sau d6 chon Apply.

• Cua sf> "Element Types" xu~t hi~n d~ng ph~n tu thu nh~t la LINKl.

• B~m Close.

2. Nh~p di~n tich rn~t dt ngang cho tung phAn tir giim. COMMAND: MainMenu~Preprocessor~Real Constans~Add/ Edit/Delete.

• Cua sf> "Real Cons tans" xu~t hi~n • Nh~p vao Add lam xu~t hi~n cua sf> "Element Type for Real Constans", nh~p chon

ph~n tu LINK1 r6i b~m OK.

• Cua sf> "Real Constansfor LINK1" xu~t hi~n, nhap thong sf>: ./ AREA = 8

• B~m OK, thi cua sf> "Element Type for Real Cons tans" xu~t hi~n Set l.

• B~m Close.

3. Nh~p tinh ch~t v~t li~u. COMMAND: Main Menu ~ Preprocessor ~ Material Props ~ Material Models.

• Cua sf> "Define Material Model Behavior" se xu~t hi~n. • Nh~p doi vao Structural, Linear, Elastic, va Isotropic lam xu~t hi~n hop tho~i "Linear

Isotropic Properties forMate rials Number 1".

• Nhap vao cac gia tri EX = 1.ge6 va PRXY = O.

• T~t cac cua sf>

4. T~o rno hinh tinh toano a) Tq.o node.

COMMAND: MainMenu ~ Preprocessor ~ Modeling ~ Create ~ Nodes ~ In Active Cs.

• Cua sf> "Create Nodes in Active Coordinate System" xu~t hi~n.

• T~o cac node:

Node No. X Y

1 0 0

2 36 0

3 0 36

4 36 36 5 72 36

Bang 2.1

• B~m OK.

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b) Tqo element

COMMAND: MainMenu~Preprocessor~Modeling~Create ~ Elements~ Auto Numbered ~ Thru Nodes.

• Cua sf> "Element from Nodes" xu~t hi~n, d6ng thai mim hinh xu~t hi~n hinh mlii ten

huang len (t ). • T~o cac ph~n tu theo cac nut:

.,/ Element (1): nh~p node 1

va node 2 ~ Apply. .,/ Element (2): nh~p node 2





va node 5 ~OK.

5. Ap d~t di~u ki~n bien va tai tn.mg. a) fJiJu ki¢n bien vJ chuyJn vi.

J\N E-N

AUG 28 2008

3 6

Hinh 2.7

COMMAND: Main Menu ~Solution ~ Define Loads ~ Apply ~ Structural ~ Displacement

~OnNodes.

• Cua sf> "Apply U ROT on Nodes" xu~t hi~n, d6ng thai man

hinh cling xu~t hi~n hinh mlii ten

huang len (t ). • Nh~p chon node 1 va 3, r6i b~m

OK, cua sf> "Apply U ROT on Nodes" khac xu~t hi~n.

• Chon ALL DOF trong 6 Lab2 va nhap gia tri 0 vao 6 Displacement value

• Nh~p OK.

E-N

u

3

2

•• ' ·::.i!·.x;.:....-___ l ___ ---.:>V : ..... ~~ ... :

Hinh 2.8

6

AUG 28 2008 22 : 10 : 20

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b) Ll;fC tqp trung.

COMMAND: Main Menu ~ Solution ~ Define Loads ~ Apply ~ Structural ~ ForcelMoment

~OnNodes.

• Cua sf> "Apply FIM on Nodes" xu~t hi~n, d6ng thai mim hinh cling xu~t hi~n hinh mlii

ten huang len (t ). • Nh~p chon node 4 va 5 r6i b~m OK, thi cua sf> "Apply FIM on Nodes" khac xu~t hi~n. • Chon FY trong 6 Lab va nhap gia tri -500 vao 6 VALUE, r6i nh~p OK.

E -N

U .-

3 3 4 6

AUG 28 2008 22 : 11: 11

5 ~---------------•. -----------------.

2 4

a. x 1

Hinh 2.9

6. Giai bili to an. COMMAND: MainMenu ~ Solution ~ Solve ~ Current LS.

• Xu~t hi~n cua sf> "Solve Current Load Step" va "/STATUS Commands".

• Nh~p OK tren cua sf> "Solve Current Load Step"

• D~n khi nao hi~n len cua sf> "Note" la da k~t thuc qua trinh tinh toan

• Nh~p Close.

7. XU- If k~t qua. COMMAND: Main Menu ~ General Postproc ~ Plot Results ~ Deformed shape ~ chon m\lC

Def + undeformed

~ Plot Deformed Shape I X 1

[PLDISPj Plot Deformed Shape

KUND Items to be plotted

OK

r Def shape only

~r. peE+:~ndei~r0edJ r Def + undef edge

Apply I Cancel Help

Hinh 2.10

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a) ChuyJn vi thiing dzmg:

I\N COMMAND: Main Menu~General

Postproc ~ Plot Results ~ Contour

Plot~Nodal Solution.

NODAL SOLUTION

STEI'-l AUG 2B 2008

22:28 : 58

• Cua so "Contour Nodal

Solution Data" xu~t hi~n.

SUB -1 TIME-1 UY ( AVG)

RSYS-O DMX - . 019665 SMN --.019522

• Chon DOF Solution va Y-Component of displacement. D6ng thai chon Deformed

shape with undeformed edge trong 0 Undisplaced shape key.

R6i b~m OK, thi trnang chuy~n vi duqc cho a hinh 2.11 ben du6i

"MN

-/~ ..........

...• ,

. "., .. "'"

>- ..•.....

, ......

./ ,~r·

" /

- . 019522 - . 015184 - . 010846 -.006507 -.002169 - . 017353 - . 013015 -.008676 -.004338 0

Hinh 2.11

COMMAND: Utility Menu List~Results~Nodal Solution. Sau d6 chon tuang W nhu tren thi se c6 bang sf> li~u chuy~n vi cua tung nut.

~ PRNSOL Command ~ File

PRINT U NODAL SOLUTION PER NODE

***** POST1 NODAL DEGREE OF FREEDOM LISTING *****

LOAD STEP- 1 SUBSTEP- 1 TIME- 1.0000 LOAD CASE- 0

THE FOLLOWING DEGREE OF FREEDOM RESULTS ARE IN GLOBAL COORDINATES

NODE UX UY 1 0.0000 0 . 0000 2 -0.35526E-02-0.10252E-01 3 0.0000 0.0000 4 0.11842E-02-0.11436E-01 5 0.23684E-02-0.19522E-01

MAXIMUM ABSOLUTE UALUES

UZ 0 . 0000 0.0000 0.0000 0.0000 0.0000

NODE 2 5 0 UALUE -0.35526E-02-0.19522E-01 0.0000

Hinh 2.12

So sanh vai k~t qua tinh a chuang 1

{U2X : ~0.0035 m

U2Y

- 0.0102 m {U4X : ~.001l8 m

U4Y

- 0.0114 m

USUM 0 . 0000

0.10850E-01 0.0000

0. 1149?E-01 0.19665E-01

5 0.19665E-01

{USX : ~.00240 m

USY

- 0.0195 m

Ta th~y r~ng k~t qua giai b~ng ANSYS phil hqp vai k~t qua tinh b~ng phuang phap ph~n tu huu h~n.

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Chucmg 2 T6ng quan vJ phdn mJm ANSYS

b)Phan b;rc

COMMAND: Utility Menu List ~ Results

~ Reaction solution

K~t qua phan h,rc giai b~ng ANSYS cling

phil hqp vai k~t qua tinh b~ng phuang

phap ph~n tu huu h~n.

c) Truemg zmg sudt va n(Ji b;rc

~ .

r!1 PRRSOL Commdnd ~ File

PRINT REACTION SOLUTIONS PER NODE

***** POST1 TOTAL REACTION SOLUTION LISTING *****

LOAD STEP= 1 SUBSTEP= 1 TIME= 1.0000 LOAD CASE= 0

THE FOLLOWING X,Y,Z SOLUTIONS ARE IN GLOBAL COORDINATES

NODE FX 1 1500.0 3 -1500.0

TOTAL UALUES UALUE 0.0000

FY 0.0000 1000.0

1000.0

Hinh 2.13

Vilo "Help" d~ xem d~u fa cua ph~n tu LINKI

I Name I Definition 0 R

III IElement Nwnber Y Y

IN ODES IElement node nwnbers (I and J) Y Y

IMAT IMaterial nwnber for the element Y Y

IVOW IElement volume . Y

Ixc, YC ILocation where results are reported Y f ITEMP ITemperature at nodes I and J Y Y

IFWEN IFluence at nodes I and J Y Y

IMFORX~ IMember force in the element coordinate system X direction Y Y

ISAXL~ IAxial stress in the element Y Y

IEPELAXL - IAxial elastic strain in the element Y Y

IEPTHAXL IAxial thermal strain in the element Y I Y

IEPINAXL IAxial initial strain in the element Y Y

ISEPL IEquivalent stress from the stress· strain cwve 1 1 ISRAT IRatio of trial stress to the stress on yield swface 1 1 IEPEQ IEquivalent plastic strain 1 1 IHPRES IH ydrostatic pressure 1 1 IEPPLAXL IAxial plastic strain 1 1 IEPCRAXL IAxial creep strain 1 1 IEPSWAXL IAxial swelling strain 1 1

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Ou"iput Quantity Name I £fABLE and ESOL Command Input

I Item I E I I I J

I~LS -SA XL I (.1) I - I -EPELAXL I LEPEL I 1 I - I -EPTHAXL LEPTH I 1 I I -EPSWAXL LEPTH I 2 I - I -EPINAXL LEPTH I 3 I - I -

EPPLAXL LEPPL I 1 I - I -EPCRAXL LEPCR I 1 I - I -

SEPL NUN I 1 I - I -SRAT NUN I 2 I - I -HPRES NUN I 3 I I -EPEQ NUN I 4 I - I -

MFORX I~SMISC I (. 1) I - I -

FLUEN I NMISC I - I 1 I 2

TEMP I LBFE I - I 1 I 2

Hinh 2.14

L~y noi h,1c: COMMAND: MainMenu~ General Postproc~Element Table~Define Table.

• Xu~t hi~n cua sf> "Element Table Data".

• Nh~p vao Add lam xu~t hi~n cua sf> "Define Additional Element Table Items"

• Nhap "AXFORCE' vao 6 Lab.

• Trong ph~n Item,Comp keo thanh cuon xu6ng d~ chon m\lC By sequence num.

• Trong 6 k~ ben chon SMISC.

• Trong 6 a du6i them s6 1 vao nhu sau: "SMISC, 1", r6i b~m OK.

L~y ung su~t: COMMAND: MainMenu ~ General

Postproc ~ Element Table ~ Define Table.

• Xu~t hi~n cua sf> "Element Table Data".

•

•

Nh~p vao Add lam xu~t hi~n cua sf> "Define Additional Element Table Items".

Nhap "AXSTRESS" vao 6 Lab.

• Trong ph~n Item,Comp keo thanh cuon xu6ng d~ chon m\lC By sequence num.

• Trong 6 k~ ben chon LS.

• R6i trong 6 a du6i ta them s6 1 vao nhu sau: "LS, 1", r6i b~m OK.

~ PRETAB Command ~ File

PRINT ELEMENT TABLE ITEMS PER ELEMENT

***** POST1 ELEMENT TABLE LISTING *****

SIAT ELEM

1 2 3

Ii

CURRENT AXFORCE

-1500.0 1414.2 500.00

=~I! : ~~ MINIMUM UALUES ELEM 1 UALUE -1500.0

MAXIMUM UALUES ELEM 2 UALUE 1414.2

CURRENT AXSIRESS

-187.50 176.78 62.500

=UJII I 1

-187.50

2 176.78

Hinh 2.15

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Xem k~t qua:

COMMAND: MainMenu~ General Postproc~List Results~Elem Table Data.

• Cua s6 "List Element Table Data" xu~t hi~n.

• Chon AXFORCE va AXSTRESS trong 6 Lab 1-9

• R6i b~m OK. Thi xu~t hi~n bang PRETAB nhu hinh 2.15.

So sanh vai k~t qua noi h,rc va ung su~t tren ph~n tu thu (5) 0 chuang 1 l~n luQ'c la 696 N va

87 N/m 2 . K~t qua kha phil hQ'p.

VI. viDV2 Giai bai toan ung su~t ph~ng duQ'c cho 0 vi d\l 2 cua chuang 1. Su d\lng ph~n tu tam giac tuy~n tinh va tu giac tuy~n tinh d~ xac dinh chuy~n vi cua cac nut va

ung su~t trong cac ph~n tu cua mot t~m mong duQ'c rang buoc chuy~n vi va chiu tac d\lng cua cac h,rc b~ m~t nhu hinh 2.16. Ngoai ra t~m mong con d~t trong m6i trnang nhi~t do thay d6i tu I1T = IODC d~n nhi~t do chu~n. T~m mong co b~ day 0.5cm, m6dun dan h6i Young E =

15x 106 N/cm2 , M sf> Possion v = 0.25, M sf> gian no nhi~t ex = 6x 10-6

.

A. nUNGPHANTUTAMGIAC 1. Nh~p tiuh ch~t v~t li~u:

600N/cm2

Hinh 2.16

COMMAND: Main Menu ~ Preprocessor ~ Material Props ~ Material Models.

• Cua s6 "Define Material Model Behavior" se xu~t hi~n.

• Nh~p d6i vao Structural, Linear, Elastic va Isotropic lam xu~t hi~n hop tho~i "Linear

Isotropic Properties forMate rials Number 1".

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• Nhap vito cac gia tri EX= lSe6 vaPRXY= O.2S.

• Tren cua s6 "Define Material Model Behavior".

• Nh~p d6i vao Structural, Thermal Expansion, Secant Coefficient va Isotropic lam xu~t hi~n hop tho~i "Linear Isotropic PropertiesforMaterials Number 1".

• Nhap vao cac gia tri APLX = 6e-6, r6i b~m OK.

• T~t cac cua s6.

2. ChQn ki~u ph An tir

COMMAND: Main Menu ~ Preprocessor ~ Element Type ~ Add/ Edit/Delete.

• Cua s6 "Element Types" xu~t hi~n. • Nh~p vao Add lam xu~t hi~n cua s6 "Library of Element Types" d~ chon cac ph~n tu

dn su d\mg.

• Nh~p chon ph~n tu Structural Mass - Solid

• Chon ki~u ph~n tu Quad 4node 42 r6i b~m OK

• Cua s6 "Element Types" xu~t hi~n d~ng ph~n tu PLANE42.

• Nh~p chon m\lC Option d~ lam xu~t hi~n cua s6 "PLANE42 element type options".

• Chon di~u ki~n Plane strs w/thk trong hOp thoai "Element behavior" d~ dinh tr~ng thai cho ph~n tu.

• B~m OK r6i b~m Close.

3. ChQn chi~u day phAn tir.

COMMAND: Main Menu ~ Preprocessor ~ Real Constants ~ Add/Edit/Delete.

• Cua s6 "Real Constants" xu~t hi~n. • Nh~p vap Add lam xu~t hi~n cua s6 "Element Type for ReaIConstants".

• Nh~p chon OK d~ lam xu~t hi~n cua s6 "Real Constants Set Number 1 for PLANE42".

• Nhap gia tri O.S vao 6 Thickness r6i nh~p OK.

• Cua s6 "Real Constants" xu~t hi~n tr6' l~i va xu~t hi~n Set l.

• Nh~p Close.

4. T~o rno hinh tinh toan:

a) T~o node. COMMAND: MainMenu ~ Preprocessor ~ Modeling~ Create ~ Nodes ~ In Active Cs.

• Cua s6 "Create Nodes in Active Coordinate System" xu~t hi~n.

• T~o cac Node co toa do nhu sau: NodeN(J X Y

1 0 0

2 2 0

3 2 3

4 1 3

Bang 2.2

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• R6i b~m OK b) T~o ph~n tu

COMMAND: MainMenu~Preprocessor~Modeling~Create ~ Elements~ Auto

Numbered ~ Thru Nodes.


huang len (t ). • Ta nh~p l~n luot cac Node 1, 2 va 4 r6i b~m Apliy, thi duQ'c ph~n tu (1).

• Cua sf> "Element from Nodes" xu~t hi~n tr6' l~i, d6ng thai man hinh xu~t hi~n hinh mlii

ten huang len (t ). • Ta nh~p l~n IUQ't cac nut 2, 3 va 4 r6i b~m OK, thi duQ'c ph~n tu (2).

c) Xem rna hinh ph~n tU.

COMMAND: UtilityMenu~Plot Ctrls~ Numbering.

• Cua sf> "Plot Numbering Controls" se xu~t hi~n.

,.-------------------------------YU-,

• Nh~p chon a Node numbers (NODE) tu offsang on

• Chon m\lc Element

numbers trong a ElemlAttrib numbering r6i

b~m OK.

COMMAND: Utility Menu~Plot~

Multi-Plot. Sau d6 rna hinh ph~n tu

duQ'c t~o nhu hinh 2.17.

5. Nh~p di~u ki~n bien. a) Nhap di~u ki~n rang buoc 6' d~u ben trai:

E-N 4 3

Hinh 2.17

AUG 28 2008 22 : 48 : 22

COMMAND: Main Menu ~ Solution ~ Define Loads ~ Apply ~ Structural ~ Displacement

~OnNodes.

• Cua sf> "Apply U ROT on Nodes" xu~t hi~n, d6ng thai man hinh cling xu~t hi~n hinh

mlii ten huang len (t ). • Nh~p chuot chon Node 1 va 2 r6i b~m OK thi cua sf> "Apply U ROT on Nodes" khac

xu~t hi~n. • Chon UY trong a Lab2 va nhap gia tri 0 vao a VALUE nh~p Apply.

• Cua sf> "Apply U ROT on Nodes" xu~t hi~n tr6' l~i, d6ng thai man hinh cling xu~t hi~n

hinh mlii ten huang len (t ). • Nh~p chuot chon Node 2 va 3 r6i b~m OK thi cua sf> "Apply U ROT on Nodes" khac

xu~t hi~n.

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• Chon UX trong 0 Lab2 va nhap gia tri 0 vao 0 VALUE, r6i nh~p OK.

b) Nhap h,rc tac d\lllg COMMAND: Main Menu ~ Solution ~ Define Loads ~ Apply ~Structural ~ ForcelMoment

~OnNodes.

• Cua sf> "Apply FIM on Nodes" xu~t hi~n, d6ng thai man hinh cling xu~t hi~n hinh mlii

ten huang len (t ). • Nh~p chuot chon Node 1 va 4 r6i b~m OK thi cua sf> "Apply FIM on Nodes" khac xu~t

hi~n.

• Chon UX trong 0 Lab va nhap gia tri 300* sqrt(1 0) vao 0 VALUE, r6i nh~p Apply.

• Cua sf> "Apply FIM on Nodes" xu~t hi~n tr6' l~i, d6ng thai man hinh cling xu~t hi~n

hinh mlii ten huang len (t ). • Nh~p chuot chon Node 3 va 4 r6i b~m OK thi cua sf> "Apply FIM on Nodes" khac xu~t

hi~n .

• Chon UY trong 0 Lab va nhap gia tri -150 vao 0 VALUE, r6i nh~p OK.

c) Nhap di~u ki~n nhi~t do COMMAND: Main Menu ~Solution ~ Define Loads ~ Apply ~ Structural ~ Temperature

~ Uniform Temp

• Cua sf> "Uniform Temperature" xu~t hi~n.

• Nhap gia tri 10 vao 0 Uniform Temperature, r6i b~m OK.

6. Giai bili toaD (solution) COMMAND: MainMenu ~ Solution ~ Solve ~ Current LS.

• Xu~t hi~n cua sf> "Solve Current Load Step" va "/STATUS Commands", nh~p OK.

• D~n khi nao hi~n len cua sf> "Note" la da k~t thuc qua trinh tinh toan

• Nh~p Close.

7. XU- If k~t qua a) Xem hinh bi~n d~ng cua t~m mong

COMMAND: Main Menu ~ General

Postproc ~ Plot Results ~ Deformed Shape

• Cua so "Plot Deformed Shape" xu~t hi~n.

• Chon m\lC Def + undef edged, r6i b~m OK. Thi t~m bi~n d~ng nhu hinh 2.18

DI SPLACEMENT

ST EP=l SUB ~1 TIME~l

4 3

Hinh 2.18

AN AUG 28 2008

23 : 0B : 07

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COMMAND: Utility Menu ~ List ~ Results ~ Nodal Solution

• Cua sf> "List Nodal Solution" xu~t hi~n. • Chon Nodal Solution ~ DOF Solution ~ Displacement vector sum.

• R6i b~m OK. Thi bang PRNSOL xu~t hi~n nhu hinh 2.19.

-------






NODE UX UY 1 0.35784E-04 0.0000 2 0.0000 0.0000 3 0.0000 0. 15700E-03 4 0.17198E-04 0.16637E-03

UZ 0.0000 0.0000 0.0000 0.0000

Hinh 2.19

Ta co k~t qua tinh b~ng FEM trong chuang 1 Iii.:

u Xl 0.0000357839 0.357839x10-4

u Y3 0.000157003 0.157003 x 10-3

= cm u 0.0000171983 0.171983 x 10-4

x4

u Y4

0.000166367 0.166367 x 10-3

USUM 0.35784E-04

0.0000 0 . 15700E-03 0 . 16725E-03

So sanh hai k~t qua thi ta th~y Iii. hai k~t qua Iii. trimg hqp nhau.

B. nUNGPHANTUTUGIAC 1. Nh~p tinh ch~t v~t li~u: (tuang W ph~n A)

2. ChQn ki~u ph An tir: (tuang W ph~n A)

3. ChQn chi~u day phAn tir: (tuang W ph~n A)

4. T~o rno hinh tinh toan:

a) T~o node.

~I

~ I

COMMAND: MainMenu ~ Preprocessor ~ Modeling~ Create ~ Nodes ~ In Active Cs.

• Cua sf> "Create Nodes in Active Coordinate System" xu~t hi~n. • T~o cac key point co toa do nhu sau:

NodeN(J X Y

1 0 0

2 2 0

3 2 3

4 1 3

Bang 2.3

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• R6i b~m OK

b) T~o ph~n tu COMMAND: MainMenu~Preprocessor~Modeling~Create ~ Elements~ Auto

Numbered ~ Thru Nodes.


huang len (t ). • Ta nh~p l~n luot cac Node 1,2, 3 vii. 4 r6i b~m OK.

5. Nh~p di~u ki~n bien: (tuang W ph~n A)

6. Giai bili to an (solution) (tuang W ph~n A)

7. XU- If k~t qua: (tuang W ph~n A) Ta co k~t qua sau:






NODE UX UY 1 0.29595E-04 0.0000 2 0.0000 0.0000 3 0 . 0000 0. 14441E-03 4 0.2338?E-04 0.1?266E-03

UZ 0.0000 0.0000 0 . 0000 0.0000

USUM 0.29595E-04

0.0000 0. 14441E-03 0.1?424E-03

Hinh 2.20

Ta co k~t qua tinh b~ng FEM trong chuang 1 Iii.:

u Xl 0.0000307806 0.307806x10-4

u Y3 0.000150801 0.150801x10-3

= cm u 0.0000222016 0.222016x10-4

X4

u Y4

0.000169468 0.169468 x10-3

So sanh hai k~t qua thi th~y Iii. hai k~t qua Iii. kha trung hqp nhau.

~I

v i

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Chu:cmg 3 Tqo ma hinh tinh toan trong ANSYS

Chu'dng3 A' , ,

TAO MO HINH TINH TOAN TRONG .

ANSYS

I. T~O MO HINH TRVC TIEP TRONG ANSYS. T~o mo hinh tinh tmln trong ANSYS la mot cong vi~c kh6 khan va kha t6n thai gian, vi yay d~ lam quen vai cach t~o mo hinh trong ANSYS thi chuang nay se giai thi~u sa luQ'c v~ cach t~o mo hinh thong qua mot vai vi d\l tu d~ d~n kh6 d~ doc gia c6 th~ thvc hi~n thu~n ph\lc. Trong ANSYS thi mo hinh c6 th~ la d~ng duang, m~t ho~c kh6i; vi yay trinh W trinh bay 6 day cling di thea nhu th~.

1) H~ tr\lc tQa dQ va m~t ph~ng lam vi~c Trnac khi t~o mo hinh thi di~u d~u tien la chung ta dn bi~t la chung ta dang lam tren toa do

gi? (Descartes, cvc hay tf\l). Trong ANSYS m~t dinh la h~ toa do Descartes vuong g6c OXYZ (M toa do tuy~t d6i), d6ng thai m~t ph~ng lam vi~c (M toa do tuang d6i) la m~t ph~ng trung

vai m~t ph~ng OXY cua M toa do tuy~t d6i. Khi kh6i dong man hinh ANSYS thi luc b~y gia M tf\lC toa do hi~n thi tren mam hinh la M tf\lC toa do tuy~t d6i, m~t ph~ng lam vi~c trung vai m~t ph~ng OXY cua M toa do nay va trung vai man hinh. Mu6n hi~n thi m~t ph~ng lam vi~c thi: Utility Menu~ WorkPlane~Display Working Plane. Luc d6 gird (luai di~m) se xu~t hi~n tren m~t ph~ng lam vi~c. Mu6n nhin thea

ch~ do 3D (nhu hinh 3.1) thi b~m vao bi~u tUQ'ng Isomatric View c:o I tren thanh cong C\l ben phai man hinh.

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NODES

MAT NUM

Hinh 3.1

Mu6n ehinh sua Gird:

AN MAR 17 2008

22 , 55 , 05

E.ile 2elect list !:Iot PlotQrls (0.:?'~:~~~~~) Pa[ameters [1acro MeQuCtris tielp

Display Working Plane

Show WP Status

WP Settings '"

Offset WP by Increments

Offset WP to

Align WP with

Change Active CS to

Change Display CS to

Local Coordinate Systems

~

~

~

~

~

WP Settin&s

(0 Cartesian

r Polar

r Grid and Triad

(0 Grid Only

r TriadOnly

P" Enable Snap

Snap Incr 10.1 l SnapAng 15 J

Spacing 105

Minimum 1.1 1 Maximum 11 J Tolerance 10.003

I OK I Apply

Reset I Cancel

Help I

Hinh 3.2

I I

Ch on ki~u toa do.

An lHi~n grid va m~t ph~ng lam vi~e.

DO Ian cae 6 truy b~t di~m

Khoang each gifra cae duang grid.

Giai h~n eua grid.

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a) Di chuyJn mqt phiing lam vi¢c

B~ng hop tho~i:

Eile 2elect !,.ist ~Iot


Show WP Status

WP Settings '"

offset INP by Increments ' "

Offset WP to

Align WP with

Change Active CS to



~

~

~

~

~

xoay quanh M tll)e m~t ~ { ph~ng lam vi~e thea eae--.J phuang X, Y ho~e Z eua h~

toa do tuy~t d6i.

Offset WP

[EJ w:J ~ [ill CEJ ~

1

~ ~ Snaps K Y. Z Offsets

I

LEru I~+xl Ir-~I I~+YI I z-~I I ~ +z-I

30

~ ~ ~ Degrees

Xi. YZ. ZX Angles

I Global X= 0

Y= 0

Z= 0

r Dynamic Mode ,

~ ~ ~ Cancel I ~

Meo.uctrls tielp

}+-h-

L

lIE

lIE

di ehuy~n tinh ti~n thea mot khoang dll m~t dinh

do Ian khoang dieh ehuy~n tinh ti~n.

di ehuy~n tinh ti~n b~ng each nhap toa do.

do Ian khoang xoay (tinh thea do).

xoay b~ng each nhap thong s6.

di ehuy~n ho~e xoay W dong b~ng ehuOt.

Hinh 3.3 HOp tho~i Offset Wp,

B~ng menu sf> ra:

Eile 2elect !,.ist ~Iot PlotCtrls (W~';kP'I~~~") Par.ameters !1acro - . ..-;;:::, ............... . Meo.uCtrls tielp


Show WP Status

WP Settings '"


Offset V'I'P to ~ Keypoints + lIE @® Align WP with

Change Active CS to



Nodes + "'IIE~---------· XYZ Locations + "'IIE~--------©C

~ ----------------~ Global Origin ... IIE~-----------@ ~ Origin of Active CS lIE ®

Hinh 3.4

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@ +-- di chuy~n m~t ph~ng lam vi~c t6'i m~t ph~ng t~o boi cac keypoint (co th~ la mot keypoint).

® +-- di chuy~n m~t ph~ng lam vi~c t6'i m~t ph~ng t~o boi cac node (co th~ la mot

nodes).

© di chuy~n m~t ph~ng lam vi~c t6'i mot s6 di~m dinh trn6'c trong m~t ph~ng kich

C +--ho~t.

@ di chuy~n m~t ph~ng lam vi~c t6'i m~t ph~ng cua toa do tuy~t d6i (g6c m~t

+-- ph~ng lam vi~c trimg v6'i g6c toa do tuy~t d6i).

® di chuy~n m~t ph~ng lam vi~c t6'i m~t ph~ng dang kich ho~t (g6c m~t ph~ng

+-- lam vi~c trimg v6'i g6c m~t ph~ng dang kich ho~t).

b) Tqo mqt phiing lam vi¢c

Eile Select List Plot PlotCtrls (w~;j;pi~~~') Par.ameters Macro Meo.uCtrls t!elp - - - - .. -:::: ............... . Display Working Plane

Show WP Status

WP Settings '" Keypoints + ( @®

Offset WP by Increments ,,' Nodes + <111:(----------1-

Offset WP to ~ XYZ Locations + <III:(-------~© Align WP with ~ _______________________ P_la_n_e_N_o_rm_a_lt_o_Li_ne __ + __ ( @

Active Coord Sys ( ® Specified Coord Sys '" ( ® Global Cartesian <III:(~----------®

Change Active CS to ~

Change Display CS to ~

Local Coordinate Systems ~

Hinh 3.5

r:\ t~o m~t ph~ng lam vi~c qua ba keypoint (g6c m~t ph~ng lam vi~c trimg v6'i \01 +-- keypoint nh~p d~u tien).

t~o m~t ph~ng lam vi~c qua ba node (g6c m~t ph~ng lam vi~c trimg v6'i node

® +-- nh~p d~u tien).

© +-- t~o m~t ph~ng lam vi~c qua cac di~m dinh trn6'c trong m~t ph~ng kich ho~t.

t~o m~t ph~ng lam vi~c vuong goc v6'i mot duong. Khi th\Ic hi~n l~nh nay yeu

@ +-- du nhap RATIO LINE, chon trong khoang tu 0.0 d~n 1.0, do quy chi~u dai

do~n th~ng thanh 1 dan vi.

® +-- t~o m~t ph~ng lam vi~c trimg v6'i M toa do tuy~t d6i.

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® ~ t~o vi tri m~t ph~ng lam vi~c dva tu cac M tll)C toa do d~t bi~t. 0: M toa do vuong goc.

1: M toa do cvc.

2: M toa do duo

3: M toa do xuy~n. Khi co cac M tll)C toa do mai thi chung do ANSYS d~t va tu 11 tr6' di.

® ~ t~o m~t ph~ng lam vi~c trung vai m~t ph~ng dang kich ho~t.

c) Kich hoqt h¢ t9a d9 Eile 2elect !,.ist e.lot


Show WP Status

PlotCtrls (w~~'kPi~~·e) Par.ameters !:1acro - .. ;;;: ............... . Meo.uCtris !:!elp

WP Settings '"

Global Cartesian I( @ Global Cylindrical <llfiE-------.... @ Global Cylindrical Y E ©C Global Spherical .... E~-----------I@

Offset WP by Increments '"

Offset WP to ~

Align WP with ~

Specified Coord Sys '" .... E~-----------1®® Working Plane E .

Change Display CS to ~


Hinh 3.6

@ ~ chon M toa do vuong goc.

@ ~ chon M toa do cvc xoay thea phuang Z.

© ~ chon M toa do cvc xoay thea phuangy.

@ ~ chon M toa do duo

® ~ tu mot M toa do d~t bi~t. 0: M toa do vuong goc.

1: M toa do cvc vai z la tll)C xoay.

2: M toa do duo 3: khong co.

4 : m~t ph~ng lam vi~c. 5: M toa do cvc vai y la tll)C xoay.

11 tr6' di la b~t ky M toa do dia phuang duQ'c t~o.

® ~ tu m~t ph~ng lam vi~c.

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d) Tqo h¢ t9a d9 dia phu:cmg.

Eile ;ielect !,.ist ~Iot Plot~trls (#.:~~~~~~~.~) Par.ameters !1acro Meo.uCtrls tielp


Show WP Status

WP Settings '"


Offset WP to

Align WP with

Change Active CS to



Create Local CS ~

Delete Local CS '"

Move Singularity '"

At WP Origin ' " i( @ ® By 3 Keypoints + ",i(~-----. By 3 Nodes + "'i(~-------©C At Specified Loc + i( @

Hinh 3.7

@ +-- t~o M toa do dia phuang t~i g6e eua m~t ph~ng lam vi~e.

® +-- t~o M toa do dia phuang qua ba keypoint (g6e m~t ph~ng lam vi~e trung vai keypoint nh~p d~u tien).

© t~o M toa do dia phuang qua ba node (g6e m~t ph~ng lam vi~e trung vai node

C +-- nh~p d~u tien).

@ +-- t~o M toa do dia phuang b~ng m~t ehu~n dinh huang.

d) X6a h¢ t9a d9 dia phu:cmg.

Theo duang d~n:

Eile ;ielect !,.ist ~Iot Plot~trls ~orkPlane Pa!:ameters !1acro Meo.uCtrls tielp


Show WP Status

WP Settings '"


Offset WP to ~

Align WP with ~

Change Active CS to



Create Local CS

Delete Local CS '" "'i(~--X6a M toa do dia phuang. Move Singularity '"

Hinh 3.8

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2) T~o di~m (create keypoints)

ANSVS Main Menu

~ Preferences 8 Preprocessor

I±I Element Type I±I Real Constants I±I Material Props I±I 5ections 8 Modeling

t~o key point tu m~t ph~ng lam vi~c.

t~o key point b~ng cach nhap toa do.

t~o key point b~ng cach phM sinh tren mot line co trnac b~ng cach nh~p chuot tllJc ti~p.

8 Create , tao 0 ke11point ba.ng cach phM sinh tren mo. t line co 8 424'Hl!!lfl .)", , , ,

~ On wo.rking Plan2f trnac bang cach cho M so Line R~tio. H~ so nay bI In Active C5 duqc giai h~n trong khoang tu 0.0 denn 1.0. ,:0l On line +---~ On line w!Ratio

~ On Node I( t~o key points t~i mot vi tri nut co trnac. ,:0l KP between KPS~ .7l Fill between KPs t~o keypoint gifra hai key point co trnac: I±I KP at center , I±I Hard PT on line • Chon Ratio: de dinh khoang cach tlr keypoint I±I Hard PT on area thu nh~t d~n keypoint dn t~o thea M sf>

Hinh 3.9

3) T~o dlfirng (create lines) a) Du:emg thiing (lines) ANSVS Main Menu

~ Preferences 8 Preprocessor

I±I Element Type I±I Real Constants I±I Material Props I±I 5ections 8 Modeling

8 Create I±I Keypoints 8 lines 8_

.?l 5traight line ~ In Active Coord

khoang cach gifra hai keypoint ban d~u.

• Chon Dist: d~ dinh khoang cach tu keypoint thu nh~t d~n key point dn t~o.

t~o nhi~u keypoint l~p d~y gifra hai keypoint co trnac vai.

t~o line tu M toa do toan C\lC, khong quan Him d~n toa do hi~n hanh, va nh~p vao hai keypoint.

t~o line tu hai keypoint.

phM sinh line gifra hai key point tren mot m~t ph~ng.

t~o line vuong goc vai mot line cho trnac va di qua mot key point cho trnac.

t~o line vuong goc vai hai line cho trnac.

~ Overlaid on Area ..... ----J

.Jl Tangent to line t~o line di qua mot keypoint cho trnac va ~ Tan to 2 lines hqp vai mot line cho trnac mot goc xac ,:0l Normal to line : I I dinh. ,:0l Norm to 2 lines;<IIII-:---------'· I .Jl At angle to line ..... -------'

~ Angle to 2 lines.I(------- t~o line hqp vai hai line nhfrng goc xac dinh.

Hinh 3.10

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b) Cung tron (arcs)

ANSYS Main Menu

bI PreFerences EI Preprocessor

I±I Element Type I±I Real Constants I±I Material Props I±I Sections EI Modeling

EI Create I±I Keypoints EI lines

I±I lines

El m! ?I Through 3 KPs

?I By End KPs &: Rad ?l By Cent &: Radius +-_---J

t~o cung tron qua ba key point. Khoang khuy~t cua cung

tron 1a khoang gifra hai key point nh~p d~u tien.

t~o cung tron qua hai key point, d6ng thai xac dinh Him

va ban kinh cung tron.

t~o cung tron b~ng cach xac dinh Him, ban kinh va

di~m b~t d~u cua cung tron.

• ARC: goc t~o thanh cung tron.

• NSEG: s61uqng cung tron dn t~o.

?I full Cirde ... (~-----t~o CaC cung trcm l~p d~y mot vong tron.

Hinh 3.11

c) Du:emg spline ANSYS Main Menu

~ PreFerences EI Preprocessor

I±I Element Type I±I Real Constants I±I Material Props I±I Sections EI Modeling

EI Create I±I Keypoints EI lines

I±I lines I±I Arcs

EI mI!!! ?I Spline thru locs ?I Spline thru KPs

t~o duang spline co hai d~u mut 1a hai keypoint co

trnac. Sau do hinh d~ng co duqc b~ng cach nh~p tllJc

ti~p tren man hinh thong qua 1uai di~m

t~o duang spline di qua tap hqp cac key point.

t~o cac phan do~n spline di qua tap hqp cac

key point. Hai keypoint t~o thanh mot phan do~n.

~ Segmented Spline +-_---J I±I With Options

Hinh 3.12

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d) Bo cung gifra hai line

ANSYS Main Menu

~ PreFerences

EI Preprocessor

I±I Element Type

I±I Real Constants

I±I Material Props

I±I Sections

EI Modeling

EI Create

I±I Keypoints

EI lines

I±I lines

I±I Arcs

I±I Splines

Yl '@j@l®

Hinh 3.13

e) X6a line

Chi xoa line:

Ban kinh bo

[lFIll TJ Create Fillet line

NlI,Nl2 Intersecting lines

RAD Fillet radius

PCENT Number to assign·

. to generated keypoint at fillet center

OK Apply

17 15 '---_ .. r-I ---

r----. r-I ---

Cancel Help

Gan s6 thu w cho cung trcm duQ'c t~o ra

COMMAND: Main menu ~ Preprocessor ~ Modeling ~ Delete ~ Lines Only.

Xoa ca key point tren line:

COMMAND: Main menu ~ Preprocessor ~ Modeling ~ Delete ~ Line and Below.

4) T~o m~t ph~ng (create areas) a) Tqo tily y (Arbitrary)

ANSYS Main Menu

~ PreFerences

EI Preprocessor

I±I Element Type

I±I Real Constants

I±I Material Props

I±I Sections

EI Modeling

EI Create

I±I Keypoints

I±I lines

t~o area b~ng cach n6i cac keypoint l~i vai nhau.

t~o area ch6ng len mot area co trnac.

t~o area duQ'c giai h~n bai cac duang line.

-it dung

EI Areas

EI "rm"m~;·t·.i#·J }'l Through KPs

?l Overlaid on Area ~ By lines +-____ ....J

t~o area b~ng cach offset tu mot m~t ph~ng co - trnac. Phuang offset thea phuang phap tuy~n

cua m~t ph~ng ban d~u.

Jll By Skinning +-------' }'l By OrFset+-------.....J

Hinh 3.14

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b) M(tt phiing hinh chfr nhqt (Rectangle area)

ANSVS Main Menu

~ Preferences El Preprocessor

I±l Element Type I±l Real Constants I±l Material Props I±l Sections El Modeling

El Create I±l Keypoints I±l lines El Areas

I±l Arbitrary

El mbt.@ }11 By 2 Corners

~ By Centr & Cornr

t~o rectangle area b~ng cach nhap toa do 2 g6c cheo nhau

cua mot rectangle area.

t~o rectangle area b~ng cach nhap toa do Him va mot g6c cua mot rectangle area.

t~o rectangle area b~ng cach nhap toa do cua do dai

rectangle area thea phuang x va y so v6i M toa do

~ By Dimensions +-__ ---J

Hinh 3.15

c) M(tt phiing hinh trem (circular area)

ANSVS Main Menu


I±l Element Type I±l Real Constants I±l Material Props I±l Sections El Modeling

El Create I±l Keypoints I±l lines El Areas

I±l Arbitrary I±l Rectangle

t~o circular area b~ng cach dinh Him va ban kinh.

t~o circular area d~ng hinh xuy~n b~ng cach dinh Him va

hai ban kinh.

t~o mot ph~n circular area d~ng hinh xuy~n b~ng cach

dinh Him, hai ban kinh va hai g6c gi6i h~n.

El :m:m t~o mot ph~n circular area b~ng cach nh~p hai d~u }1 Solid Circle 2f mot duang kinh }1 Annulus .

}1 Partial Annulus

}1 By End Points t~o mot ph~n circular area b~ng cach nhap hai ban Id By Dimensions ... (~----

kinh va hai g6c gi6i h~n so v6i g6c toa do Hinh 3.16

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d) M(tt phiing da giac (polygon area)

ANSYS Main Menu

~ Prererences EI Preprocessor

I±I Element Type I±I Real Constants I±I Material Props I±I Sections

t~o m~t ph~ng hinh tam giac b~ng cach nhap trong Him va ban kinh duang trcm ngo~i ti~p tam giac do, ngoai ra con

nhap gia tri goc gifra tll)C x cua m~t ph~ng lam vi~c va tll)C nf>i tu Him d~n dinh d~u tien cua tam giac.

EI Modeling EI Create

I±I Keypoints I±I lines

tuang W nhu tren nhung m~t ph~ng t~o a day la hinh

chfr nhat.

EI Areas I±I Arbitrary I±I Rectangle I±I Circle

EI Jl!ltl!t!DJ }lI Triangle +----'

hinh ngfi giac.

hinh h,lc giac.

.7l Square +-------1 irhinh th~t giac. }lI Pentagon ~ }lI HeHagon -of"-------' I I hinh bat giac. }lI Septagon -ofd~-----.....J.

Jl Octagon -of1lE~--------' ~ By Inscribed Rad lIE @ ~ By Circumscr Rad lIE ® ~ By Side length lIE © .7l By Vertices -of1lE~---------------1@

Hinh 3.17

t~o hinh da giac noi ti~p duang tron, nhap sf> c~nh va ban kinh duang tron noi @ +-- ti~p.

® +-- t~o hinh da giac ngo~i ti~p duang tron, nhap sf> c~nh va ban kinh duang tron ngo~i ti~p.

© +-- t~o hinh da giac b~ng cach nhap sf> c~nh va do dai cho c~nh.

@ t~o hinh da giac b~ng cach nh~p cac dinh, luu y sau khi nh~p cac dinh xong thi

+-- ' bam OK.

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d) Bo cung gifra hai area El Modeling

El Create

I±l Keypoints I±l lines

El Areas

I±l Arbitrary I±l Rectangle

I±l Circle I±l Polygon

~ %¥i@lm

e) X6a area

Chi x6a area:

[AFILL T] Create Fillet Area

NAl ,NA2 Intersecting areas

RAD Fillet radius

OK Apply

Hinh 3.18

Ban kinh bo

Cancel Help

COMMAND: Main menu ~ Preprocessor ~ Modeling ~ Delete ~ Areas Only.

X6a ca key point va line tren area:

COMMAND: Main menu ~ Preprocessor ~ Modeling ~ Delete ~ Area and Below.

5) T~o kh8i (creat volume) a) Tqo tily y (arbitrary) El Modeling

El Create I±l Keypoints I±l lines I±l Areas El Volumes

El 'M mum ~ Through KP ,,01 By Areas ~-----'

Hinh 3.19

t~o volume qua tam key point cho trnac.

t~o volume giai h~n boi cac area cho trnac.

b) Tqo kh6i hinh h9P (block volume) ANSYS Main Menu


I±l Element Type I±l Real Constants I±l Material Props I±l 5ections

t~o block volume b~ng cach nhap toa do cua do dai hai c~nh cua m~t ph~ng hinh chu nhat, sau d6 nhap gia tri chi~u cao.

El Modeling EI Create

I±l Keypoints I±l lines I±l Areas EI Volumes

I±l Arbitrary

El m ,,01 By 2 Corners 8.: Z .;R By Centr ,Cornr ,Z +-_ ..... ~ By Dimensions

Hinh 3.20

t~o block volume b~ng cach nhap toa do Him va t~o do cua do dai hai c~nh cua m~t ph~ng hinh chu nhat, sau

d6 nhap gia tri chi~u cao.

t~o block volume b~ng cach nhap toa do cua do dai block volume thea phuang x, y va z so vai M toa do.

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c) Tqo kh6i hinh trl;l (cylinder volume)

El Volumes [±] Arbitrary J t~o cylinder volume b~ng cach nhap toa do Him, ban kinh va chi~u cao. [±] Block

El ~f!jIirm _ t~o cyl!nder volume r6ng b~ng cach nhap toa do Him, hai ban kinh ~ Solid Cylinder oJ r va chieu cao. Yl Hollow Cylinder ~ ~ Partial Cylinder .I(---------~@ ® ~ By End Pts & 2. .... I(~------------.

~ By Dimensions .... I(~---------------'©

Hinh 3.21

t~o mot ph~n cylinder volume b~ng cach nhap toa do Him, hai ban kinh, chi~u @ <IIf--- cao va hai g6c gi6i h~n.

® <IIf--- t~o mot ph~n cylinder volume b~ng cach nhap t~o do hai d~u duang kinh va

chi~u cao.

© <IIf--- t~o mot ph~n cylinder volume b~ng cach nhap toa do cua do dai cylinder volume thea phuang x, y va z so v6i M toa do.

c) Tqo kh6i hinh lang trl;l (prism volume) El Modeling

El Create [±] Keypoints [±] lines [±] Areas El Volumes

[±] Arbitrary [±] Block [±] Cylinder

[±] ~

Hinh 3.22

Lam gi6ng nhu ph~n t~o: "mq.t phiing da giac (polygon area)" nhung

cho them gia tri chi~o cao.

d) Tqo kh6i hinh cdu (sphere volume)

El Volumes [±] Arbitrary [±] Block

t~o sphere volume b~ng cach nhap toa do Him va ban kinh.

[±] Cylinder hi:;:: bC, 'h h~ d~ ~ , h . b' k' h [±] Prism t~o sp ere vo ume rong ang cac n ~p toa 0 tam va aI an III .

El~ [ ~ Solid Sphere ;=J- t~o sphere volume b~ng cach nhap toa do hai d~u duang kinh. ~ Hollow Sphere

~ By End Points ~ h" hi:;:: bC, 'h h~ d~ h . b' ~ By Dimensions I( t~o mot p an sp ere vo ume rong ang cac n ~p toa 0 aI an

kinh va hai g6c gi6i h~n so v6i M toa do. Hinh 3.23

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d) Tqo kh6i hinh can (cone volume)

EI Volumes I±I Arbitrary

I±I Block t~o cone volume b~ng cach nhap toa do hai ban kinh va chi~u cao cua

I±I Cylinder con I±I Prism

: itgre t~o mot ~h~n cone volume r6ng b~ng cach nhap toa do hai ban .?l By Picking I kinh, chieu cao va hai g6c gi6i h~n so v6i M toa do. ~ By Dimensions ~

Hinh 3.24

d) Tqo kh6i EI Volumes

I±I Arbitrary I±I Block I±I Cylinder I±I Prism I±I Sphere I±I Cone

~ rmm!

e) X6a volume

Chi x6a volume:

[TORUS] Create Torus by Dimensions

RADI Outer radius

RAD2 Optional inner radius

RADMAJ Major radius of torus

THETA 1 Starting angle (degrees)

THET AZ Ending angle (degrees)

OK Apply

,....--- ban kinh chinh.

,--- ban kinh trong cua 6ng.

, , ,. h {~IO ====: cac goc gm ~n Lr_o __ -----'

Cancel Help

Hinh 3.25

COMMAND: Main menu~Preprocessor~Modeling ~Delete~ Volumes Only.

X6a ca key point, line va area tren volume:

COMMAND: Main menu~Preprocessor~Modeling ~Delete~ Volume and Below.

6) Cae phep toaD (operate) a)Extrude

55

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ADVANCE C

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• Extrude areas

AN5Y5 Main Menu

~ Prererences 8 Preprocessor

t~o volume b~ng cach offset tu mot m~t ph~ng co trnac. Phuang offset 1a phap tuy~n cua m~t ph~ng.

I±I Element Type I±I Real Constants I±I Material Props I±I Sections 8 Modeling

I±I Create

t~o volume ph\! tu cac co trnac volume b~ng cach offset

tu cac m~t ph~ng tren volume co trnac. Co M sf> ti 1~ thea cac phuang x, y va z gifra m~t t~o thanh va m~t ban d~u.

8 Operate I d I I be, 'h ~ 8 EKtrude t~o cy in rica vo ume ang cac xoay mot area xung

~ Elem EKt Opts ~quanh mot tll)c. 8 m!!! ~ Along Normal

,,0l By XYZ Offset t~o volume b~ng cach quet mot area thea mot duang ~ About AKis ~ I I d~n. J1 Along Lines ",~:""------I.

Hinh 3.26

• Extrude lines

8 Operate t~o cylindrical area b~ng cach xoay mot line xung quanh mot 8 EKtrude I bI Elem EKt Opts tll)C.

I±I Areas 8_ ~ About AKis E---' I t~o area b~ng cach quet mot line thea mot duang d~n. ;n Along Lines +-----'

Hinh 3.27

• Extrude key points 8 Operate

8 EKtrude ~ Elem EKt Opts I±I Areas I±I Lines

t~o circular line b~ng cach xoay mot keypoint xung quanh mot

tll)c.

8 UHIIHtl :=J t~o line b~ng cach quet mot key point thea mot duang d~n . .Jl About AKis ,,0l Along Lines

Hinh 3.28

b) Extend Line 8 Operate

I±I EKtrude

~ §i§n,uut§ ~ Keo dai mot do~n th~ng t~i d~u mut cua chung. Hinh 3.29

56

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ADVANCE C

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c) Booleans

• Intersect El Operate

I±I Extrude tim giao nhau gifra cac volume.

?l Extend Line Jr El BOOlea.ns ~ tim giao nhau gifra cac area.

El Intersect

El Common tim giao nhau gifra cac line. ?l @Liim¥~ F Areas ~ Lines

Hinh 3.30

El Intersect I±I Common .I tim giao nhau tung doi mot gifra cac volume.

El i#MU ,. ,~. ~ . _ , ~ Volumes I tIm glao nhau tung d01 mot gma cac area. YI Areas "":I(~_...J.

~ Lines I( tim giao nhau tung doi mot gifra cac line.

Hinh 3.31

El Operate I±I Extrude Jil Extend Line tim giao nhau gifra area va volume. K~t qua cho ra la area. El Booleans

El @i§t!§M H, tim giao nhau gifra line va volume. K~t qua cho ra la line. I±I Common

'; pairwis~h I tim giao nhau gifra area va volume. K~t qua cho ra la "'~ Area Wit Vo ume

~ Line with Volume d I I line . }'l Line with Area .... I(~ ___ ...J.

Hinh 3.32

• Add El Operate

I±I Extrude cong cac volume rieng bi~t thanh mot volume duy nh~t. ~ Extend Line El Booleans ,

I±I Intersectdfrcong cac area rieng bi~t thanh mot area duy nhat.

El D ~ Volumes i I cong cac line rieng biet thanh mot line duy nh~t. "' . Areas I( . I . .. ~ Lines ... I(f------i

Hinh 3.33

57

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ADVANCE C

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• Subtract El Operate

I±I Extrude .? Extend Line El Booleans

tm mot ph~n cua mot volume tu cac volume khac. Volume nh~p tmac la volume bi tm, nh~p sau la volume tm.

I±I Intersect tm mot ph~n cua mot area tu cac area khac. Area nh~p tmac la I±I Add df b" h" l' , El Mad' area ~ tm, n ap sau a area tm.

J1 Volumes

J1 Areas J1 Lines ( tm mot ph~n cua mot line tu cac line khac. Line nh~p tmac la

Hinh 3.34 line bi tm, nh~p sau la line tm.

• Glue El Booleans

I±I Intersect I±I Add I±I Subtract I±I Divide dan dinh cac line, cac area

• Partition El Booleans

I±I Intersect I±I Add I±I Subtract I±I Divide

El :am ~ ho~c cac volume l~i vai nhau.

I±I Glue I±I Overlap

I±I ilffl ij itiffl chia cac line, cac area

~ ho~c cac volume vai nhau.

Hinh 3.35

• Divide EI Operate

I±I Extrude j1 Extend Line

EI Booleans

Hinh 3.36

chia volume b~ng area.

I±I Intersect Jfr chia volume b~ng m~t ph~ng lam vi~c. I±I Add

~ ~~~;: ~:;,::~ I i ~h:~:::e:~~:::: J" Mea by Volume ~::=J r JlI Area by Area ( .- chia area b~ng line. JlI Area by Line <I!E(-----....J.

JlI Area by WrkPlane ( L h' bCo ~ h;; l' .~ JlI Line by Volume ( C la area ang m~t pang am Vl~C .

.?I Line by Area ~ L '. Co

.F Line by Line ~L Chla lzne bang volune .

.?I Line by WrkPlane , }i1 Line into 2 ln's chia line bang area. JlI Line into N ln's , .fI Lines wi Options chia line bang line.

Hinh 3.37 chia line b~ng m~t ph~ng lam vi~c.

chia line thanh hai ph~n b~ng cach nh~p tllJc ti~p vao ch6 dn

chiao

chia line thanh hai ph~n nhi~u ph~n bang nhau. 58

TRUNG TÂM

ADVANCE C

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Engineering

Phân tích kỹ thuật với Ansys WorkBench 13 ( demo)