BAB V

ANALISA DATA, TABEL DAN GRAFIK

A. UNTUK ALIRAN LAMINAR

Analisa data :

Data No. = 3

Q ( debit ) dalam m3/s = 23 liter/m = 4.10-4 = 0,00038 m3/s

Temperatur = 28 ˚C = 273 + 28 = 301 ˚K

Viskositas kinematis = 20 . 10-6

ΔP dalam Pa = ( 0,054 – 0,099 ) .105 = 4100 Pa

ΔL dalam m = ( 3,39 – 0,75 ) m = 2,64 m

ρair berdasarka T = 996,4 kg/m2

ρoli ( SGoli = 0,835 ) = SGoli x ρair = 831,994 kg/m2

1. Kecepatan rata-rata aliran fluida dalam pipa ( V )

V = (m/s)

=

= 1,353 m/s

2. Bilangan Reynolds ( Re )

Re =

=

= 1285,060

3. Faktor Gesek ( fg )

fg =

=

= 0,050

4. Energi Kinetik Aliran fluida ( Ek )

Ek = (j/s) Apipa = π.D2/4

= = = 2,83385.10-

4 m2

= 0,289 J/s m = ρoli. V . Apipa

= 831,994. 1,353. 2,83385.10-4

= 0,319 kg/s

5. Menghitung Tegangan Geser ( σ0 )

σ0 = (N/m2)

=

= 8,097 N/m2

6. Kerugian Gesek ( hf )

hf = m

=

= 0,027 m

7. Kecepatan Aliran Fluida Maksimal ( Vmaks )

Vmaks = 2 . V (m/s)

= 2 . 1,353

= 2,705 m/s

8. Gaya Gesek pada Dinding Pipa

F = m . V (N)

= 0,319 . 1,353

= 0,432 N

9. Menghitung Distribusi Kecepatan ( Urn )

Urn = 2 . V . (m/s)

Ur0 = 2. 1,353 .

= 2. 1,353 .

= 2,705 m/s

Ur1 = 2. 1,353.

= 2. 1,353.

= 2,594 m/s

Ur2 = 2. 1,353.

= 2. 1,353.

= 2,273 m/s

Ur3 = 2. 1,353.

= 2. 1,353.

= 1,731 m/s

Ur4 = 2. 1,353.

= 2. 1,353.

= 0,974 m/s

Ur5 = 2. 1,353.

= 2. 1,353.

= 0 m/s

10. Distribusi Tegangan geser ( σrn )

σrn =

σr0 =

=

= 0 N/m2

σr1 =

=

= 3,239 N/m2

σr2 =

=

= 4,858 N/m2

σr3 =

=

= 4,858 N/m2

σr4 =

=

= 6,477 N/m2

σr5 =

=

= 8,097 N/m2

B. UNTUK ALIRAN TURBULEN

Analisa data :

Data No. = 10

Q ( debit ) dalam m3/s = 44 liter/m = = 7,33.10-4 m3/s

Temperatur = 30 ˚C = 273 + 30 = 303 ˚K

Viskositas kinematis = 17. 10-6 m2/s

ΔP dalam Pa = ( 0,270 – 0,114 ) .105 = 15600 Pa

ΔL dalam m = ( 3,39 – 0,75 ) m = 2,64 m

ρair berdasarka T = 996 kg/m2

ρoli ( SGoli = 0,835 ) = SGoli x ρair = 831,826 kg/m2

1. Kecepatan rata-rata aliran fluida dalam pipa ( V )

V = (m/s)

=

= 2,588 m/s

2. Bilangan Reynolds ( Re )

Re =

=

= 2892,206

3. Faktor Gesek ( fg )

fg =

=

= 0,022

4. Energi Kinetik Aliran fluida ( Ek )

Ek = (j/s) Apipa = π.D2/2

= = =

2,83385.10-4 m2

= 2,042 j/s m = ρoli. V . Apipa

= 831,827. 2,588. 2,83385.10-4

= 0,61 kg/s

5. Menghitung Tegangan Geser ( σ0 )

σ0 = (N/m2)

=

= 31,667 N/m2

6. Kerugian Gesek ( hf )

hf = m

=

= 0,05 m

7. Kecepatan Aliran Fluida Maksimal ( Vmaks )

Vmaks = U*.(2,44) Ln + 1,34 (m/s) U* =

= 0,180143. 2,44. Ln + 1,34 =

= 3,650 m/s = 0,180143

8. Gaya Gesek pada Dinding Pipa

F = m . V (N)

= 0,61 . 2,588

= 1,363 N

9. Menghitung Distribusi Kecepatan ( Urn )

Urn = Vmaks – 5,75 U* . (m/s)

Ur0 = 3,560 – 1,0358

= 3,560 - 0= 3,560 m/s

Ur1 = 3,560. – 1,0358

= 3,560 - 0,12067= 3,539 m/s

Ur2 = 3,560. – 1,0358

= 3,560 - 0,26076 = 3,401 m/s

Ur3 = 3,560. – 1,0358

= 3,71546 - 0,467378 = 3,203 m/s

Ur4 = 3,560. – 1,0358

= 3,560 – 0,8215798 = 2,865 m/s

Ur5 = 3,560. – 1,0358

= 3,71546 - 3,71546 = 0 m/s

10. Distribusi Tegangan geser ( σrn )

σrn =

σr0 =

=

= 0 N/m2

σr1 =

=

= 6,433 N/m2

σr2 =

=

= 12,667 N/m2

σr3 =

=

= 19 N/m2

σr4 =

=

= 25,333 N/m2

σr5 =

=

= 31,667 N/m2