PMグループ

Cross-ministerial Strategic Innovation Promotion Program: SIP「革新的燃焼技術」公開シンポジウム＠一橋大学一橋講堂 2017年7月6日

制御チーム 大分大学理工学部橋本 淳

「ガソリンエンジンでの低温始動時PM/PN予測モデルの構築」

予定，将来展望

研究概要 目的

研 究 成 果

課 題

直噴ガソリンエンジン冷間始動時のプール燃焼条件に対応したPM/PN排出量予測モデルを構築・検証し，実用設計計算を可能とする．

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

i-C8H18CRECK A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3/5

A4/5

B1/5

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

i-C8H18KM1 A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3

A4

A5x5

A6x5

A7

A7 Original

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

i-C8H18P.AN Mech A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3x100

A4x100

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

PMGS3CRECK A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3/30

A4/10

B1/5

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

PMGS3KM1 A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3/5

A4/5

A5

A6

A7

4.0 6.0 8.00.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

[110-6

]

Distance [mm]

Mo

le F

ract

ion

[-]

PMGS3P.AN Mech A3

Exp. Cal.

A4

A5x5

A6x5

A7x5

A3/15

A4/15

i-C8H18, CRECK i-C8H18, KM1 i-C8H18, P.AN M

PMGS3, CRECK PMGS3, KM1 PMGS3, P.AN M

4.0 6.0 8.00.0

1.0

2.0

3.0

[110-6

]

Par

ticl

e V

olu

me

Fra

ctio

n [

cm3/c

m3]

Distance [mm]

CRECKx10:

KM1/10:

PANMx104:

i-C8H18

4.0 6.0 8.00.0

1.0

2.0

3.0

[110-6

]

Par

ticl

e V

olu

me

Fra

ctio

n [

cm3/c

m3]

Distance [mm]

CRECKx5:

KM1/10:

PANM/10:

PMGS3

i-C8H18 PMGS3

0.0 1.0 2.0 3.0

50

100

Time after SOI [ms]

Pe

ne

tra

tio

n L

en

gth

[m

m]

:Experiment:Calculation

12

0 m

m

0 1 2 3 4 5 60

10

20

30

40

50

0 1 2 3 4 5 60

10

20

30

40

50

-30 deg. ATDC

-15 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

0 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

15 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

30 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

45 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

60 deg. ATDC

75 deg. ATDC

90 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

0 1 2 3 4 5 60

10

20

30

40

50105 deg. ATDC

120 deg. ATDC

0 1 2 3 4 5 60

10

20

30

40

50

0 1 2 3 4 5 60

10

20

30

40

50

0 30 60

0.05

0.10

0.15

Crank Angle [deg. ATDC]

So

ot

[mg

]

:Experiment:Calculation x 3

-180 -120 -60 0 60 120 1800.0

1.0

2.0

3.0

Crank Angle [deg. ATDC]

Pre

ssu

re [

MP

a]

:Experiment:Calculation

すすモデルの改良と検証

Bore [mm] 78

Stroke [mm] 67

Displacement Volume [cm3] 320

Compression Ratio [-] 9

Engine Specification

Engine Speed [rpm] 600

Intake Valve Close [deg. ATDC] -180

Injection Pressure [MPa] 5

Injection Timing [deg. ATDC] -27

Injection Duration [deg.] 17

Spark Timing [deg. ATDC] -5

Intake Pressure [MPa] Time Varying Measured Value

Intake Temperature [K] 329

Global Equivalence Ratio [-] 1.1

Fuel PM Surrogate 3 Species

i -C8H18 / 65 %

n -C7H16 / 10 %

Toluene / 25 %

Experimental Condition

Solver ANSYS Forte R18.1

Turbulence model RNG k-e model

Spray atomization and droplet breakup model KH-RT hybrid breakup model

Droplet size distribution / Rosin-Rammler Distribution modified by OkayamaU

Vaporization model Discrete Multi-Component fuel vaporization model

Wall film model O'Rourke and Amsden model

Ignition model Discrete Particle Ignition Kernel flame model

Flame propagation Model G-Equation model

Laminar flame speed / Dynamic flame speed table

Soot model Method of moments

Gas phase reaction / KAUST 1 modified by OitaU, 233 species and 1375 reactions

Surface reaction / KAUST 2 modified by NihonU, 8 pre cursors

Mesh control Global mesh size / 2.0 mm

Solution Adaptive Mesh, gradient of velocity field / 0.5 mm

Solution Adaptive Mesh, gradient of fuel field / 0.5 mm

Solution Adaptive Mesh, gradient of temperature field / 0.5 mm

Numerical Method

ペネトレーションと噴霧形状

急速圧縮膨張装置

定容器（大気圧）

非燃焼場における当量比分布

火炎伝ぱと筒内圧力観測視野内のすす生成挙動

Fuel

O2

CO2

H2O

10nm～ 100nm～0.5nm～

Gas Phase KineticsHydrocarbons

Gas Phase Kinetics Hydrocarbons

MoM PAH MoM Soot

MoM Soot

MoM (only) Soot

Sectional Method PAH-Soot-Aggregates

Sectional Method Soot-Aggregates

Aggregates

AggregatesGas Phase KineticsPAH

? ?

Model HPC Systems HPC5000

CPU Xeon E5-2697v2 (2.7 GHz, 12 Core), 2 CPU

Memory 128 GB

Parallel number 24

Total wall clock time 5 days

from intake stroke to expansion stroke

Wall clock time in chemistry 1 day

Maximum memory usage 29 GB

Maxiumu cell number approx. 900,000

Computational Resources

• 燃料組成に対して柔軟に対応できるモデル• 火神の検証（基本モデルは組み込み済み）

• マスターモデルとリダクションモデル• 単気筒エンジンの統合シミュレーション

0.0E+00

1.0E-13

2.0E-13

3.0E-13

4.0E-13

5.0E-13

0.0E+00

1.0E+07

2.0E+07

3.0E+07

4.0E+07

5.0E+07

6.0E+07

7.0E+07

8.0E+07

9.0E+07

1.0E+08

0.0E+00 1.0E-05 2.0E-05 3.0E-05 4.0E-05 5.0E-05

Par

ticl

e V

olu

me

Frac

tio

n [

cm3

/cm

3]

Par

ticl

e N

um

ber

Den

sity

[#/

cm3

]

Time [s]

PNDとPVF

CKP-PND HNC-PND CKP-PVF HNC-PVF

Burnout Model未導入ここはその影響

大分大・日大・横国大・群大

大分大・岡大・群大・北大 大分大・明治大・日大

大分大・明治大・日大 大分大・明治大・日大・横国大・群大

大分大・日大・横国大・群大・JAXA

大分大・千葉大・日大・横国大・群大

燃料組成変動を考慮し，すすモデルを構築した ペネトレーションの検証を行った 当量比分布の検証を行った 燃え広がりおよび圧力変化の検証を行った 観察視野内におけるすす生成挙動を再現した

-10

0

10

20

30

40

50

-60 -30 0 30 60 90 120 150 180

Ap

par

ant

Hea

t R

elea

se R

ate

[J/d

eg.]

Crank Angle [deg. ATDC]

No. 2 No. 3 No. 4 No. 5 No. 6 No. 7 No. 8

1.0E+00

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

1.0E+06

1.0E+07

1 10 100 1000

Log

PN

[-]

Log D [nm]

No. 2 No. 3 No. 4 No. 5 No. 6 No. 7 No. 8

熱発生率

粒径分布