Optimization of Heavy-Duty Diesel Engine Operating Parameters Using Micro-Genetic Algorithms

C o p y r ig h t 2 0 0 5 K S A E 1 2 2 5 - 6 3 8 2 / 2 0 0 5 / 0 7 4 - 1 4 T r a ns a c tio ns o f K SA E , V o l. 1 3 , N o . 2 , p p .1 0 1 -1 0 7 (2 0 0 5 )

N o m e nc lature ^{1 )}

A T D C : a fte r to p d e a d c e n te r

B S F C : b ra k e s p e c ific fu e l c o n s u m p tio n , g /k W -h r B T D C : b e fo re to p d e a d c e n te r

E V O : e x h a u s t v a lv e o p e n IV C : in ta k e v a lv e c lo s e

.G A : m ic ro g e n e tic a lg o rith m S O I : s ta rt o f in je c tio n

1 .

*

T o w h o m c o rr e s p o n d e n c e s h o u ld b e a d d re s s e d . m a n s h ik @ e r c .w is c .e d u

S o o t N O x .

.

.

C F D .

.

*

M ike P . L ie c hty R o lf D . R e itz

Engine Research Center, University of Wisconsin-Madison

Optimization of Heavy-Duty Diesel Engine Operating Parameters Using Micro-Genetic Algorithms

Manshik Kim

Mike P. Liechty Rolf D. Reitz

Engine Research Center, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706, USA (Received 6 September 2004 / Accepted 6 December 2004)

A b s trac t : In th is p a p e r, o p tim iz e d o p e ra tin g p a ra m e te rs w e re fo u n d u s in g m u lti-d im e n s io n a l e n g in e s im u la tio n s o ftw a re (K IV A -3 V ) a n d m ic ro -g e n e tic a lg o rith m fo r h e a v y d u ty d ie s e l e n g in e . T h e e n g in e o p e ra tin g c o n d itio n c o n s id e re d w a s a t 1 ,7 3 7 re v /m in a n d 5 7 % lo a d . E n g in e s im u la tio n m o d e l w a s v a lid a te d u s in g a n e n g in e e q u ip p e d w ith a h ig h p re s s u re e le c tro n ic u n it in je c to r (H E U I) s y s te m . T h re e im p o rta n t p a ra m e te rs w e re u s e d fo r th e o p tim iz a tio n - b o o s t p re s s u re , E G R ra te a n d s ta rt o f in je c tio n tim in g . N u m e ric a l o p tim iz a tio n id e n tifie d H C C I-lik e c o m b u s tio n c h a ra c te ris tic s s h o w in g s ig n ific a n t im p ro v e m e n ts fo r th e s o o t a n d N O x e m is s io n s . T h e o p tim iz e d s o o t a n d N O x e m is s io n s w e re re d u c e d to 0 .0 0 5 g /k W -h r a n d 1 .3 3 g /k W -h r, re s p e c tiv e ly . M o re o v e r, th e o p tim u m re s u lts m e t E P A 2 0 0 7 m a n d a te s a t th e o p e ra tin g p o in t c o n s id e re d .

K e y w o rd s : O p tim iz a tio n ( ), M ic ro g e n e tic a lg o rith m ( ), K IV A -3 V c o d e (K IV A -3 V ),

D ie s e l e n g in e ( )

M ik e P . L ie c h ty R o lf D . R e itz

.

.

,

W ic k m a n

C F D .

K IV A -3 V

. K IV A -3 V

.

2 .

2 .1

, E n g in e R e s e a rc h C e n te r (U W -M a d is o n ) ,

, , K IV A -3 V

.

K H -R T

S h e ll .

S o o t

H iro y a s u

N a g le a n d S tric k la n d -C o n s ta b le

N O x Z e l’d o v ic h

1 0 )

.

. 2 .4 4

. 1 ,7 3 7 re v /m in ,

5 7 % (M o d e 5 ) .

6 0 .1 5 8 m m

. (IV C -E V O )

6 6 0 °

. C

H

M o d e 5 .

.

F ig . 1

B T D C 3 0 ° . T a b le 1

.

Fig. 1 Computational grid for the Caterpillar engine at BTDC 30°

Table 1 Specifications of heavy duty diesel engine and injector

E n g in e C a te rp illa r 3 4 0 1 S C O T E B o re (m m ) × S tro k e (m m ) 1 3 7 .2 × 1 6 5 .1

C o m p re s s io n ra tio 1 6 .1 :1 D is p la c e m e n t v o lu m e ( ) 2 .4 4 P is to n g e o m e try M e x ic a n h a t N u m b e r o f h o le s 6

D ia m e te r o f h o le (m m ) 0 .1 5 8 In je c tio n a n g le (d e g .) 1 2 8 In je c te d m a s s (m g ) 1 3 2 .2

2 .2

S e n e c a l

.G A (M icro

g e n e tic a lg o rith m ) .

.

0 1

. .G A 5

1

(E litis t p re s e rv in g

s e le c tio n ) 4

4 C P U

.

.

(1)

N O x S o o t

. o

E P A 2 0 0 7 .

(P M : 0 .0 1 3 4 g /k W -h r, N O x + H C : 1 .7 9 6 g /k W -h r, B S F C : 2 5 6 g /k W -h r)

, .

(T o u rn a m e n t s e le c tio n )

(C ro s s o v e r) .

. , E G R

T a b le 2 .

Table 2 Variation of engine operating parameters B o o s t p re s s u re (k P a ) 1 3 0 ~ 2 2 0 , 4 s te p s E G R ra te (% ) 0 .0 ~ 5 0 .0 , 3 2 s te p s S O I tim in g (A T D C d e g .) -6 0 .0 ~ 2 0 .0 , 3 2 s te p s

3 .

F ig . 2 K IV A -3 V . E G R 5 0 %

Fig. 2 Engine laboratory setup with dilution tunnel and EGR system

.

S o o t, H C , N O x

. E G R 0 %

-3 .5 ° A T D C 5 .5 ° A T D C 2 ° C A

-5 .5 ° A T D C E G R 0 %

~ 2 3 .5 % .

4 .

4 .1 F ig . 3

. F ig . 3 (a ) 3 (b ) E G R

.

.

. F ig . 4

.

S o o t N O x

.

M an s h ik K im M ik e P . L ie c h ty R o lf D . R e itz

0 2 4 6 8 10

-0.01 0 0.01 0.02 0.03 0.04 0.05 0.06

-60 -30 0 30 60 90

Timing swing SOI 3.5 deg. ATDC Calculation

Experiment

Pressure (MPa) Normalized HRR

Crank angle (ATDC deg.) (a)

0 2 4 6 8 10

-0.01 0 0.01 0.02 0.03 0.04 0.05 0.06

-60 -30 0 30 60 90

EGR swing EGR rate 20.2 % Calculation

Experiment

Pressure (MPa) Normalized HRR

Crank angle (ATDC deg.)

(b)

Fig. 3 Cylinder pressure and heat release rate comparison between the experiment and calculation

0 0.5 1 1.5 2 2.5

0 5 10 15 20 25 30

Timing swing (expt.) Timing swing (cal.) EGR swing (expt.) EGR swing (cal.)

Soot (g/kg-f)

NOx (g/kg-f)

Fig. 4 Comparison of emission characteristics

4 .2 F ig . 5

0 100 200 300 400 500 600

0 50 100 150 200

Maximum merit value

Generation number Fig. 5 Mode 5 three-factor GA merit vs. generation

-5 0 5 10 15 20

-600 0 600 1200 1800 2400

-60 -40 -20 0 20 40 60

Pressure (MPa) Rate of heat release (J/deg.)

Crank angle (ATDC deg.)

Fig. 6 Cylinder pressure and heat release rate of the optimum case

. 5

7 4

. 7 4

.

2 2 0 k P a , E G R 4 6 .6

% , -6 0 ° A T D C . F ig . 6

.

. S o o t

E G R N O x

(S o o t : 0 .0 0 5 g /k W -h r, N O x + H C : 1 .3 3 g /k W -h r). F ig .

7 (a ) N O x + H C - S o o t, (b )

N O x + H C - B S F C

O p tim iz atio n o f H e av y - D u ty D ie s e l E n g in e O p e ratin g P aram e te rs U s in g M ic ro - G e n e tic A lg o rith m s

. E P A

2 0 0 7

.

N O x E G R

N O x S o o t H C C I

-6 0 ° A T D C . F ig . 8

. -6 0 ° A T D C -2 7 ° A T D C

. 1 5 0 M P a

.

0 0.05 0.1 0.15

0 2 4 6 8

Soot (g/kW-hr)

NOx+HC (g/kW-hr)

EPA 2007 Mandates

(a)

175 200 225 250 275

0 2 4 6 8

BSFC (g/kW-hr)

NOx+HC (g/kW-hr)

EPA 2007 Mandates

(b)

Fig. 7 (a) Soot vs. NOx + HC (b) BSFC vs. NOx + HC data from the optimization study including the optimi- zation start point, intermediate optimum and global optimum (not all points are shown due to scaling)

F ig . 9 ~ F ig . 1 1

, N O x

Fig. 8 Predicted fuel vapor concentration for the optimum case (-40° ATDC, -30° ATDC, -27° ATDC and -24°

ATDC from top to bottom)

Fig. 9 In cylinder temperature distribution at (a) -10° ATDC

(b) TDC (c) 10° ATDC

M ik e P . L ie c h ty R o lf D . R e itz

Fig. 10 In cylinder NOx distribution at (a) -5° ATDC (b) TDC (c) 10° ATDC

Fig. 11 In cylinder soot distribution at (a) -10° ATDC (b) TDC (c) 10° ATDC

S o o t .

. N O x

S o o t ,

S o o t .

.

S o o t N O x H C C I

. 4 6

. 4 6 7 4

1 9 0 k P a -5 2 ° A T D C

1 6 M P a . .G A

.

5 .

.G A . 1 )

K IV A -3 V .G A

.

2 ) 1 ,7 3 7 re v /m in , 5 7 %

2 2 0

k P a , E G R 4 6 .6 % , -6 0

A T D C

H C C I .

3 ) S o o t

0 .0 0 5 g /k W -h r, N O x 1 .3 3 g /

k W -h r .

4 )

.

.

P o s t-d o c . .

R e fe re nc e s

1 ) D . E . G o ld b e r g , G e n e tic A lg o r ith m s in S e a r c h , O p tim iz a tio n , a n d M a c h in e L e a r n in g , A d d is o n - W e s le y , 1 9 8 9 .

2 ) P . K . S e n e c a l a n d R . D . R e itz , “ S im u lta n e o u s R e d u c tio n o f E n g in e E m is s io n s a n d F u e l C o n s u m p tio n U s in g G e n e tic A lg o r ith m s a n d M u lti- D im e n s io n a l S p r a y a n d C o m b u s tio n M o d e lin g ,” S A E 2 0 0 0 - 0 1 - 1 8 9 0 , 2 0 0 0 .

3 ) D . D . W ic k m a n , H . Y u n a n d R . D . R e itz ,

“ S p lit- S p r a y P is to n G e o m e tr y O p tim iz e d f o r H S D I D ie s e l E n g in e C o m b u s tio n ,” S A E 2 0 0 3 - 0 1 - 0 3 4 8 , 2 0 0 3 .

4 ) T . S . K im , D . H . L e e a n d J . J . K im , “ O p tim u m D e s ig n o f S u s p e n s io n S y s te m s U s in g a G e n e tic A lg o r ith m ,” T r a n s a c tio n s o f th e K S A E , V o l.8 , N o .5 , p p .1 3 8 - 1 4 7 , 2 0 0 0 .

5 ) A . A . A m s d e n , “ K I V A - 3 V : A B lo c k - S tr u c - tu r e d K I V A P r o g r a m f o r E n g in e s w ith V e r tic a l o r C a n te d V a lv e s , L o s A la m o s N a tio n a l L a b o - r a to r y R e p o r t N o . L A - 1 3 3 3 - M S , 1 9 9 7 .

6 ) M . A . P a tte r s o n a n d R . D . R e itz , “ M o d e lin g th e E f f e c ts o f F u e l S p r a y C h a r a c te r is tic s o n D ie s e l E n g in e C o m b u s tio n a n d E m is s io n s ,” S A E 9 8 0 1 3 1 , 1 9 9 8 .

7 ) S . C . K o n g , Z . H a n a n d R . D . R e itz , “ T h e D e v e lo p m e n t a n d A p p lic a tio n o f a D ie s e l I g n itio n a n d C o m b u s tio n M o d e l f o r M u ltid i- m e n s io n a l E n g in e S im u la tio n s ,” S A E 9 5 0 2 7 8 , 1 9 9 5 .

8 ) K . N is h id a a n d H . H ir o y a s u , “ S im p lif ie d T h r e e - D im e n s io n a l M o d e lin g o f M ix tu r e F o r m a tio n a n d C o m b u s tio n in a D . I . D ie s e l E n g in e ,” S A E 8 9 0 2 6 9 , 1 9 8 9 .

9 ) J . N a g le a n d R . F . S tr ic k la n d - C o n s ta b le ,

“ O x id a tio n o f C a r b o n b e tw e e n 1 0 0 0 - 2 0 0 0 ° C ,”

P r o c . o f th e F if th C a r b o n C o n f ., V o l.1 , p .1 5 4 , 1 9 6 2 .

1 0 ) C . T . B o w m a n , “ K in e tic s o f P o llu ta n t F o r m a - tio n a n d D e s tr u c tio n in C o m b u s tio n ,” P r o g r e s s o f E n e r g y C o m b u s tio n S c ie n c e , V o l.1 , p p .3 3 - 4 5 , 1 9 7 5 .

1 1 ) D . D . W ic k m a n , “ H S D I D ie s e l E n g in e C o m - b u s tio n C h a m b e r G e o m e tr y O p tim iz a tio n ,” P h . D . T h e s is , U n iv e r s ity o f W is c o n s in - M a d is o n , 2 0 0 3 .

1 2 ) E m is s io n S ta n d a r d s : U S A H e a v y - D u ty T r u c k

a n d B u s E n g in e s : h ttp ://w w w .d ie s e ln e t.c o m /

s ta n d a r d s /u s /h d .h tm l