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8/9/2019 15089 Numerical Modeling of Combustion -Gasification
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Numerical Model ing of Combustion and Gasif icat ion Processes using the Discrete Part ic le
Method
Mehrdad Shahnam Madhava Syamlal
Fluent Incorporated
3647 Collins Ferry Road Suite A
Morgantown WV 26505
Daniel Cicero
Department of Energy National Energy Technology Laboratory
P.O. Box 880
Morgantown WV 26507
A B S T R A C T
A methodology for model ing combust ion and gasi f icat ion
proce sses in a transport gasifier is describ ed in this paper. A
t ranspor t gasi f ier i s an eff icient means of conver t ing carbon-
based feedstock in to synthesis gas , which can be used to
produce high-value l iquid fuels , value-added chemicals , and
hydrogen for fuel cel ls amo ng other th ings. The system
consists of three mai n parts: mixing zone, riser, and the solids
return loop. The t ranspor t gasi f ier operates as a comb ustor at
startup. Coal is injected into the syste m at the top part of the
mixing zone. The devolat i l ized species are col lected and the
remaining unburned carbon in the coal , char , i s redi rected back
to the uni t. Addi t ional combu st ion takes p lace at the lower
por t ion of the mixing zon e where the recycled char and hot
burner ai r meet . As oxy gen in the system is depleted , the uni t
moves f rom the combustor mode in to gasi f icat ion mode.
Steam is in jected in to the system to prom ote s team gasi f icat ion
of hot recycle char . Addi t ional gasi f icat ion can take p lace wi th
carbon dioxide in the gas s tream. The gas-sol id f low regimes
encountered in the system vary f rom locat ion to location. Flow
in the recycle char return loop can be character ized as a dense
f low.Flow in the mixing zone and the r i ser can be character ized
as a dilute flow for input condit ions under consideration. The
goal of th is manus cr ip t i s to descr ibe the ap proach taken to
model the combust ion and gasi f icat ion process in the d i lu te
f low zones encountered in the mixing zone a nd the r i ser . I t is
assumed that the unit has reached i ts steady state condit ion.
Ti me averaged equat i ons o f mass , momen t um, energy , and
species t ranspor t are solved for the gaseous phase wi th
F L U E N T TM sof tware. The sol id par t icle f low is s imulated
using the discrete part icle metho d. In this approac h, the solid
phase equat ions of mom ent um and energy are solved in a
Lagrang ian f rame of reference. Heat , mass t ransfer, and
momen t um exchange t o and f rom t he par t i c l es a r e compu t ed
and added to the cont inuos phase as a source or s ink term
Coal devolat i l izat ion , gasi f icat ion and combust ion react ions
were included in the model through user def ined funct ions.
The discrete par t icle method works wel l when the f low is
sufficiently dilute that part icle-part icle interactions can be
neglected . This impl ies that the f low volume f ract ion needs to
be as low as 10-12 . Alth oug h the flow condit ions in the
current s tudy have volume f ract ions lower than the
recommended volume f ract ion l imi t , we found that the large
mass f low rate of par t icles relat ive to the mass f low rate of the
gaseous phase causes numerical instabi l i t ies . A novel approach
has been implemented which l imi ts the heat t ransfer rates
betwe en the two phases and s tabi lizes the calculat ions. The gas
phase tempera ture f ield obtained wi th the modif ied d iscrete
par t icle method agrees fav orably wi th avai lable data.
I N T R O D U C T I O N
Coal i s the most widely used sol id fuel consumed by the
powe r generat ion indust ry . Because of economic and
envi ronmental considerat ions, the need exis t s to improve the
eff iciency of coal comb ust ion process . Computat ional Fluid
Dynamics(CFD) has widely been used as a tool to opt imize
equipment designs and combust ion eff iciency of coa
combustors . An effect ive technique in model ing of coa
combust ion has been the Lagrangian discrete phase technique.
In th is approach, coal par t icles o f known size d is t r ibut ions and
proper t ies are in jected in to the combustor and t racked in a
Proceedings of2000 International Joint Power Generation Conference
Miami Beach, Florida, July 23-26, 2000
IJPGC2000-15089
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L a g ra ng i a n f a s h i on t h roughou t t h e c om pu t a t i ona l dom a in .
Hea t and mass t rans fe r to / f rom pa r t i c le s a re ca lcu la ted a long
each t ra jec to ry and a re used a s the coupl ing mechanism
be tw een the gas phase and the so l id phase . A ma jor
as sumpt ion in the Lagrang ian d i s c re te phase mode l i s tha t the
in te rac t ion of so l id pa r t i c le s i s neg lected . As a re su lt th is
approach i s on ly app l icab le to d i lu te f lu id -pa r t i c le f lows w here
the so l id phase vo lume f rac t ion i s l e s s than 10%. S ince mos t
coa l burn ing com bus tors a re ope ra ted in the d i lu te f low reg ion ,
(e . g . low vo lume f rac t ion and low so l id - to -gas phase mass
load ing) , the Lagrang ian d i s c re te phase mode l can be used to
cap ture the rma l and hydrodynamic cha rac te r i s t i c s o f typ ica l
coa l burn ing com bus tors . How ever , i f so l id to gas phase mass
load ing i s h igh enough , th i s mode l may ove r -pred ic t the
• t empera tu re f ie ld . This work has bee n unde r taken to fo rmula te
and implement a me thodology which wi l l e l im ina te the
tempera ture ove rpred ic t ion encounte red in Lagra ng ian d i s c re te
phase mode l .
Coupled S olution
In the Lagrang ian d i s c re te phase mode l , pa r t i c le
mo me ntum and ene rg y equa t ions a re so lved a long each pa r t i c le
t ra jec to ry . Cons ide r the pa r t i cle ene rgy equa t ion :
d T p = h a p ( T f - T p + S p
(1)
mpCp d'--7
W here the f i r s t te rm o n the r igh t hand s ide i s the in te rphase
hea t t rans fe r be tween the so l ids and the sur rounding gas and
the s econd te rm on the r igh t ha nd s ide , Sp . represen t s any
addi t iona l hea t source o r s ink con t r ibu t ions . Dur ing the t ime
in tegra t ion of the pa r t i c le ene rgy equa t ion in each
compu ta t iona l con t ro l vo lume , the loca l gas phase t empera tu re ,
T f
i s he ld cons tan t . I f the hea t t rans fe r ra te be tween the two
phases i s sma l l , keep ing the gas phase t empera tu re cons tan t
dur ing t ime in tegra t ion of pa r t i c le ene rgy equa t ion i s
accep tab le . How ever , i f the hea t trans fe r rate be tween the so l id
and the gas phase i s l a rge , ho ld ing the loca l gas t empera tu re
cons tan t dur ing t ime in tegra t ion of equa t ion (1 ) l eads to
exces s ive ene rgy t rans fe r be tween the pa r t i c le s and the gas
phase . The exces s ive ene rgy t rans fe r causes unrea l is t i c ho t o r
co ld spo t s in the gas t em pera tu re f i e ld .
I t i s pos s ib le to p reven t such unrea l i s t i c hea t t rans fe r
be tween the phases by a t igh te r the rma l coupl ing be tween the
so l id phase and the gas phase . The ma in idea i s to so lve the
f lu id -phase ene rgy equa t ion coupled wi th the pa r t i c le -phase
ene rgy equa t ion du r ing the pa r t i c le - t rack ing phase on a ce l l -by-
ce l l bas i s. To ach ieve th i s goa l , f i r s t cons ide r the f lu id phase
ene rgy equa t ion :
,O f Cpf v f .V T f = V .k f V T f -F J transfer+ S f ( 2 )
W h e r e Y t r a n s f e r i s the in te rphase hea t t rans fe r be tween the
so l id and the gas phases . By in tegra t ing th i s equa t ion ove r a
con t ro l vo lume , the d i s c re f i zed fo rm of the f lu id phase en e rgy
equa t ion i s ob ta ined :
a c ( T f ) C = Z a n b ( T f ) n b + b + J tra nsfe rA V C ( 3 )
nb
Where ac , anb and b are the center coeffic ient , the
ne ighbor ing coe f f i c ien t , and the source t e rm respec t ive ly and
A V e i s ce l l vo lume . The pa r t i c le ene rgy equa t ion is so lved by
tak ing seve ral t ime s teps wi th in a computa t iona l ce l l. The
d isc re t ized fo rm of equa t ion (1) ov e r a time s tep i i s
i
m p C p T ~ T ~ - - h A p ( T f - T ~ ) + S p
A t ~
(4)
The in te rphase hea t t rans fe r fe l t by the f lu id phase f rom the
part ic le t rack ove r t ime s tep i is
J~r ans f erAVc = h A p ( T t~ T f ) (r h ~ / /~ p ) A t i
( 5 )
where / rhP /m ] i s the num ber f l °w ra te ° f pa r t i cle s f ° r
the pa r t i c le t rack under cons ide ra t ion . The accumula ted
in te rphase hea t t rans fe r f rom a l l the t ime s teps N with in the
ce l l can be found by in tegra t ing ( summing) the above
express ion:
i=N
J, ,~, , :erA V e = Z h A p (T ip T I ) (r h ~ /~ p ] A t i
(6)
i=1
By combin ing equa t ions (3 ) and (6 ) , the fo l lowing
disc re t ized fo rm o f the f lu id phase ene rgy equa t ion i s ob ta ined :
i=N
a c T = Z a n b ( Tf )nb + b + Z h A p ( T] - T f) lr h P ~ m p ) A t i
nb i=1
( 7 )
Equa t ions (4 ) and (7 ) fo rm a s e t o f N + 1 equa tions fo r
T f
a nd
T i
( i = 1 , N ) . S imul taneous so lu t ion of the above
P
equa t ions wi l l ensure tha t the numer ica l so lu t ion wi l l no t
pe rmi t any unrea l i s t i c hea t t rans fe r. The above eq ua t ion s e t can
be eas i ly gene ra l i zed fo r mul t ip le pa r ti c le t racks. How ever ,
so lv ing such an equa t ion s e t i s cpu in tens ive and imprac t i ca l .
An a l t e rna te approach fo r so lv ing equa t ions (4 ) and (7 ) i s
desc r ibed be low.
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Temp erature Limiter Algorithm
I t i s p roposed t ha t dur i ng t he pa r t i c l e t r ack ing ca l cu l a t i on ,
t he i n t e rphase hea t t r ans f e r t e rm,
J t r a n s f e r be
b o u n d e d b y a
l o w e r a n d a n u p p e r th r e s h o l d w h i c h a r e c h a r a c t e r iz e d b y
m i n i m u m a n d m a x i m u m c o n v e c t i v e he a t t r an s f e r co e f f ic i e n t
b e t w e e n th e g a s a n d s o li d p h a s e s . T h e m i n i m u m i n t e rp h a s e
h e a t t r a n s f e r t e r m o c c u r s w h e n t h e h e a t t r a n s f e r c o e f f i c ie n t , h ,
a p p r o a c h e s z e r o . T h e p a r t ic l e te m p e r a t u r e c a n b e c a l c u l a te d
f r o m ( 4 ) to b e
S ; A t i
T ; ] mm
T; 1
I - -
(8)
m p C p
T o d e t e r m i n e t h e u p p e r t e m p e r a t u r e t h r e s h o l d w h e n t h e
c o n v e c t i v e h e a t t ra n s f e r c o e f f i c i e n t a p p r o a c h i ts m a x i m u m , a n
aux i l i a ry gas t emp era tu r e fi e l d , T} , is de fm ed . The aux i l i a ry
gas t empera tu r e can i nc r ease o r dec r ease dur i ng pa r t i c l e
t r ac k i n g c a l c u l a ti o n s d e p e n d i n g o n w h e t h e r h e a t i s t r a n s f e r re d
t o o r f r o m t h e g a s p h a s e . T h e d i s c r e t iz e d p a r t ic l e e n e r g y
equa t i on i n te rms o f t he aux i l i a ry gas t empe ra tu r e i s
i
m p C p T ; T ; - I - h A p : - T ; ) S p
A t ~
(9)
Us ing t he f l u i d phase ene rgy equa t i on , ( 7 ) , t he aux i l i a ry
gas t empe ra tu r e can be w r i t t en a s:
i N
a c T : = Z a n b T f ) n b + b + Z h A p T ; - T f ) l h P ~ m I t i
n b
i=1 P
Or
a c T } = a c r : - 1 + h A p T ; - T f ) p
( 10)
w h e r e
a c t ~ = Z a n b ( T f )nb + b
n b
C o m b i n i n g e q u a t i o n s ( 9 ) a n d ( 1 0 ) a n d n o t i n g t h a t a t
m a x i m u m i n te r p h a s e h e a t t r a n s f e r c o n d i ti o n , b o t h t h e p a r t i c l e
t e m p e r a t u r e a n d t h e a u x i l i a r y g a s t e m p e r a t u r e a p p r o a c h t h e
same equ i l i b r i um va lue , Tp = T} ,
T; Jm~ --
c ( r h p / ~ T i - l+ S ; ( r h P ~ m e ) A t i
a c T : - ' + m p
k
/ m p J P
( 11)
E q u a t i o n s ( 8 ) a n d ( 1 1 ) c a n b e u s e d a s l o w e r a n d u p p e r
boun ds fo r t he pa r t i c l e t emp era tu r e f i e ld . I n t he t echn iqu e
d e s c r i b e d a b o v e , t h e l o w e r a n d u p p e r p a r t i c l e t e m p e r a t u r e
t h r e sh o l d s a r e o n l y u s e d i f p a r ti c l e t e m p e r a t u r e c a l c u l a te d b y
equa t i on (4 ) a r e ou t s i de o f t he t emp era tu r e l imi t s.
Oxidizer Limiter Algorithm
I n t h e L a g r a n g i a n d i s c r e t e p h a s e m o d e l , g a s e o u s p h a s e
prope r t i e s , ( i .e . ox id i ze r mass f r ac t i on) a r e he ld cons t an t dur i ng
pa r t i c l e t r a j ec t o r i e s ca l cu l a t i ons . For com bus t i ng pa r t i c l e s th i s
a s s u m p t i o n w i l l l e a d t o a n e x c e s s i v e a m o u n t o f o x i d i z e r b e i n g
ava i l ab l e f o r com bus t i on dur i ng pa r t i c l e t r a j ec t o ry ca l cu l a ti ons
i n pa r t i cu l a r i f mu l t i p l e t r a j ec t o r i e s tr ave l t h rough a con t ro
v o l u m e . T h i s p r o b l e m c a n b e e l i m i n a t e d b y n o t i n g th a t t h e
r a te , a t w h i c h o x i d i z e r i s s u p p l ie d t o e a c h c o n t r o l v o l u m e h a s t o
b e e q u a l o r g r e a t e r t h a n t h e r a te a t w h i c h o x i d i z e r i s c o n s u m e d
i n t h e s a m e c o n t r o l v o l u m e d u r i n g c o m b u s t io n . I n a g i v e n
c o n t r o l v o l u m e , o n c e t h e r a t e o f c o n s u m p t i o n o f o x i d i z e r
becomes g r ea t e r t han t he supp ly r a t e , combus t i on i s ha l t ed .
P a r t i c l e s t r a v e l i n g t h r o u g h t h e c o n t r o l v o l u m e s w i t h d e p l e t e d
ox id i ze r , w i l l no t co mbu s t .
Results
The t echn iq ue ou t l i ned a~bove i s i ncorpora t ed i n t o
F L U E N T 5 .4 C F D s o f t w a r e . C o a l c o m b u s t i o n a n d g a s i f ic a t io n
ins i de a t r anspor t gas i f i e r a r e used t o va l i da t e t he approach
presen t ed i n t h i s man usc r i p t . ; r he t r anspor t gas i f i e r ope r a t ed by
t h e E n e r g y & E n v i r o n m e n t a l R e s e a r c h C e n t e r a t t h e U n i v e r s it y
of No r t h Dakot a i s s e l ec t ed fo r t h i s purpose . The gas i f i e r i
used t o conver t coa l i n t o syn thes i s gas. F igure 1 shows t he
g e o m e t r y o f th e c o m b u s t o r / g a s if i e r u n i t. C h a r e n t er s t h e
m i x i n g z o n e a n d c o m b u s t w i t h t h e b u r n e r a ir , w h i c h e n t e rs t h e
mix in g zone on t he s ide . The un i t i s ope r a t ed a t sub-
s t o i c h io m e t r i c c o n d i t io n s w h i c h l e a d s t o b u r n i n g o f a s m a l
f r ac t i on o f t he cha r . I nc r eases i n t he gas t empera tu r e w i l l he l p
w i t h g a s i f ic a t i o n o f t h e r e m i n d e r o f t h e c h a r. C h a r m a s s
l o a d i n g w h i c h i s d e f m e d a s m a s s f l o w r a te o f c h a r t o m a s s f l o w
r a t e o f c h a r a n d b u r n e r a i r c o m b i n e d i s 0 . 8 8 . A s i t is s e e n in
f i g u r e 1 , tw o s e c o n d a r y a i r p o r t s a r e u s e d d o w n s t r e a m o f t h e
burn e r a i r en t ry t o a s s i s t w i t h cha r comb us t i on . F r esh
p u l v e r i z e d c o a l i s i n t r o d u c e d a t t h e u p p e r p o r t i o n o f th e m i x i n g
zone t o rep l en i sh t he cha r s tock . F igure 2 i ll us t ra t e s t he
l oca t i on o f c ros s s ec t i ona l p l anes wh ere t he t empera tu r e f i e lds
a r e r epor t ed . F igure 3 shows t he t empera tu r e f i e l ds a l ong t he
t r ave r se d i r ec t i on on p l ane s A t h rou gh F , ( r e f e r to f i gure 2 )
A l t h o u g h t h e m a j o r i t y o f t e m p e r a t u r e d a t a p o i n t s l a y a l o n g t h e
a v e r a g e t e m p e r a t u r e a t e a c h p l a n e , t h e p r e s e n c e o f s p u r io u s h o
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and co ld spot s on e ach p l ane c an be se en . F igu re 4 shows the
t empe ra tu re f i e ld a c ross t he same c ross se c t iona l p l ane s when
the tempe ra tu re l im i t e r i s u sed . The un rea l i s ti c ho t and co ld
spo t s o f f i gu re 3 a re e limina t ed . Wh en the ox id i z e r l im i t e r i s
a l so a c t iva t ed , t he t empe ra tu re f i e ld va r i ance on p l ane s A
th rough E becomes ev en le ss a s i t i s show n in f i gu re 5. A
compa r i son o f t he a c tua l t empe ra tu re va lue s w i th the th re e
s imu la t ions pe r fo rme d i s g iven by t ab l e 1 . W hen the concep t
o f t empe ra tu re and o x id i z e r l im i te r s a re u sed , t he t empe ra tu re
f i e ld is p red ic t ed more a ccu ra t e ly . As d i scussed e a r l ie r , a t h igh
so l id to ga s mass load ing , t he a ssumpt ion o f cons t an t ga s pha se
p rope r t i e s , ( cons t an t ga s s t e am t empe ra tu re and ox id i z e r mass
f ra c t ion ) l e ads to unphys i c a l t empe ra tu re pa t t ems . W hen the
the rma l mass o f pa r t i c le s i s no t g re a t , ( l ow pa r t i c l e mass
load ing ) , t he d i sc re t e pha se mode l c an p red ic t t he t empe ra tu re
f i e ld r e a sonab ly w e l l .
Conclusion
A m e thod o logy ha s been in t roduced to e limina t e
un rea l is i t c tempe ra tu re va lue s . The concep t o f t empe ra tu re and
ox id i z e r l im i te r s ha s succe ss fu l ly been imp lem en ted and t e s t ed .
A com pa r i son o f meas u red and s imu la t ed t empe ra tu re f i e ld s
ind ic a te s t ha t t empe ra tu re s a re p red ic t ed more a ccu ra t e ly when
the t empe ra tu re and ox id i z e r l im i t er s a re u sed .
Acknowledgments
T h i s w o r k h a s b e e n p e r f o r m e d u n d e r c o n t r a c t D E - A M 26
9 9 F T 4 0 5 7 5 f o r D e p a r t m e n t o f E n e r g y , N a t i o n a l E n e r g y
Techn o log y Labora to ry . The au tho rs wou ld l ike to t hank th
s t a f f o f F luen t W es t V i rg in i a o f f i c e i n pa r t icu l a r Dr . Mike
Pr inkey fo r a l l t he inva luab le d i scuss ions on fo rmu l i z ing th i s
app roach .
N O M E N C L A T U R E
A area
Cp spec i f i c hea t
h convec t ive hea t t r ans fe r coe f f i c i en t
m pa r t i c l e mass
m mass f l ow ra t e
S sou rce o r s ink t e rm
T Tempe ra tu re
t t ime
Subscripts
f f lu id
p par t ic le
L o c a t i o n
P lane D
N o l i m i te r W i t h t e m p e r a t u re W i t h t e m p e r a tu r e a n d M e a su r m e n t
(°k) l imi te r (°k) oxid izer l imi te rs (°k) (°k)
2000 1400 1310 1223
Tab le 1. A compa r i son o f s imu la t ed and a c tua l t empe ra tu re f i e ld in t he mix ing zone .
4
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Coal injection j _
Secondary
a ir in le t s ~ _ ~ ~gv Coa) in j ec t io n ~ / /
~ r ~ po r t ~ ~ / O utle t
Bum er air A v/ \ 1~'-
Figure 1. Com bustor/gasifiergeometry.
Mixing zone
Ciiiiiii~
plane F
plane E
plane D
plane C
plane B
plane A
Secondary air
inlets
~k
Figure 2.
Cross sectiona lplanes along he mixingzone w here temperaturevalu es are reported.
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3 0 0 0
2 5 0 0
•
2 0 0 0
•
1500
1000
500
u *
• 1 1
• I • : %
n ' ; , -
. . . ~ : ' .
- t ~
. . ~ •
• * ~ . ~ - - . . e ~ : ' r , . . : - b
. ' I t
-g
plane A
-0.05 0 0.05 0.1
Dis tance a lon g the t raverse di rect ion (m)
3 0 0 0
2 5 0 0
2 0 0 0
,~ 1500
E
1000
500
mm
ml
N
. g % , .
; . ; . % r - . r . ', r , . ~ . , ~ . . ~ . . . . .
• - ~ .
•
. ' '
plane C
, , , , I , , , , I , , , , I , , , ,
-0.05 0 0.05 0,1
Dis tance a lon g the t raverse di rect ion (m)
3 0 0 0
2 5 0 0
~ '
2 0 0 0 • •
E
lOOO . .
500
plane E
0 ' r ~ ~ I , , , , I r r i , [ r I , ,
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec t ion (m)
3 0 0 0
2 5 0 0
~ 2 o o o
•
1500
1000
500
u
• • m
o
ee
• o ° . ° ° ° t
. . . , 5 - : : : ; , - 5
° o w
e e
plane B
0 I i i i I I i i i I i r i r I i i i i
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec t i on (m)
3 0 0 0
2 5 0 0
, ~ . 2 o o o
~ 1 5 0 0
~ 1 0 0 0
500
, . . .
~ . . ~ . . ''w '~ 8 / • I . . .
plane D
t ~ i r I i i i r I T i i i I i i r I
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec ti on (m)
3 0 0 0
2 5 0 0
. ~ 2 0 0 0 - . .
ee
~ 1 0 0 0
%
500
plane F
0 , I r , , i l l r i r I r , r I
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec ti on (m)
F igure 3 .
Tem pera tu r e f i e l d a t c ros s s ec t i ona l p l anes A t h roug h E wi t ho u t t he t empera tu r e and ox id i ze r limi t er s .
6 Copyright (C) 2000 by ASME
8/9/2019 15089 Numerical Modeling of Combustion -Gasification
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3000 3000
2500
2000
~ 1 5 0 0
E l
l o o o
. . • ~ - ~
• v
# ~
• • • i i . i
500
plane A
0
i i ~ r I r i ~ i I i i ~ i I i i ~ i
-0.05 0 0.05 0.1
Distan ce along the traverse direction (m )
3000
2500
,~, 200 0
~d
1500
~.
~ - . , : .- ~ - - ~ ~ ' ¢ 4 % ' , .' d ' h ' . - , r % - . . , , . .
1000
500
plane C
0
~ i r r I i i , , I , ~ , , I ~ , ~ ~
-0.05 0 0.05 0.
Dis tance a long the t raverse direction (m)
2500
~,~2000
•
1500
~ 1 0 0 0
500
3000
. : - . -
plane B
r I r l I i i r 1 [ 1 i i 1 I i I I I
-0.05 0 0.05 0.1
Dis tance a long the t raverse direct ion (m)
2500
2000
5OO
~ 1 0 0 0
500
plane D
0 ~ r I , , , , I , r , r I ~ ~ , ,
-0.05 0 0.05 0.1
Dis tance a lon g the t raverse direct ion (m)
3000
2500
2
~ 1 5 0 0
. d . ~ . . m l ~ I l q l V l l t ql ~ , ~ l m l l l , m w l ~ , ~ 8 D *
1000
500
plane E
0 , , , , I , r , , I , , ,
I r ~ ~
-0.05 0 0.05 0.1
Dis tance a long the t raverse direct ion (m)
3000
2500
~ 2 0 0 0
E
•
1500
~ 1 0 0 0
500
plane F
0 ~ r r I ~ ~ I r ~ I ~ r
-0.05 0 0.05 0.1
Dis tance a long the t raverse direct ion (m)
F igure 4. Tempera ture f i e ld a t c ros s s ec t iona l p lanes A th roug h E wi th the t empera tu re l im i te r .
7 Copyright (C) 2000 by ASME
8/9/2019 15089 Numerical Modeling of Combustion -Gasification
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3 0 0 0 3 0 0 0
2 5 0 0
~ ' 2 0 0 0
1500
E
1000
•
500
plane A
0
I t I I I I I I I I I I 1 I I I I I I
lO105 0 0105 On1
Distance a lon g the t raverse di rect ion (m)
3 0 0 0
2 5 0 0
2 0 0 0
1500
E
1000
500
plane C
0
, I , , l , I l , i l I ~ l l l
-0.05 0 0.05 0.1
Dis tance a lo ng the t raverse di rect ion (m)
2 5 0 0
~,~ 20 00
E
~ 1 5 0 0
1000
500
plane B
0
I I I I I I I I I I I I I r l l I I I
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec t i on (m)
3 0 0 0
2 5 0 0
2 o o o
1 5 o o
1000
P h ~ r w . , u q ' ' q l Y ' l. , . l~ F ' . l ~ . . ~ Il i l , ,/ d u ~
5OO
plane D
0
l l l l I l i l i i i l l , i , l t l
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec ti on (m)
3 0 0 0
2 5 0 0
2 0 0 0
1500
1000
500
u ~ p m a u n d ~ ~ ~ l ~ a m ~ ( n l ~ i ~ m n m ~ p l N m m ~ m J l ~ l am a ml ~ m l ~ im m q m l I N •
plane E
, , , , I ~ r r , I , , , , I ~ , r r
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec t ion (m)
3 0 0 0
2 5 0 0
2 0 0 0
~ 1 5 0 0
gm,4w,O~l~ll~O~ , I~tl ,'ll p dmO~ilClFllm,llsm~,lwm,~bdm ~ e
~ 1 0 0 0
500
plane F
0 r r , I I r , ,
i i 1 , 1
l l , , , ,
-0.05 0 0.05 0.1
Di s t ance a l ong t he t r ave r se d i r ec ti on (m)
F igure 5 . Tem pera tu r e f i e l d a t c ros s s ec t i ona l p l anes A t h rough E wi t h t he tem pera tu r e and ox id i ze r l imi te r s .
8 Copyright (C) 2000 by ASME
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