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Show W in d t u r b u le n c e a n d e l e v a t e d fla r e fla m e s P. Gogolek and A.C.S. Hayden Advanced Combustion Technologies/CETC-O Natural Resources Canada A F R C S p r in g 2 0 0 4 u F la r e O p e r a tio n V a r ia b le s V a r ia b le s th a t a ffe c t fla re p e rfo rm a n c e : • F u e l f lo w ra te • F u e l c o m p o s itio n • W in d a n d w e a th e r • T ip d e s ig n • P ilo t • A s s is t m e d iu m a n d flo w ra te A F R C S p r in g 2 0 0 4 •V.rv » f ' K F lo w P a r a m e te r s Ratio of fuel momentum to wind momentum Ratio of fuel momentum to buoyancy of hot gases F r = A F R C S p r in g 2 0 0 4 - ; F lo w R e g im e M ap In(Fr) Jetting Wake Stabilized In(R) | Buoyant | A F R C S p r in g 2 0 0 4 - . R e g im e s -v- ^ 7 * f . S(V s / y/ Hr Elevated Flare R eacting Flow Mixing R e g im e s w a k e - d o m in a te d b u o y a n c y - d o m in a te d in e r tia -d o m in a te d t , «' V t s •<-A ?-'* R e g im e C h a n g e at a S in g le S ite A F R C S p r in g 2 0 0 4 X ' " A - D is tr ib u tio n o f W in d S p e e d C r u c ia l W in d P r o p e r t ie s W in d p r o p e r tie s im p o r ta n t fo r fla re s : • T u r b u le n t f lo w w ith u n ifo rm s h e a r s tr e s s • L o g v e lo c ity p ro file • T u r b u le n c e a n d p ro file d e te r m in e d b y te rra in (r o u g h n e s s ) • E d d ie s r a n g e fr o m > 1 0 m to < 0 .0 0 1 m m . A F R C S p r in g 2 0 0 4 •< -A ?-'* C r u c ia l F la r e P r o p e r t ie s F la rin g p r o p e r tie s im p o r ta n t fo r w in d : • M o m e n t u m flu x ra tio d e te r m in e s r e g im e • L e n g th s c a le s a re p ip e d ia m e te r a n d fla m e le n g th A F R C S p r in g 2 0 0 4 X ' " A - E x p e c t e d In te r a c tio n L a r g e s c a le t u r b u le n c e e x p e c te d to o n ly m o v e fla m e a ro u n d , n o t s ig n ific a n t im p a c t. S m a ll s c a le tu r b u le n c e (p ip e s iz e a n d le s s ) e x p e c t e d to in te r a c t w ith fla m e . A m o u n t o f tu r b u le n c e a t th is s c a le d e p e n d s o n te rr a in r o u g h n e s s , p ip e s iz e a n d h e ig h t a b o v e g ro u n d . A F R C S p r in g 2 0 0 4 In te n sity d e p e n d e n c e o n Intensity at pipe scale, - te r r a in R o u g h n e s s len g th , m VA'. G r id T u r b u l e n c e a n d W in d T u n n e l T e stin g ► Wind tunnel a llo w s s e q u e n c e o f ex p erim en ts to determ ine efficien cy and e m is s io n s . ► CANNOT reproduce ex actly th e full s e t o f wind properties. Grids can b e u s e d to in v estig a te s o m e o f the properties. A F R C S p r in g 2 0 0 4 X ' VA. Grid T urbulence Grid is a regular arrangem ent o f rods or bars. P r o d u c e s h o m o g e n o u s /is o tr o p ic tu rb ulen ce a s all w a k e s m erge. T urbulence intensity d e c a y s d ow n stream o f grid. Integral s c a le in c r e a s e s d ow n stream o f grid. A F R C S p r in g 2 0 0 4 - S / 2^ **v/ Grid T urbulence (continued) Log v elo city profile not reproduced ► N o t im p o rta n t fo r s tro n g w in d s b e c a u s e fla m e b e n d s Intensity can be m atched at flare pipe or flam e tip but not both sim u lta n e o u sly M o s t im p o r ta n t p r o c e s s e s a r e a t p ip e A F R C S p r in g 2 0 0 4 u vA V- FTF T urbulence R esu lts Grids form ed from ste e l sla ts. P ro d u ced intensity at pipe from 0.045 to 0.10. 2 lo ca tio n s d ow n stream T est c o n d itio n s: ► 4 " a n d 6 " p ip e s . N a tu ra l g a s ► E x it v e lo c it y f r o m 0 .2 to 1 .4 m /s A F R C S p r in g 2 0 0 4 S /2 ^ P r e lim in a r y C o r r e la tio n o f K In e ffic ie n c y • S tr o n g w in d s c a n c h a n g e fla r e r e g im e , d e c r e a s e e ffic ie n c y . • W in d tu r b u le n c e c a n b e s ig n ific a n t, e v e n a t le n g th s c a le s fo r fla re s . • G r i d t u r b u l e n c e c a n b e u s e d in w i n d tu n n e ls to re p lic a te im p o r ta n t fe a tu r e s o f w in d tu rb u le n c e . • T u r b u le n c e a n d w a k e s ta b iliz e d r e g im e c a n g iv e s ig n ific a n t in e ffic ie n c y A F R C S p r in g 2 0 0 4 |
