OPTIMIZATION OF A NONCONVENTIONAL ENGINE EVAPORATOR

Transcription

1 Jornal of KONES Powerran and Transpor, Vol. 17, No. 010 OPTIMIZATION OF A NONCONVENTIONAL ENGINE EVAPORATOR Andre Kovalí, Eml Toporcer Unversy of Žlna, Facly of Mechancal Engneerng Deparmen of Aomove Technology Unverzná 815/1, Žlna, Slovaa el.: , , fa: e-mal: andre.ovalc@fsro.nza.s, eml.oporcer@fsro.nza.s Absrac The papers deal wh he opmzaon of he evaporaor of a nonconvenonal combson engne. Lhm bromde lqd (LBr - an alernave coolng medm) flows n a coolng crc of a nonconvenonal energec n. The solved energec sysem s defned n he area of rgeneraon sysems. The menoned sysem s a sorce of elecrc energy, cold and hea oo. The space geomercal model correspondng o he geomery of he orgnal evaporaor s creaed n he CAD (Comper Aded Desgn) sofware CATIA. Only one half of he evaporaor s creaed becase of he decrease n he demand on he compaonal means. Ths CAD model s hen mpored no he preprocessor Gamb. The mpored model s repared and a sable mesh s hen creaed. The las sep s he defnon of he ypes of bondary condons. The compleed compaonal mesh s hen epored from Gamb and mpored no he CFD (Compaonal Fld Dynamcs) sofware Flen. Flen s sed for he nmercal smlaon of he coolng medm flow n an evaporaor. The smlaon shows he fllng of he evaporaor cone, he me when he coolng medm sars o por hrogh he edge of he evaporaor cone, he fllng of he evaporaor rng and fnally also he fac ha he off-ae s able o ae away he needed amon of coolng lqd from he evaporaor. Keywords: nonconvenonal engne, evaporaor, nmercal smlaon, mesh, flow 1. Inrodcon A nonconvenonal combson engne s one par of a nonconvenonal energec sysem prodcng elecrc energy, hea and cold. I s a specal ype of a combned hea and power n. The engne coolan s replaced by he mre of he lhm bromd lqd wh waer. The engne sed n he sysem s for sroe compresson gnon engne Z8004 wh raed power of 77 W a 00 mn -1. The am of he nmercal smlaon s o acqre nformaon regardng he dmensons and parameers of he evaporaor sed n he menoned energec sysem. The lhm bromd lqd flow n he evaporaor s smlaed.. Evaporaor desgn and parameers The CAD sofware sed for he model creaon s CATIA V5. The model of he whole evaporaor can be seen n he Fg. 1. For he smlaon was sed only one half of hs space becase of he symmery of he geomery wha allows o decrees n he reqremens on he sed hardware and compaonal me. The nner bgger dameer of he evaporaor cone has he vale of 93.5 mm and he smaller one he vale of 43.5 mm. The hegh of he evaporaor cone s 300 mm. The nner dameer of he boom ole ppe s 36 mm and he dameer of he op ole ppe s 4 mm. The nner dameer of he nle ppe s 43.5 mm.

2 A. Kovalí, E. Toporcer 3. Lhm bromd lqd flow smlaon Fg. 1. CAD model of he evaporaor The creaed model was epored from CATIA as sep fle and hen mpored no he GAMBIT, whch s sed as a preprocessor for he Flen. In he GAMBIT he ypes of bondary condons were se o he specfc srfaces. The ype of medm was se o fld. Ne sep n he GAMBIT was mesh generaon. The ype of compaonal elemens was erahedral cells. The reslng mesh consss of cells. The mpored mesh no he Flen wh he specfc ypes of bondary condons (yellow symmery, blac wall, ble velocy nle, red pressre ole) can be seen n Fg.. Fg.. Compaonal mesh wh he specfc ypes of bondary condons 18

3 Opmzaon of a Nonconvenonal Engne Evaporaor Fgre 3 shows he deal of he mesh n he area of he boom ole. Ne sep was he defnon of he compaonal model. Vales for he bondary condons were se. The RNG - rblen model was sed for he flow smlaon. Ths model s enogh robs and sable for he solon of rblen flows and hea ransfer. The renormalzed procedre consss of a gradal elmnaon of small rblences. Eqaon of moon s ransformed so ha rblen vscosy, forces and nonlnear members are modfed. Assmng ha he rblences are relaed o dsspaon, hen, he rblen vscosy depends on a degree of rblences and he RNG mehod consrcs hs vscosy wh he help of erave elmnaon of narrow bands of wave nmbers. The followng eqaon s sed for he erave process: 3 l l A dl d l. (1) The RNG model derved by a sascal mehod, averaged, s formally of he same form as he classcal model. The eqaon for he ransfer of moon s n he form: F g p 3 () and, sbseqenly, ranspor eqaons are sed: S, (3) R C S C 1. (4) Tme sep was se o s. The velocy n he nle was se o 0.56 m s -1. Fg. 3. Deal of he mesh n he area of he boom ole 19

4 A. Kovalí, E. Toporcer Fgre 4 and 5 show he fllng of he evaporaor cone n he me of 0.1 s and 4 s. Fg. 4. Coolan level n he me of 0.1 s Fg. 5. Coolan level n he me of 4 s 0

5 Opmzaon of a Nonconvenonal Engne Evaporaor From he Fg. 6 can be seen ha he lhm bromd lqd sars o por hrogh he edge of he evaporaor cone n he me of abo 10 s afer he sarng of he calclaon. Fg. 6. Coolan pors hrogh he edge of he evaporaor cone n he me of 10 s Fgre 7 shows he fllng of he evaporaor rng afer he coolan pored from he cone. Fg. 7. Fllng he evaporaor rng n he me of 11 s 1

6 A. Kovalí, E. Toporcer In he Fg. 8 and 9 can be seen he off-ae capably o ae away all needed amon of coolan from he evaporaor. Fg. 8. Flow n he evaporaor n he me of 1 s Fg. 9. LBr volme fracon dsrbon n he me of 15 s

7 Opmzaon of a Nonconvenonal Engne Evaporaor Fgre 10 shows he rblen nensy dsrbon n he me of 15 s. 4. Conclson Fg. 10. Trblen nensy n he me of 15 s The smlaon shows ha he coolng lqd sars o por hrogh he edge of he evaporaor cone n he me of abo 10 s afer he sarng of he calclaon. Oher nformaon ganed from he smlaon s ha he off-ae shold be able o ae away all needed amon of coolan from he evaporaor. Acnowledgemens Ths conrbon was creaed whn he framewor of he proec SK-PL (SK-PL /807/010), whch s sppored by he Agency for Sppor of Scence and Technology of he Slova repblc and he proec VEGA 1/0554/10, whch s sppored by he Mnsry of Edcaon of he Slova repblc. References [1] Hlava, V., Kovalí, A., Toporcer, E., Modelng of flow n an evaporaor of a nonconvenonal combson engne, In Combson Engnes - Sln Spalnowe, No 009-SC1, 009. [] Labda, R., Isení, R., Hlava, V., How o nflence CO prodcon by syle of vehcle conrol, New Trends n Consrcon and Eploaon Aomobles, Vehcles 007, SPU Nra, Nra 007. [3] Mr, A., Szlacha, Z., Cse, J., Efey zasosowana ceramczne powo na den oa slna wysooprnego, IV Sympozm Naowo-Technczne Sln spalnowe w zasosowanach wosowych, Jraa [4] SK-PL , (SK-PL /807/010). [5] VEGA 1/0554/10. 3