Available online a www.sciencedirec.com ScienceDirec Procedia Engineering 15 (016 ) 6 3 Inernaional Conference on Oil and Gas Engineering OGE-016 The analsis of ANSYS package applicabili for calculaing he elemens of he hea losses recuperaion ssem in he power uni of he mobile compressor uni Chernov G.I. a * asilev.k. a Balakin P.D. a Kalashnikov A.M. a a Omsk Sae Technical Universi 11 Mira Pr. 644050 Omsk Russian Federaion Absrac The aricle analses he issues of he calculaion echnique applicabili for he fuel heaing process in he channels of he elemens comprising he hea losses recuperaion ssem for he inernal combusion engines (ICE). The echnique on he basis of ANSYS package is presened. The echnique was used o calculae fuel heaing in he channels wih comple configuraion ha can be implemened in a hea losses recuperaion ssem in ICE. The comparison of he inegral compuaion resuls obained in he ANSYS environmen wih he calculaion resuls received b he sandard engineering echniques has shown heir saisfacor convergence. Also he resuls of calculaing he lengh of a kerosene heaing channel wih round and riangular cross secion are compared and analed. I is shown ha he heaing area in he channel wih round cross secion wih he heaing leading o he kerosene boiling is longer han in he channel wih riangular cross secion. 016 Published The Auhors. b Elsevier Published Ld. b This Elsevier is an open Ld. access aricle under he CC BY-NC-ND license (hp://creaivecommons.org/licenses/b-nc-nd/4.0/). Peer-review under responsibili of he Omsk Sae Technical Universi. Peer-review under responsibili of he Omsk Sae Technical Universi Kewords: heaing fuel; recuperaion of hea losses; ANSYS Nomenclaure ρ densi kg/m 3 ; componens of he vecor of he moving fluid paricle veloci on aes and ; Р he fluid pressure a an poin of he flow Pa; μ dnamic viscosi Pa s; * Corresponding auhor. Tel.: +7-381-6-9091. E-mail address: gi_chernov00@mail.ru 1877-7058 016 Published b Elsevier Ld. This is an open access aricle under he CC BY-NC-ND license (hp://creaivecommons.org/licenses/b-nc-nd/4.0/). Peer-review under responsibili of he Omsk Sae Technical Universi doi:10.1016/j.proeng.016.07.695
G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 7 λ hea conducion coefficien of he moving medium W/(m K); emperaure 0 С; с р hea capaci a consan pressure J/(kg К); f fluid emperaure near he wall surface; α he local hea ransfer coefficien W/(m K); n coordinae direced owards he liquid orhogonal o he surface; R gas consan for he given gas; compressibili coefficien; Q hea flow rae W. 1. Inroducion I is known ha almos all he energ supplied o he compressor is convered ino hea energ and hen i is ehaused ino he amosphere in he cooling ssems for gas lubricaing and cooling liquids and during pipe ransporaion of pressuran gas [1]. I is also known ha as a resul of fuel combusion in he working chamber more han half of he energ supplied o he power-uni (generall inernal combusion engine) is released ino he amosphere wih he ehaus gases in he cooling ssems for oil cooling liquid and charge air [3]. Effecive uiliaion of hese hea losses is a significan scienific and echnical problem. Soluions of his problem for he mobile compressor uni (MCU) are presened in works [45]. These publicaions presen hermodnamic analsis of various srucural diagrams of MCU hea losses recuperaion and provide he dependencies showing how he efficienc of he MCU wih he hea losses recuperaion ssem is affeced b he efficienc of he ssem's individual elemens. In paricular he impac of he inernal combusion engine (compressor drive) efficienc is shown. Obviousl he higher he efficienc of he inernal combusion engine (MCU drive) he higher he enire ssem's efficienc in general. There are several known was o improve he ICE efficienc [36]. The increased emperaure of he fuel supplied o he engine resuls in he increasing of he inernal combusion engine efficienc. The increase of he fuel emperaure before he injecion reduces is viscosi which in is urn leads o a beer aomiaion and complee fuel combusion [1789]. One of was o increase he fuel emperaure is o hea i in he channels of he fuel injecion nole casing [3] which is in conac wih he walls of he engine combusion chamber is emperaure reaching 800 K in gasoline engines and 1800 K in diesel ones [3]. In addiion he fuel can be a hea-bearing agen of he hea losses recuperaion ssem in MCU inernal combusion engines which suggess he need for developmen of he corresponding calculaion echniques.. Sud subjec The sud subjec is a clindrical wall wih an inernal cooling channel. This is a base for such sources of hea losses in inernal combusion engines as clinders noles and bearing unis. Kerosene is aken as a fuel since is hermal-phsical properies are similar o gasoline and diesel ones (Table 1 [6] parameers values are given a 0 С). Table1. Comparison of gasoline kerosene and diesel fuel properies in a liquid sae. Fuel Parameer Gasoline Kerosene Diesel fuel Densi kg/m 3 786 839 870 Hea conducion W/(m K) 0.17 0.119 0.118 Hea capaci J/(kg K) 1958 1886 1848 Surface ension N/m 0.033 0.08 0.03 Diffusion coefficien m /s 8.4 10-6 6.4 10-6 3.0 10-6
8 G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 The channel in he clindrical wall can be done as a wised loop wih a variable radius along he lengh of he winding as shown in Fig. 1. In addiion he spacing of he winding can also change. For problem simplificaion he sraigh channel was considered a he firs sage. Fig. 1. The diagram of he fuel heaing channel in he injecor nole casing. 3. Mehods The mahemaical model of iem including he main assumpions ssem of he main equaions and unambigui condiions are considered in work [6]. Fundamenal numerical echnique including he peculiariies of creaing a geomeric model a grid model gas (fluid) flow model and urbulence model boundar condiions as well as an eample of is implemenaion are considered in [6]. Furher we will consider some feaures of numerical mehods implemenaion. The known ssem of he equaions for convecive hea echange is used as a calculaion echnique for kerosene heaing in ANSYS environmen. The following assumpions are se as fundamenal. 1. The processes of fluid flow and hea echange are saionar. This assumpion is due o he fac ha he calculaion of he hdraulic processes is based on comple ssems of differenial equaions while he nonsaionari of he process leads o a sudden complicaion of he equaions ssem which hinders he preparaion of he soluion.. The emperaure of he wall heaing he moving sream remains consan. This assumpion follows from he firs one. 3. There are no inernal hea sources in he fluid flow. 4. he following equaions are used as he basic design ones in he analsis of he flow: The equaion of coninui epressing he mass conservaion law ρ ρ ρ 0 (1) where ρ is densi kg/m 3 and and are componens of he vecor of he moving fluid paricle veloci on aes and. Navier-Sokes equaion epressing he law of impulse variaion is used as he basis for disribuion of veloci profiles in he flow area: P 3
9 G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 () where Р is fluid pressure Pa; and μ is dnamic viscosi Pa s. All members of he equaions have he dimension of force per volume uni N/m 3. The energ equaion epressing he energ conservaion law forms he foundaion for disribuion of he emperaure field in he fluid flow area: (3) where Φ is dissipaion funcion epressing he energ dissipaion due o he absence of he viscous forces in he liquid:. (4) In he above given epressions λ is hea conducion coefficien of he moving medium W/(m K); is emperaure K; and с р is hea capaci a consan pressure J/(kg К). One can see from he energ equaion ha he emperaure field in a moving medium depends on he phsical properies of he medium and veloci fields. The hea ransfer equaion allowing he deerminaion of he local hea-ransfer coefficien α wih he help of a emperaure field () in a moving medium: (5) where w is emperaure of he heaing wall f is fluid emperaure near he wall surface α is local hea ransfer coefficien W/m K and n is coordinae direced owards he liquid orhogonal o he surface is calculaion saring from he heaing wall. 3 P 3 P Ф c p 3 Ф 0 ж ст n n w f
30 G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 Newon Richman equaion which allows deermining hea flow supplied o he moving medium from he heaing wall: dq w ст f ж df (6) where Q is hea flow rae W and F is he area of he heaing wall surface m. The above given equaions of coninui impulse variaion energ hea ransfer and Newon Richman equaion include hermophsical properies of he medium generall depending on emperaure: c p f. (7) In case of he moving medium being gas or vapor he densi dependence on emperaure is epressed via he equaion of sae which has he form of: P R ( 73) (8) where is compressibili coefficien and R is gas consan for he given gas. The equaions defining he dependence of he moving medium properies on emperaure are raher complicaed in an analical form herefore hese dependencies are given as ables which are enered in he librar of he subsances properies in special sofware packages such as ANSYS CFX. The above menioned equaions form a ssem which describes he heaing of a moving single-phase medium when he liquid or gas moves in he channel. The resuling differenial equaion ssem describes all possible cases of hea ransfer when flow moves in he channel. To find he onl possible soluion among numerous ohers he equaions ssem needs o be enhanced wih unambigui condiions which are divided ino he condiions of geomerical unambigui phsical unambigui and boundar condiions. The condiion of geomerical unambigui is ha he channel he flu moves in is a sraigh one wih wo pes of cross secion round and riangular wih an equilaeral riangle forming he basis of riangular cross-secion. In boh cases he cross-secional area was aken he same and equal o 176 mm. This corresponds o he channel diameer of 15 mm and he riangle side of 0. mm. The phsical condiion is seing he dependences of he moving medium (kerosene) properies on emperaure in he form of ables which are enered in he librar of he subsances properies in ANSYS CFX. The boundar condiions for hea ransfer calculaion is seing he emperaure of liquid kerosene a he channel enrance a he 0 C and also seing liquid kerosene veloci a he channel enrance as a se of values 0.1 0.5 and 1.0 m/s. Mass flow rae was aken as consan when calculaing he modes of liquid kerosene heaing boiling and kerosene vapors heaing. The boundar condiions include seing he emperaure of he channel side heaing wall as a se of several values changing wih he heaing flu mode. The pressure a he flow enrance in he channel was se arbiraril because he pressure changing along he heaing area is of ineres raher han he absolue pressure value. 4. Resuls and discussion The calculaion of he given equaions ssem wih he described unambigui condiions was made in ANSYS environmen wih he involvemen of he CFX applicaion. Consrucion of he channel models geomer was performed in he module Geomer; consrucion of he finie elemens compuaional grid was done in CFX Mesh; specificaion of he boundar condiions and calculaion parameers was performed in CFX Pre soluion was done in CFX Solve visualiaion and he analsis of resuls was carried ou in CFX Pos. The unis of all
G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 31 quaniies correspond o SI. The calculaion resuls are presened in Table an eample of calculaion resuls for a paricular case (a kerosene rae =0.5 m/s and a wall emperaure w =000 С) is given in Fig. 3 and 4. Fig.. The change of he flow emperaure along he channel a a kerosene veloci of 0.5 m/s and he wall emperaure w=000с: line 1 is he channel wih circular cross-secion and line is he channel wih riangular cross secion. Fig. 3. Temperaure disribuion in a longiudinal plane passing hrough he smmer ais of circular cross-secion (=0.5 m/s w=000с). Fig. 4. Temperaure disribuion in a longiudinal plane passing hrough he smmer ais of riangular cross-secion (=0.5 m/s TW=000С). Table. The dependence of he lengh of liquid kerosene heaing area on he emperaure of he heaing wall and he flow veloci. Temperaure of he heaing wall Т С eloci m/s Round cross-secion Channel lengh L mm Triangular cross-secion 0.1 783 550 500 0.5 05 1711 1.0 780 317
3 G.I. Chernov e al. / Procedia Engineering 15 ( 016 ) 6 3 0.1 350 196 1000 1500 000 0.5 991 735 1.0 160 1013 0.1 4 108 0.5 640 471 1.0 80 661 0.1 165 69 0.5 474 319 1.0 610 456 5. Conclusion The inegral calculaion resuls from he ANSYS medium were compared wih he calculaion resuls based on he sandard engineering echniques [10] wha demonsraed heir saisfacor convergence. Furhermore he analsis of he calculaions shows ha he lengh of he heaing area leading o he beginning of he kerosene boiling in he channel wih round cross secion is larger han ha in he channel wih riangular cross secion. This is due o he large perimeer of riangular cross-secion. The increase in flow veloci leads o he increase in he lengh of he heaing area which is a qualiaive verificaion of he calculaion resuls. All his proves ha he presened echniques developed on he basis of ANSYS package are applicable for he calculaion of fuel heaing in he channels wih comple configuraion ha can be used in hea losses recuperaion ssem in inernal combusion engines. References [1] A.M. Arkharov e al. Thermal echnolog Moscow N. E. Bauman MGTU publishing house 004. 71 p. (in Russian) [].L Yusha Cooling ssem and gas disribuion of volume compressors. Novosibirsk: Science 006. 36 p.(in Russian) [3].N. Lukanin e al. Inernal combusion engines: heor of working processes "Higher school" 007. 479 p. (in Russian) [4].L Yusha G.Chernov Effeciveness analsis of using he Rankine ccle and ccle of refrigeraion machine for recuperaion of hea losses in mobile compressor unie 8h Inernaional Conference on Compressors and Coolans. Papiernička Slovakia 013 45 p. [5].L. Yusha G.I. Chernov Thermodnamic analsis of efficienc of compressor unis wih recuperaion of hea losses monograph Omsk: Publishing house OmSTU 014 104 p. (in Russian) [6] R.Z. Kavarade Theor of pison engines. Special chapers: he ebook for higher educaion insiuions in "Inernal combusion engines" for sud program "Power plan engineering" Moscow N.E. Bauman MSTU publishing house 008 70 p. (in Russian) [7].A. Markov S.N. Devanin.I. Malchuk Injecion and fuel spreading in diesels Moscow N.E. Bauman MSTU publishing house 007 360 p. (in Russian) [8] J.C. Den Basis for he comparison of various eperimenal mehods for sud spra peneraion SAE paper 710571 1971 18 p. [9] H. Hirosu M. Arai Srucures of fuel spra in diesel engines peneraion SAE paper 900475 1990 14 p. [10].A. Grigoriev Y.I. Krokhin. Hea and mass ransfer devices of crogenic equipmen Moscow Energoida 198 31 p. (in Russian)