Parametric Consideration of Marine Diesel Engine Output for Maximum Operation

Transcription

1 Intenational Jounal of Engineeing and echnology Volume No., ach, aametic Consideation of aine Diesel Engine Outut fo aximum Oeation Anthony, A. Ishiodu, Ezenwa A. Ogbonnaya Deatment of aine Engineeing, aitime Academy of Nigeia, Oon, Akwa Ibom State, Nigeia Deatment of echanical Engineeing, ichael Okaa Uniesity of Agicultue, Umudike, Umuahia, Abia State, Nigeia ABSRAC Diesel engines simulation has contibuted immensely towads the aim of new ealuation and deeloment. his esent wok contibutes to a bette simulation of the tansient oeation of imoing the existing elation. It deals with the aametic consideation of aine Diesel Engine (DE) outut fo maximum oeation. A fou stoke cateilla 6B seies DE with 6 VS was used to actualize the wok. A well-known model was adoted using temeatue aoach to obtain efficiencies of the engine. A comute ogam code named DEAC witten in isual-basic ogamming language was deeloed. he esult obtained affimed that the alue of.9kw to 67.8KW of owe outut and 9.kN/m to 79.kN/m fo mean effectie essue should be maintained to aoid any beakdown of the engine. Keywods: aametic consideation, maine diesel engine, outut and maximum oeation NOENCLAURE N Reolution of the engine, m K Constant L Stoke of engine, m A Aea of the cylinde, m Comession atio V s Swet olume, m m ean effectie essue, kn/m W owe outut of the engine, KW Comession temeatue at stage, o C Initial comession temeatue at stage, o C Comession essue at stage, kn/m Comession essue at stage, kn/m c Cut off atio emeatue at stage, o C emeatue at stage, o C emeatue at stage, o C C Constant olume comession m ass flow ate, Kg/s C Secific heat caacity, KJ/kg η i Indicated themal efficiency, % E Effectie owe, KW b Bake owe, KW η b Bake themal efficiency, % Isentoic comession atio BDC Bottom Dead Cente DCo Dead Cente I. INRODUCION Comession Ignition Engines (CIEs) of diesel engines (DEs) as they ae commonly known afte thei inento D. Rudolh Diesel, conet chemical enegy stoed in fuel into mechanical wok at the cank shaft eolution. Whilst these engines come in aiety of diffeent foms and astly diffeent sizes they ae ely on the incile that fuel is ignited by heat geneated duing comession in the cylinde []. Howee, thei oeation is geneally based uon eithe the two o fou-stoke engine cycles, which efe to the numbe of iston stokes occuing duing one cycle of eent [, ]. he maine diesel engine (DE) is a ey comlicated and ugged mechanical system due to the existence of the tubo chage and all the othe sub-systems. hese engines offe aious adantages among which ae high efficiency, high owe concentation and long oeational life time []. On the othe hand, thei lage size can cause ISSN: 9- IJE ublications UK. All ights eseed. 9

2 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, geat difficulties in the diagnoses of imoe oeation. he aametes usually measued ae aious temeatues, ibation leel, shaft seed, owe outut, flow ate and aious essue. Een afte these data ae in hand, it is extemely difficult in many cases, to identify the causes of the faults, since most of these aametes may hae simila effects []. As a tyical DE, thee ae howee, fundamental mechanical and themodynamic diffeences between them and othe cycles which make comession less aluable than might be exected. In the theoetical cycle, thee is no chemical change in the woking fluid which is assumed to be ai, and the exchanges in the cycle ae made extenally to the woking fluid. In the actical cycle, the heat suly as obtained fom the combustion oducts must be exhausted fom the cylinde befoe a fesh chage ai can be induced fo the next cycle [6, 7]. he actical cycle also consists of the exhaust and induction ocesses togethe with the comession and exansion ocess as in the theoetical cycle [8]. Othe Aoaches Ishiodu and Ogbonnaya [] dafted a wok on otimizing the efomance of a DE towads oactie condition monitoing. In the wok, a comute ogam named DEEA witten in V-Basic ogamming Language was used to actualize thei wok. Futhemoe, Rahim [9], oduced a wok on efomance of an ieesible Diesel cycle unde aiable stoke length and comession atio. In that wok, the elations between the owe outut and the themal efficiency ae deied in detail. Subsequently, the maximum owe outut and the coesonding efficiency limits of the cycle with consideations of heat tansfe and fiction like tem losses ae also found with clea detailed numeical examles. Rao, [] caied out exeimental inestigations on the influence of biodiesel on efomance, combustion and emission chaacteistics of a Diect injection and CIE. In the wok, the exeiments wee efomed at diffeent engine oeating egimes with the injection timing escibed by the engine manufactues fo diesel fuel. he engine chaacteistics with Jatoha biodiesel wee comaed against those obtained using diesel fuel. A eseach on numeical simulation fo aametic study of a two stoke comession ignition diect injection linea engine was executed by Ehab []. In that wok, the simulating ogam adoted used a seies of dynamic and themodynamic equations that wee soled simultaneously to edict the efomance and analyzed the diffeent factos affecting the oeation of the twostoke CIE couled with line altenato. Aoach used in this esent wok he esent wok contibutes to a bette simulation of the tansient oeation by imoing on the existing elations. It deals with aametic consideation of D E outut fo maximum oeation. his was bought to fuition using a softwae named DEAC witing in isual basic (V- Basic) ogamming language. DEAC stands fo aine Diesel Engine aametic Analysis and Consideation. his was caied out with a case study of a cateilla 6 VS engine seies 6B, with 7mm boe/9mm stoke of aoximately 9KW owe outut.. AERIALS AND EHODS Stictly seaking, aametic analysis inoles the detemination of ange of aiations in a hysical oeties o themodynamic oeties of a gien system whose behaiou has been studied only exeimentally. Cateilla 66B DE is a high seed engine with tunk configuation. he engine oeates on fou stoke cycle and has a comession atio of to. It has a 7mm boe/9mm stoke with a maximum seed of 6 m. Othe featues includes V6-cylinde aangements and the highe B-atings, can offe outut u to aound KW by its counte clockwise otation facing the fly wheel []. he theoetical analysis fo the ealuation of a -stoke cateilla 6B seies DE aametic efomance was caied out using the ai standad dual cycle as shown in figue (). Figue shows a - diagam, which is a theoetical analysis of dual combustion cycle. ISSN: 9- IJE ublications UK. All ights eseed. 96

3 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, ISSN: 9- IJE ublications UK. All ights eseed. 97 Fig : Dual Cycle.V diagam fo full load oeation of model engine [6, 7] In this cycle, the heat addition occus duing the constant olume ocess, Hence ( ) ( ) c c Q + he heat ejection takes lace duing the constant olume ocess so that; ( ) Q c he wok outut is theefoe ( ) Q - Q with the esult that the themal efficiency of the cycle may be exessed as; + c c c c c m - Q Q η + - In ode to exess the aboe equation in tems of engine aametes, we shall exess all temeatues in tems of, theefoe Fou ocess in figue and b. but, - - Fom ocess, 6 So that V sincev, A new engine aamete, the essue atio is defined as such that - 7 Fo ocess, so 8 but - c c so and 9 Fo ocess -, so that Since the ocess being isentoic, then Cleaance Volume C BDC Swet Volume DC V

4 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, c c c Substituting all temeatue alues into the equation fo the themal efficiency of the dual cycle yields η m - - ( ) c ( ) ( c ) + ( c ) - [( ) + ( c ) ] ( c ) - [( ) + ( ) ] - Equation is the exession fo the themal efficiency of the mixed o dual cycle. It is obtained using aametic analysis. Othe engine efomance aametes ae; Fo comession atio Swet olume s Net owe outut whee c - 6 W m x m mean effectie essue s swet olume As ealie stated in Ishiodu and Ogbonnaya, the owe outut can be detemine as s whee L ANks Vs 6 L stoke of the engine A Aea of the boe N Reolution of the engine (m) k constant fo stoke engine and ½ fo fou stoke engine hen swet olume, Vs becomes L ANks N Vs k A ks x 6 6 Bake themal efficiency whee b E Bake owe Effectie owe b μ 8 b E Figue is the flow chat fo DEAC. he flow chat was used to wite a double loo iteatie -Basic comute ogam. he ogam heled to calculate the aametic asects of the efeenced engine which includes all the themodynamic oeties of an engine, such as wok outut and E at aious oeating seed of the engine.. RESULS AND DISCUSSION he theoetical esult obtained at aious themodynamic oeties of the efeenced engine is esented in table (). he themodynamic oety of inteests ae temeatue essue and olume at stategic oint shown in figue (a) and (b). Othe engine efomance aamete which includes comession atio, swet olume and owe at aious seeds is also shown in the table. W m L AN ks 7 So that ISSN: 9- IJE ublications UK. All ights eseed. 98

5 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, Stat Figue shows the aiation in the highe temeatue at the constant olume located at oint. In the figue, it is found that inceases with the incease of comession atio. L7 S6 K. INU AREA, A I emeatue at oint 6 Comession Ratio INU SEED N(I) INU WORK W(I) Fig : lot of temeatue against comession atio Figue shows the lot of comession atio against owe outut. Fom the gah, it can be seen that the owe outut esus comession atio is aoximately aabolic like cues. In othe wod, the owe outut inceases with a esultant incease in comession atio. II+ Is I Yes I No RIN (I), W(I) I< Is I Sto No Fig. : Flow chat fo DEAC hese esults in tabula foms wee used to show the alues at diffeent oint of the ai standad dual (mixed) cycle used fo the ealuation of the combustion ocess of the engine. Yes Fig : owe outut against comession atio Figues and 6 shows the elation between owe outut against mechanical and Bake themal efficiency esectiely. In the lots the damatic incease in efficiency e unit incease in owe outut is demonstated. owe outut KW echanical Efficiency Fig. : owe outut against mechanical efficiency ISSN: 9- IJE ublications UK. All ights eseed. 99

6 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, echanical, bake and indicated themal efficiency ec.eff B.eff Indi.eff Seed, m Fig. 8: Gah of mechanical, bake and Indicated themal efficiencies against seed Fig. 6: owe outut against efficiency Figue 7 shows the gah of owe outut against seed fo all the oeational conditions of the engine unde inestigation anging fom 7 m to 6 m. Oiginal tial alues of owe with elation to seed fom the manufactue wee dawn on the same gah in ode to comae it with the calculated alues obtained duing the engine ealuation and analysis. Efficiencies Seed m Fig. 7: Efficiency against seed Oi owe cal. Kw he elation between the diffeent efficiencies at aious seed of the engine unde inestigation is clealy shown in figue 8. Fom the gahs, it is eident that the diision of bake owe by the indicated owe would gie the mechanical efficiency which is a clea indication that the best efomance of the engine occu at the designed seed of 6 m. Figue 9 shows the aiation of seed of the engine unde inestigation at a gien inteal. Fom the gah, it is shown that the engine tends to incease as the oeational time of the engine inceases. Soeed, m Fig. 9: Gah of seed against time. CONCLUSION ime, h A wok has been caied out on aametic consideation of DE outut fo maximum oeation. It is obseed that the comession atio lays a majo ole in the calculation of essue, temeatue and olume of the engine in conjunction with the initial intake alues of the temeatue and boost essue gauge eadings. o detemine the damatic incease of engine efomance, a well-known mathematical model was adoted using a temeatue aoach to deie the mechanical efficiency of the engine. A cateilla 6VS ISSN: 9- IJE ublications UK. All ights eseed.

7 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, engine seies 6B engine with 7mm boe/9mm stoke of aoximately 9KW owe outut was used as the test engine. Simulation was also caied out using a softwae name DEAC witing in V-Basic ogamming language. REFERENCES [] Ogbonnaya, E.A., 998. Condition onitoing of a Diesel Engine fo Electicity,.ech, hesis Deatment of aine Engineeing, RSUS ot Hacout... [] Douglas, E.., 7. onitoing of the iston Ring ack and Cylinde Linea Inteface in Diesel Engines hough Acoustic Emission easuements. h.d hesis, Deatment of echanical Engineeing, School of Engineeing and hysical Sciences, Haiot Watt Uniesity. 8. [] Ogbonnaya E. A, Simulation of Diesel Engine Seed Related chaacteistics. he Nigeia Institution of echanical Engines, A Diision of the Nigeian Society of Enginees oceeding of the d annual geneal intenational confeence, nd Octobe,, [] Ishiodu, A.A., 8. Ealuation and Analysis of the efomance of aine Diesel Engine. a Case Study of Cateilla Engine 6B Seies. -ech hesis, Deatment of echanical Engineeing, Ries State Uniesity of Science and echnology. (RSUS) Nkolu Oowoukwo, ot Hacout.. [] Ishiodu, A.A and E.A. Ogbonnaya,. Otimizing the efomance of a aine Diesel Engine owad oactie Condition onitoing. Jounal of Emeging end in Engineeing and Alied Sciences (JEEAS) (): 8 8 (c) schola link eseach institute jounals, 8 8. [6] Oteh, U., 6. Engineeing themodynamic, inted in the United States of Ameica Bloomington, Indiana 9. [7] Easto,.D., and A. cconkey,. Alied hemodynamics fo Engineeing echnologist, eason Education Singaoe te, Ltd, 6. [8] Boy,. and. Behens, 9. aine Diesel Engine edited in Comendium aine Engineeing, DW edia Gou Gmbli Secliaen Velag ost box 69. D- Hambug. 7. [9] Rahim, E.. efomance of an Ieesible Diesel Cycle Unde Vaiable Length and Comession Ratio. Jounal of Ameican Science, asland ess. 8-6 aailable at htt:// [] Rao,.V.,. Exeimental Inestigation on the Influence of oeties of Jatoha Biodiesel on efomance, Combustion, and Emission Chaacteistics of a Di Ci Engine, Jounal Wold Academy of Science, Engineeing and echnology 7, [] Ehab, F.S, Numeical Simulation fo aametic Study of a wo-stoke Comession Ignition Diect Injection Linea Engine, hd Dissetation Deatment of echanical and Aeosace Engineeing, College of Engineeing and ineal Resouces, West Viginia Uniesity,. ISSN: 9- IJE ublications UK. All ights eseed.

8 Intenational Jounal of Engineeing and echnology (IJE) Volume No., ach, able : Diffeent Values obtained fo the ai standad dual (mixed) cycle fo the engine at all oeating conditions essue (ba) Volume (m /s) emeat ue (K) Comessio n Ratio ( ) V V V V V Swet Volume (m /s) owe Inut KW Seed (m) Oiginal owe kw Calculated owe kw ec hanic al effici ency Engine efficiencies Indicated themal efficiency Bake themal efficiency ISSN: 9- IJE ublications UK. All ights eseed.