An Analytical Investigation of Diesel Engine Performance using Biodiesel and Preheated Jatropha Oil Said. M. A. Ibrahim a, K. A. Abed b, M. S.

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1 International Journal of Engineering & Technology IJET-IJENS Vol:14 No:06 6 An Analytical Investigation of Diesel Engine Perforance using Bioiesel an Preheate Jatropha Oil Sai. M. A. Ibrahi a, K. A. Abe b, M. S. Ga c a Departent of Mechanical Engineering, Faculty of Engineering, Al Azhar University, Nasr City,Egypt. b,c Departent of Mechanical Engineering, National Research Centre c Corresponing Author Eail: ga7@yahoo.co Abstract-- In this work, a single zone copression ignition engine cycle oel is use to preict the cycle perforance of a iesel engine for the cases of using iesel fuel blens of 0, 40, 70, 100 %, unheate jatropha oil () an preheate jatropha oil at a teperature of 90 C (). The apparent fuel burning rate coul be expresse as the su of two coponents, one relating to preixe an the other to iffusion burning. A coputer coe for the cycle oel has been prepare by MATLAB progra to perfor nuerical calculations. The effect of loa variation on peak cyliner pressure, specific fuel consuption an theral efficiency is analyze. An experiental investigation has been carrie out on a iesel engine fuelle with,,, an iesel fuels. The relative error of cyliner pressure between theoretical an experiental ata for iesel fuel,,, an is less than about 4, 5, 1, 4 an 4%, respectively. It was observe that there is a goo agreeent between siulate an experiental results, these results inicate that the assuptions of the oel are reasonable. Inex Ter-- Jatropha oil, Bioiesel, Specific fuel consuption, Theral efficiency, Siulation. I.INTRODUCTION Coputer oels of engine processes are valuable tools for analyzing engine perforance, exhaust eissions preiction an allow exploration of any engine esign alternatives in an inexpensive fashion Diesel engine siulation oels can be classifie into three categories, zero iensional, single zone oels, quasi iensional, ulti zone oels an ultiiensional oels [1]. Quasi iensional oels cobine soe of the avantages of zero iensional oels an ulti iensional oels. They solve ass, energy equations, but o not explicitly solve the oentu equation. These oels can provie the spatial inforation require to preict eission proucts an require significantly less coputing resources copare to ulti iensional oels. Quasi iensional cobustion oeling coul be consiere an active area of research []. A quasi iensional two zone theroynaic oel is use to stuy perforance characteristics of jatropha bioiesel engine. Using this oel, pressure, teperature an other require properties are copute nuerically. In this paper, the effect of loa variation on specific fuel consuption an theral efficiency is analyze. The oel has been valiate by an experiental analysis. The siulation oel has been use to investigate the perforance of iesel engine fuele by biofuels. The nuerical siulation was perfore at constant spee. The perforance paraeters such as cyliner pressure, specific fuel consuption an theral efficiency were stuie an copare with iesel fuel [3]. II. MODEL DESCRIPTION AND FORMULATION Single zone theroynaic oel is chosen to siulate four stroke cycles (intake, copression, expansion, an exhaust) of copression ignition engine fuelle with various types of alternative fuels such as iesel, bioiesel an their blens. This oel preicts engine perforance paraeters. The cobustion oel was chosen to give a reasonable accuracy with fast coputation. The unburne ixture for copression ignition engine uring intake an copression strokes consists of air, an previously burne gases. The coposition of the unburne ixture oes not change significantly uring intake an copression strokes. It is sufficiently accurate to assue the coposition is frozen [3]. The cobustion proucts or burne ixture gases are close to theroynaic equilibriu uring the cobustion process an uch of the expansion process. In this oel, the cyliner charge is assue to be unifor in both teperature an coposition. The burne gases are consiere to be in cheical equilibriu whereas the unburne gases are assue to be frozen. The first law of theroynaics, equation of state, conservation of ass an volue are applie to the unburne an burne gases. A syste of first orer orinary ifferential equations can be obtaine for the pressure, ass, volue an teperature of the unburne an burne gases. The first law of theroynaics is use to calculate the pressure, heat release rate an the ass fraction of burne gases as a function of crank angle. The heat aition for copression ignition engine ay be a function of crank angle [, 3, 4].

2 International Journal of Engineering & Technology IJET-IJENS Vol:14 No:06 7 The apparent fuel burning rate coul be expresse as the su of two coponents, one relating to preixe an the other to iffusion burning. Aong these oels, the preicting results with Watson oel agree best with the experiental ata, so Watson oel is selecte. Watson oel consists of two functions which are superipose. The first function siulates the preixe cobustion an the secon siulates the iffusion cobustion. A weighting factor β is use to eterine how uch ephasis is given to each of the functions as shown in the following equations []. b X p (1) b b( ) X p X () p p ( 1 (3) b ) 1 (1 K1 ) K (4) K4 1 exp( K ) (5) b en ign 3 (6) K p ID 0.35 (7) *10 ( ID* N) (8) K 5000 (9) K (10) K K (11) = ass of fuel - air ixture in kg, b = fuel ass burne in kg, p = fuel ass burne in preixe phase in kg, = fuel ass burne in iffusion phase in kg, β = Weighting factor, Φ= Fuel air equivalence ratio, ID= Ignition elay in illi secon, N = Engine spee in rp, K 1,K,K 3 an K 4 = shape factors for preixe an iffusion burning phases, θ ign = start angle of heat release (cobustion start angle), Δθ= the uration of heat release (cobustion uration fro X b =0 to X b =1) is given by100 Crank Angle as a atu value which nees to be large enough to copletecobustion an X b = ass fraction burne. In the present oel, the engine fuelle with soe fuels such as iesel, bioiesel, ixture of iesel an bioiesel. The olecular forula use for iesel is taken as C 10 H 0, whereas for jatropha bioiesel, it is taken as C 18 H 34 O. A. Heat Transfer Heat transfer has becoe inevitable in any internal cobustion engine so as to aintain cyliner walls, cyliner heas an pistons secure in service teperatures. Heat is transferre fro or to the working flui uring every part of each cycle. The priary heat transfer fro the cyliner gases to the wall is ainly by convection, an only 5% by raiation. The heat transfer is given by the following equation [5, 6]. Q ht 4 w 4 ha( T T ) ( T T ) (1) Q ht the heat transfer in Watt, = w h= the heat transfer coefficient in W/.K, A = the cobustion chaber surface area in, T w = the wall teperature in K, ε= eissivity (ε =0.69 W/.K 4 ) an ζ = Stefan Boltzan constant =5.67x10^-8 W/.K 4. The epirical relation for heat transfer coefficient is shown VTr 0.8 h( ) 3.6( b )( P )( T )(( C1u p C( )( P P )) ) (13) PV r r

3 International Journal of Engineering & Technology IJET-IJENS Vol:14 No:06 8 b= the cyliner bore in, P= the cyliner pressure in at, T= the cyliner teperature in Kelvin, V = the isplaceent volue in 3, P = the otoring pressure in at, u p = u = ean piston spee in /sec, the average cyliner gas velocity in /sec, r = engine copression ratio, P at = the atospheric pressure (P at =1 at), C 1, C = are constants, copression (C 1 =.8, C =0), inuction an exhaust (C 1 =6.18, C =0) an cobustion an expansion (C 1 =.8,C =0.0034). T r, P r,v r =the reference teperature, pressure an volue respectively that we take the the initial conitions for copression stroke. B. Ignition Delay Ignition elay is the tie perio between the start of injection of fuel (t inj ) an the start of cobustion (t ign ). The start of injection is usually taken as the tie when the injector neele lifts off its seat. It is a coplicate function of ixture teperature, pressure, equivalence ratio an the fuel properties. It is best efine fro the change in slope of the heat release rate versus tie curve which occurs at ignition. The epirical relation is use to eterine the ignition elay is presente in the following equation [7]. (14) ID= the ignition elay in illi secon, E = apparent activation energy for the fuel autoignition process, Joule R= universal gas constant, 87 J/kg.K, P= the gas pressure in at, T = the gas teperature in K, t inj = the tie at which injection starts in illi secon, t ign = the tie at which ignition starts in illi secon an A, n, K inj = are constants epen on the fuel, injection an air characteristics. III. Forulation of The oel The ifferential first law of theroynaics for this oel for a sall crank angle change θ is inicate below: Q W U (16) The ieal gas equation of state as: PV R T (17) gas Q= the heat ae in kj, W= the work one in kj, U= the internal energy in kj, R gas =the gas constant (R gas =0.87 kj/kg.k), = the ass of the ixture in kg, P =the cyliner pressure in Pa, V = the cyliner volue in 3 an (15) T = the ean gas teperature in Kelvin. The total volue of the engine cyliner an the rate of its change are presente in the following equations: V V V ( ) ( )( R 1 cos( ) ( R r 1 V V ( (sin( )) )(1 (cos( ))( R (sin( )) (sin( ))) ) ) ) (18) (19)

4 International Journal of Engineering & Technology IJET-IJENS Vol:14 No:06 9 R l (0) L V = L = b = l = the swept volue of the engine in cubic eter, the engine stroke in eter, the engine bore in eter. the engine connecting ro length in eter an R=the ratio of connecting ro length to crank raius. The cyliner pressure an teperature in engine are calculate fro the following equations. P k 1 Q ha kp V ( )(( ) ( )( T Tw )) ( )( ) (1) V 6N V T T P T V ( )( ) ( )( ) () P V Solving the above equations with appropriate input ata enablesthe eterination of the pressure, teperature, specific fuel consuption an theral efficiency. IV. NUMERICAL AND COMPUTATIONAL METHOD Siulation coe was prograe using MATLAB software an the various equations of theroynaic oel were solve nuerically. The coputer coe is evelope to be suitable for any hyrocarbon fuel versus iesel, bioiesel an its blens. The engine geoetrical paraeters, olecular weight of gaseousproucts an the various constants use in the oeling are efine. The input paraeters use in the oeling are the copression ratio, relative air-fuel ratio an the olecular forula of the fuel. Fro the geoetry of the engine, the cobustion chaber volue at every crank angle egree is calculate. Wolfer s relation is use to eterine the ignition elay of gaseous ixtures. Heat release ue to cobustion of the ixture is calculate using Woschni heat transfer correlation. The pressure an teperature of the gases are calculate for every crank angle egree. The outputs of the oeling progra are instantaneous pressure, teperature, volue an the perforance paraeters that inclue specific fuel consuption an theral efficiency [8, 9]. A set of linear equations are solve nuerically: 1. Energy equation an ass balance.. First law of theroynaics for each zone (unburne an burne). 3. Equation of state. 4. Woschni heat transfer correlation. The coputational etho preicts the following paraeters: 1. Pressure, teperature an cuulative work one in the cyliner at every crank angle egree for bioieseliesel blens.. Specific fuel consuption an theral efficiency at engine ifferent loas for bioiesel- iesel blens. V.RESULTS AND DISCUSSION The increase in specific fuel consuption for ieselbioiesel blens (,, an ), preheate jatropha oil at a teperature of 90 C () an unheate jatropha oil copare to iesel oil are shown in Fig.1.The ecrease in theral efficiency for iesel-bioiesel bens (,, an ), preheate jatropha oil () an unheate jatropha oil copare with iesel oil are shown in Fig.. This is ue to lower viscosity, lower calorific value an lower volatility of fuel which leas to poor atoization an vaporization for fuel particles of iesel-bioiesel blens, preheate jatropha oil an unheate jatropha oil an hence low brake theral efficiency. Specific fuel consuption for iesel-bioiesel blens is lower than preheate an unheate oils.theral efficiencies for iesel-bioiesel blens are higher than preheate an unheate oils.

5 Theral efficiency, % Specific fuel consuption, kg/kw.hr International Journal of Engineering & Technology IJET-IJENS Vol:14 No: Fig.1.Variation of specific fuel consuption with brake power for bioiesel blens an preheating oil Fig..Variation of theral efficiency with brake power for bioiesel blens an preheating oil. The siulation results of preheate jatropha oil an unheate jatropha oil show lower peak pressures, peak teperatures an cuulative workone than iesel fuel as shown in Figs.3, 4 an 5. This is ue to jatropha oil higher viscosity, higher ensity an volatility causing poor atoization, ixture preparation an foration. The peak cyliner pressures, teperatures an cuulative workone are lower with preheate jatropha oil an unheate jatropha oil to iesel since the lower heating value of preheate an unheate oil are lower than that of iesel resulting in lower heat release.

6 Peak cyliner teperature, kw Peak cyliner pressure, bar International Journal of Engineering & Technology IJET-IJENS Vol:14 No: Fig.3.Variation of peak cyliner pressure with brake power for bioiesel blens an preheating oil Fig.4.Variation of peak cyliner teperature with brake power for bioiesel blens an preheating oil.

7 Cuulative workone, Joule International Journal of Engineering & Technology IJET-IJENS Vol:14 No: Fig.5.Variation of cuulative workone with brake powerfor bioiesel blens an preheating oil. VI. EXPERIMENTAL ANALYSIS A four stroke, Kirloskar type, irect injection, naturally aspirate single cyliner iesel engine, it has 85 bore, 110 stroke, copression ratio of 17.5an a rate brake power of 5. kw at 1500 rp, is use for the experiental analysis. The engine tests were carrie out on iesel engine using iesel,,, an as fuels. Jatrophaoill was use as a fuel as it was a non eible vegetable oil with properties close to iesel fuel. The engine was couple to an ey current ynaoeter an all experients were carrie out at constant rate spee of 1500 rp. A piezoelectric pressure transucer was installe in the engine cyliner hea in orer to easure the cobustion pressure. The average pressure ata fro 00 consecutive cycles were use for calculating cobustion paraeters. Signal fro the pressure transucer was fe to charge aplifier. An encoer provies electrical signals in the for of pulse trains, which can be translate into otion, irection, or position. Increental encoer is installe to easure the engine crank angle an easures the rotational otion of a shaft. An Inuctive proxiity sensor supplie a single pulse per revolution to ark TDC. Proxiity Switch can be use to sense the hea of a bolt attache to the shaft of the engine. VII. MODEL VALIDATION The ost straightforwar way to eterine the quality of the oel is to copare the oel results with the easure ata. Moel valiation is the ost iportant step in the oel builing sequence. Moel valiation quotes the static resiual error between the experiental an siulation ata. The coparison between experiental an theoretical cyliner pressure at rate spee of 1500 rp an full loa are shown in Fig.(6). The experiental an theoretical cyliner pressures have goo agreeent at rate spee of 1500 rp an full loa. The trens of the cyliner pressure curves for Jatropha bioiesel blens, preheate oil, unheate oil an iesel oels an experiental exhibit the sae tren. Also the preictions of the oel are very close to the experiental results. The peak pressure values fro siulation results, respectively, for iesel,,, an are about 57.19, 54.8, 51.55, 49.4 an bar. The peak pressure values fro experiental results, respectively, for iesel,,, an are about 59.7, 57.35, 5, 51. an 50 bar. The relative error of cyliner pressure between theoretical an experiental ata for iesel fuel is less than about 4%, the relative error of cyliner pressure between theoretical an experiental ata for is less than about 5 %, the relative error of cyliner pressure between theoretical an experiental ata for is less than about 1 %, the relative error of cyliner pressure between theoretical an experiental ata for is less than about 4 % an the relative error of cyliner pressure between theoretical an experiental ata for is less than about 4%.These results inicate that the assuptions of the oel are quite reasonable. The oel can be use to correctly preict iesel engine perforance burning bioiesel an preheate oil.

8 Cyliner pressure, bar International Journal of Engineering & Technology IJET-IJENS Vol:14 No: Crank angle, Degree (exp) (si) (exp) (si) (exp) (si) (exp) (si) (exp) (si) Fig.6.Siulation an experiental cyliner pressure for preheate, unheate jatropha oil an bioiesel blens. VIII. CONCLUSION Perforance characteristics of iesel engine fuele by iesel- bioiesel blens are investigate theoretically an experientally. The results inicate that: A single zone cobustion oel has been carrie out to preict the engine perforance in iesel engines. The oel results show that the relative error of cyliner pressure between theoretical an experiental ata for iesel fuel,,, an is less than about 4, 5, 1, 4 an 4%, respectively. There is quite goo agreeent between siulate an experiental results, which results inicate that the assuptions of the oel are reasonable. iesel engine", Worl Acaey of Science, Engineering an Technology, 001. [7] B.R.Prasath, P.Tailporai, an M.F.Shabir " Two- zone oeling of iesel/bioiesel blene fuel operate ceraic coate irect injection iesel engine", International Journal of Energy an Environent, Vol.1, pp , 010. [8] S.S.Panian, G.Devarajane," Theortical an experiental investigation of the perforance of vegetable oil operate CI engine", Deapartent of Autobile Engineering, Maras, Institute of Technology, Anna University, 009. [9] N.V.Deshpane, M.K.Manani,A. Joshi et al," Siulation an analysis of cobustion an heat transfer in low heat rejection iesel engine using two zone cobustion oel an ifferent heat transfer oels", SAE , 003. REFERENCES [1] J.B.Heywoo, "Internal Cobustion Engine Funaentals", McGraw-Hill Inc.,ISBN X, New York, [] N.Watson, "Turbocharging the Internal Cobustion Engine", Mac- Millanpub.Lonon, [3] A.S.Raahas, S.Jayaraj, C.Muraaleeharan,"Theortical oeling an experiental stuies on bioiesel-fuele engine", Renewable Energy, Vol.31, pp , 006. [4] M.P.Sueshkuar,G.Devarajane," Developent of a siulation oel for copression ignition engine running with ignition iprove blen", Theral Science, Vol.15, pp , 011. [5] D.Jagaish, R.K. Puli, K.M.Murthy,"Zero iensional siulation of cobustion process of a DI iesel engine fuelle with biofuels", Worl Acaey of Science, Engineering an Technology, Vol.80, pp , 011. [6] B.R.Prasath, P.Tailporai, an M.F.Shabir " Theortical oeling an experiental stuy of cobustion an perforance characteristics of bioiesel in turbocharge low heat rejection D.I