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In the present study, develop the multi zone thermodynamic model for the simulation of a small diesel engine operating on the mixture of diesel and ethanol and comparing results with an experiment. This paper discussed analytically and provides data of nitrogen oxide and performance parameters such as power, speci-20 Paramust Juntarakod and Thanakom Soontornchainacksaeng fic fuel consumption and thermal efficiency, indicated mean effective pressure. For this purpose, quasi-dimensional phenomenological three zone combustion process (unburned, adiabatic core region and boundary layer gas) has been modeled based on equilibrium constants method with MATLAB program to calculate the mole fractions of 11 combustion products when the new equilibrium constants function developed by Gill which are lowly-highly temperature dependent. To compute diesel engine cycles, zero-dimensional compression and expansion model have given by Ferguson and developed with new assumptions. These results involve various combination sequence effects of compression ratio (23-25), equivalence ratio (0.8-0.9), burn duration angle (60-70 CA) and engine speed (1000-1500 rpm) which volume fraction of fuel compositions (10-30% ethanol) (Diesel-Ethanol blend). The results of the study as the power was calculated by this method are the error range within around 5% or 0.5 kW from the maximum experiment results. The specific fuel consumption was less than 5% or 15-20 g (Fuel)/kW-hr from experiment results. The resulted show that nitrogen oxide has changed very little, corresponding results of various sequence effects. The performance parameters were changed with varying engine computing conditions. Maximum performance parameters be raised by increases the engine speed and equivalence ratio, its can increase the thermal efficiency are approximately value 15-20%.

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A quasi one-dimensional engine cycle, the simulation program was developed to predict the simple heat transfer during combustion stroke in a spark ignition engine (SIE) of ethanol-gasoline blended fuels. A two-zone heat release model was utilized to model the combustion process inside the combustion cylinder by using high order iteration method (HIM) in combustion equation. The fuel, air and burned gas properties throughout the engine cycle were calculated by using variable specific heats. The transient heat flux inside the combustion chamber due to the change in the cylinder gas temperature and pressure during combustion was determined by using the constant of heat rate from enthalpy heat rate coefficient. The program was written in MATLAB. The results of this paper such as the average heat flux cycles of the burned gas during the combustion and showing the emissions of at during the combustion process by high iteration method. Based on these results, it was concluded that the fundamental thermodynamic properties of the fuel, air, and combustion product species were in agreement with previously published results to within the scatter of those results typically less than 1% form references 1%. The combustion products were calculated by the high order iteration methods by around 1% from the old methods.

For a specific combustion problem involving calculations of several species at the equilibrium state, it is simpler to write a general computer program and calculate the combustion concentration. Original work describes, an adaptation of Newton-Raphson method was used for solving the highly linear system of equations describing the formation of equilibrium products in reacting of fuel-additive-air mixtures. This study also shows what possible of the results. In this paper, it presents the efficient numerical algorithms for solving the combustion problem, to be used linear equations based on the iteration method and high order of the Taylor series. The modified the Adomian decomposition method was applied to construct the numerical algorithms. Some numerical illustrations are given to show the efficiency of algorithms. Comparisons of results by the new Matlab routines and previous routines, the result data indicate that the new Matlab routines are reliable and application with gasoline and biogas with the variance of equivalence ratios, typical deviations from previous results are less than 0.1%.