AN ANALYTICAL AND NUMERICAL MODEL OF RADIATION HEAT TRANSFER IN DIRECT INJECTION-TYPE DIESEL COMBUSTION

This thesis is a result from a multi-task diesel combustion research implemented at Rutgers university since early 1980. The research has been directed to a better understanding of the processes of particulate formation and radiation heat transfer in direct injection-type diesel engine combustion.; The dissertation considers an analytical and numerical model of radiation heat transfer in a combustion reactor containing soot-laden flames as an immediate application to the direct injection-type diesel engine. The governing equation of the radiation heat flux and the coordinate transformation that replaces the geometric factors are analytically derived by employing unique techniques, e.g., a new radiation integral function. And the final form of equations are solved by using the Gauss numerical integration technique.; The present model enables one to compute the spectral emissivity of a given volume of combustion products, and further, to find, for the individual optical paths, the spectral incident radiation flux on the wall of a combustion chamber with known species distribution. By incorporating with the spectral emissivity of the wall and by integrating over the hemispherical volume of combustion product and the entire thermal radiation spectrum range, the energy transferred through the individual locations of the chamber by radiation is computed.; By using the model, a limited range of a parametric study has been conducted on radiation heat transfer in direct injection-type diesel combustion. Upon the combination of the model with conduction and convection heat transfer models, an in-depth parametric analysis of the heat transfer in the diesel combustion is carried out as a continuation of the present work.