Metodologia numérica para análise e caracterização do spray de combustível e da combustão em um motor de combustão interna com injeção direta

Abstract

The computer simulation for spray and combustion of an internal combustion engine represents a major challenge as new technologies and systems that seek reduction of fuel consumption and lower emissions. New technologies such as a centimeter-ignited direct fuel pump have suffered from fuel and source support from fossil energy sources, which produce increasingly efficient and less polluting roles. With the help of technology in the automotive market, fuel spray characterization by the injector is important to increase combustion efficiency and leave abnormal combustion. However, characterizing spray and combustion is not an easy task, both experimentally and numerically. This content, is found in Portuguese the spray and the fuel of internal fuel injection in the fuel of internal fuel. Given the academic and business interest in the open CFD cipher, OpenFOAM software is found in this work, my source code is freely available for implementation. Spray dispersion models such as LISA, TAB, Reitz-Diwakar and KHRT, which are already available in OpenFOAM, are used and modified to make the dynamometer test experiment data converge and the results are compared to the proposed new models. Important spray parameters, break angle, cone angle, penetration, drop diameter, drop dispersion, velocity fields, among others, are calculated according to the newly designed models. The characterization of combustion is generated by new mathematical forms that can typify a laminar flame velocity, a demand and an average combustion, as well as the parameters that characterize as turbulence fluctuations and turbulence itself. The results show that in the characterization of the second spray break, the graphs were analyzed and compared with the experimental and literature data. The elaborate collision model was a modified form of O'Rourke's model, which is not only once, but the collections are in the same cell, the new algorithm calculates the trajectory of all packets and collides with those that intersect. in the same time frame. The laminar flame results show that the combustion and pressure rates are not increased, which is a speed for doubling and an important insulation temperature in half. The results further show that the mean and temperature of the cylinder are influenced by differences in combustion temperatures. However, the combustion temperature has little effect on Reynolds average progress.