Контроль параметров процесса наполнения газопоршневого двигателя методом малых отклонений

Abstract

A mathematical model of estimation of thermal and effective parameters of the most important part of cogeneration system of gas piston engine working in cogeneration mode was developed. Parameters of fresh air intake stroke with variable conditions of the environment using the method of small deviations were studied. The advantages of using the method of small deviations are the possibility of linearization of calculation equations as well as making calculations of not absolute but relative parameter change. The main parameters of fresh air intake by a cylinder are parameters of combustible mixture at the end of the intake stroke: combustible mixture pressure pa, the level of compression ε, the level of heating of fresh charge during the intake ΔT, parameters of residue gases (quantity Mr, pressure pr and temperature Tr), temperature of combustible mixture Tк. Using the method of small deviations for estimation of influence of the temperature of combustible mixture on effective values of gas piston engine led to an important finding: relative change of specific effective fuel consumption (economical part of gas piston engine exploitation) is in reverse relation to squared relative difference of temperature of supercharging air. In addition, cooling of supercharging air will positively influence temperatures inside engine cylinders and consequently fuel burning temperature. In turn, lowering the fuel burning temperature will improve ecological impact of the engine and reduce exhaust of harmful components into the atmosphere, in particular NOx.