Configurable combustion models of combustion chamber of microturbine engine with possibility of connecting various physico-chemical processes

Abstract

Mathematical and numerical models of the combustion of a fuel mixture in the combustion chamber of a microturbine engine have been developed. Complexity of the models can vary, which gives developers a fairly convenient calculation and design tool. Models allow to take into account the required design tasks by considering and not taking into account various physical processes, and create an optimal complexity model for each specific case. The development of the required configuration begins with the consideration of a simple model of the global kerosene in air combustion reaction without conjugate heat exchange with solids. Step by step, models of extended kinetics, swirling flow, radiation, heat exchange with walls, and the presence of lubricant oil in kerosene are added to the calculation methodology. The results of calculating the wall temperature and combustion completeness were compared with those of JetCat P100-RX and P550-PRO turbojet engines, the integral characteristics of which are well known. In the course of the performed computational and experimental studies, a comparison of the run-off spots on the walls of the combustion chamber with the calculated temperature distributions was performed. A good agreement of the results was obtained for the complete mathematical model. The effect of better cooling of the combustion chamber and increasing the completeness of combustion by twisting the flow behind the compressor is revealed. The effect of the addition of oil to kerosene on an increase in specific fuel consumption by 1–4 % has been determined. The significance of the results obtained lies in the possibility of applying the proposed calculation methodology in engineering practice. The considered modifications of the model represent an important stage in the creation and verification of a mathematical model of in-chamber processes.

Keywords

• micro gas turbine engine
• combustion chamber
• numerical simulation
• validation