Modeling and analysis of jet engine with cooling turbine

The problems of the turbojet engines with a cooling turbine modelling are discussed in the paper. The cooling systems of the contemporary jet engines are briefly described in the first part of the paper. Than the models of various turbine, cooling systems are presented and discussed. The main scope of the paper is the turbine cooling system consisted of internal convection cooling and external film cooling of turbine blades. This cooling system is commonly used in contemporary military and civil turbojet engines. The model of the internal-external cooling turbine incorporated in the overall jet engine model is presented and discussed. Some simplifying assumptions are discussed. Then the results of the jet engine calculation taking into account the proposed model are presented in the tables. The results are compared with results obtained by simple model of the jet engine with cooling turbine. The simple model is commonly applied for 1D turbojet engine analysis. Based on this analysis, some aspects of the turbojet engine calculation with reference to different models applied for description of the turbine cooling process are presented and discussed. The analysis allowed formulating some conclusions, which are presented in the final part of the paper. One of them is that proposed model of cooling turbine allows to calculate of coolant mass flow, while the simple models of cooling turbine require the assumption of coolant mass. By this way the calculation results accuracy by the use of simple model, strictly depend on the proper assumption of coolant mass flow.