Increasing the temperature of the turbine entrance gases increases the efficiency of the gas turbine cycle. Under these conditions, the combustion chamber wall temperature also increases, while there is no high temperature resistance alloy fitted with air motors. Therefore, it is necessary to use cooling methods to reduce the wall temperature. In this study, the cooling effect with compound angles investigated on the combustion chamber wall temperature. The three-dimensional combustion chamber k-ɛ is modelled under the conditions of the input speed and the turbulence model in the ANSYS Fluent software. Inlet air is injected from the cooled holes to the mainstream with compound angle, where the cooling flow angle is constant with the 30° horizontally, and the lateral angle changes from Beta =0 up to Beta=60 degrees. The combustion chamber has two flat planes and two sloping plates, in which the arrangement of cooling holes is different. The results show that this method better distributes the cooling air on the wall surface and covers the space between the cooling holes, especially on flat plates. With this method, the number of cooling holes and the amount of air used to cooling can be reduced. تفاصيل المقالة

To ensure the correct design and proper operation of turbine engine components, various types of ground tests must be performed, which requires the simulation of the input flow to these components. To test hot components such as nozzles, it is necessary to create a hot flow, which is done by the preheat system of the inlet flow. For the ground test of the nozzle of a turbofan engine that has an afterburner in addition to the combustion chamber, the preheat system must be able to supply air in two modes, dry mode and reheat mode. In this paper a combustion chamber with an afterburner is used to provide hot air to the nozzle. In the first step, using experimental and analytical relations, the combustion chamber is designed. The presented algorithm has the ability to calculate the diameter and reference surface of the combustion chamber, components of the combustion chamber and thermodynamic parameters. Then the obtained results are compared with the data of a similar annular combustion chamber. The comparison indicates the acceptable convergence of the design results with the experimental results. Finally, the output flow of the combustion chamber is considered as the input of the afterburner, and the temperature of the combustion flow is increased by the afterburner to the desired temperature. In addition to the ability to design a V-gutter flame keeper, the afterburner design algorithm also calculates the thermodynamic characteristics of the afterburner output stream, considering the requirements of flame stability. تفاصيل المقالة