Применение циклической симметрии и метода подконструкций в термопрочностном расчете камеры сгорания ЖРД с кислородным охлаждением

The problem of stress-strain analysis of the combustion chamber and the nozzle of the cruise liquid-propellant rocket engine with LOX cooling is discussed in this article. The authors propose a comprehensive finite element method for mathematical modelling of the structure, which makes the design and calculation stages less labour intensive. The method is based on the application of the cycle symmetry principles. It is reduced to the analysis of critical areas using the substructure method, which allows reducing the dimensionality of the problem. The laws of temperature and pressure variations for three typical operating modes are considered as known. The cyclic loading simulation in the physically non-linear formulation is performed in the ANSYS environment. The stress-strain states of the structure are evaluated as a result of the calculations. The zones of possible destruction that are caused by the low-cycle fatigue are identified. The proposed method has proved its useful purpose and can be recommended for implementation in order to reduce expensive fire tests.