and Computational Methods

doi: 10.18698/2309-3684-2023-4-1526

The work is devoted to numerical studies of detonation initiation in a gas mixture in a rectangular channel with a profiled end. Detonation is initiated as a result of the interaction of shock waves which are formed as a result of the reflection of an incident shock wave of relatively low intensity from the end of the channel. The mathematical model includes the system of gas dynamics equations supplemented by Arrhenius kinetics for a model hydrogen-oxygen mixture with tabular kinetic parameters corresponding to the operating range of pressures and temperatures of the mixture. Numerical calculations are carried out using the finite volume method. The construction of computational grids consisting of triangular cells is carried out using the free software SALOME. The numerical algorithm is parallelized by the computational domain decomposition method using the METIS library. The exchange of grid functions between computational cores is carried out using the functions of the MPI library. The problem of acceleration of the parallel algorithm realized in the code is considered in comparison with the case of the linear dependence of the number of computational cores. A number of calculations were carried out using a different number of triangular cells and a comparison of patterns of detonation initiation was carried out. The performed calculations show that the detonation initiation time is approximately the same in all computations. The main difference in detonation patterns is associated with gas flow and Physical and chemical reactions in the mixture.

Лопато А.И. Математическое моделирование инициирования детонации в канале с профилированным торцом с использованием параллельных вычислений. Математическое моделирование и численные методы, 2023, № 4, с. 15–26

doi: 10.18698/2309-3684-2024-3-6580

The work is dedicated to the numerical study of pulsating gaseous detonation wave propagation. The mathematical model is based on the Euler equations written for the multicomponent gas and supplemented by the detailed chemical reactions model of Petersen and Hanson. to describe the combustion of the hydrogen–air mixture. This kinetics model is effective and efficient in describing processes in hydrogen-air and hydrogen-oxygen mixtures. The numerical algorithm is based on the finite volume approach, essentially non-oscillatory scheme, AUSM numerical flux and the Runge–Kutta method for time integration. Direct initiation of detonation at the closed end of a channel filled with a stoichiometric hydrogen-air mixture is considered. Mathematical modeling of the propagation of a pulsating detonation wave was carried out. The peculiarities of high-frequency and high-amplitude pulsations modes are discussed.

Лопато А.И. Математическое моделирование распространения пульсирующей волны газовой детонации в водородно-воздушной смеси с использованием детальной кинетики химических реакций. Математическое моделирование и численные методы, 2024, № 3, с. 65–80.