The purpose of this paper is developing a method for simulation of a cryogenic staged combustion-closed cycle engine. Since, aerospace systems are usually complicated and important; the simulation task becomes extremely important. If the propulsion system of space vehicle is not successfully simulated, then designers must rely on huge tests which are time and money consuming and also dangerous. The mathematical model of the engine includes a set of equations which describe all the system's elements operation. These equations correspond to mass, momentum and energy conservation principles and are simplified to make easy the process of calculations. A Fortran 90 code is developed for this simulation. Comparison of the simulation code with the actual values, demonstrates that the model can accurately predict the behavior of the real engine

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In this article, the impact of external uniform magnetic field on the dynamic characteristics and mixing parameters of two-dimensional isotropic magnetohydrodynamic (MHD) flow is investigated. For this purpose, the direct numerical simulation (DNS) is applied to two-dimensional incompressible Navier-Stokes and magnetic induction equations by pseudo-spectral method. Governing equations are considered in the N-S vorticity equations to guarantee the incompressibility conditions and remove the pressure term from equations. The Results of the calculations show that the deformation of vortexes by external magnetic field reduces the mixing efficiency. It is also demonstrated that in MHD flow the energy is exchanged by Lorentz force between the flow and the magnetic field in such a way that the kinetic energy decreases and consequently mixing of the fluid is reduced. This energy transfer causes reduction of viscous dissipation of energy and mixing efficiency, despite increasing the total dissipated energy rate.