Scramjet combustor design is a quite complex task because of the strong interactions between the several engine components such as inlet, Isolator, combustor and nozzle. One is neither able to calculate real internal flows with an analytical approach, nor are 3D CFD computations suitable for conceptual engine design processes because of the enormous efforts in grid generation and computing time. Therefore, in this paper a one-dimensional approach was applied that allows good assessment of the flow and parametric studies for the engine design process. At the Institute of Aerospace Thermodynamics Universitat Stuttgart, Germany, a code was developed that solves the one-dimensional conservation equations and the equation of state with the help of a 4th Order Runge-Kutta method. It includes source terms for mass addition and area distribution to calculate the basic thermodynamic properties such as temperature, pressure and Mach number. The flow is treated as a thermally perfect gas, where specific heat capacity and specific heat ratio are functions of temperature only. Wall friction is accounted for by using either friction coefficient or compressible boundary layer correlations. Additionally, heat transfer effects are included. In most studies, dealing with one-dimensional analysis of combustor flows, the fuel mixing is realized by continuous fuel mass addition. In the present paper, fuel injection and fuel mixing are completely decoupled as they are in real scramjet flows. Heat release due to combustion is modelled in a separate module either with chemical equilibrium or chemical kinetics. This allows the simulation of strong combustion and weak combustion, respectively. In the present paper, the governing equations of the flow-module and reaction-module are presented as well as the implementation of several physical effects such as fuel injection and fuel mixing. Finally, the limits of this approach as well as a comparison with experimental investigations are presented.
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