Ramin Kamali Moghadam; Mohammad Reza Salimi
Volume 8, Issue 4 , January 2016, , Pages 19-27
Abstract
An accurate and efficient computational procedure is developed to predict the laminar hypersonic flowfield for both the perfect gas and equilibrium air around the axisymmetric blunt body configurations. To produce this procedure, the boundary layer equations utilize the integral matrix solution algorithm ...
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An accurate and efficient computational procedure is developed to predict the laminar hypersonic flowfield for both the perfect gas and equilibrium air around the axisymmetric blunt body configurations. To produce this procedure, the boundary layer equations utilize the integral matrix solution algorithm for the blunt nose and after body region by using a space marching technique. The integral matrix procedure enables us to create accurate and smooth results using the minimum grid in the boundary layer and to minimize the computational costs. This algorithm is highly appropriate for the design of hypersonic reentry vehicles. The effects of real gas on the flowfield characteristics are also studied in boundary layer solutions. Comparisons of the results with experimental data demonstrate that accurate solutions are obtained.
S. A. Hosseini; S. Noori
Volume 7, Issue 1 , April 2014, , Pages 33-40
Abstract
In the present work, an engineering method is developed to predict laminar and turbulent heating-rate solutions for blunt reentry spacecraft at hypersonic conditions. The calculation of aerodynamic heating around blunt bodies requires alternative solution of inviscid flow field around the hypersonic ...
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In the present work, an engineering method is developed to predict laminar and turbulent heating-rate solutions for blunt reentry spacecraft at hypersonic conditions. The calculation of aerodynamic heating around blunt bodies requires alternative solution of inviscid flow field around the hypersonic bodies. In this paper, the procedure is of an inverse nature, that is, a shock wave is assumed and calculations proceed along rays normal to the shock. The solution is iterated until the given body is computed. The inverse method is practical for the calculation of flow field between the shock wave and the body surface. Body calculation with the body analysis is contrasted and according to the entire differences between those; the shape of shock with the coefficient scales is implemented. The normal momentum equation is replaced with a Maslen’s second order pressure equation. This significantlysignificantly decreases machine computation time. The present method predicts laminar and turbulent heating-rates that compare favorably with other researches. Since the method is very high-speed, it can be used for preliminary design, or parametric study of aerodynamics vehicles and thermal protection of hypersonic flows.
R. Kamali –Moghadam; S. Nouri; M. R. Salimi; M. Sheida; S. A. Hosseini
Volume 6, Issue 3 , October 2013, , Pages 39-48
Abstract
When a solver is used for analyzing the hypersonic reentry vehicles, high speed and accuracy of the solver results are the basic parameters in the design process. In the present study, the results obtained by solution of laminar boundary layer equations using integral matrix method and approximate method ...
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When a solver is used for analyzing the hypersonic reentry vehicles, high speed and accuracy of the solver results are the basic parameters in the design process. In the present study, the results obtained by solution of laminar boundary layer equations using integral matrix method and approximate method are assessed in aeroheating prediction around hypersonic axisymmetric reentry bodies. The results show that the applied methods have suitable accuracy in aeroheating and high computational speed for reentry vehicle design. Space marching method in numerical simulation of boundary layer equations and applying less grid point in the boundary layer due to use of integral matrix method rather than other methods efficiently decrease computational costs. Also, high robustness of approximate method in the heat flux prediction over the reentry surface makes it useful for design process.Using a special approximate relation for stagnation region improves the aero-thermodynamics results.