Shiraz University Iranian Journal of Science and Technology Transactions of Mechanical Engineering 2228-6187 39 M2 2015 10 01 NUMERICAL INVESTIGATION OF THE UNSTART SUPPRESSION IN A SUPERSONIC AIR INTAKE 413 426 3249 10.22099/ijstm.2015.3249 EN M.R. Soltani Dept. of Aerospace Engineering, Sharif University of Technology, Tehran, I. R. of Iran J. Sepahi Yoinsi Dept. of Aerospace Engineering, Sharif University of Technology, Tehran, I. R. of Iran and Mesbah Research Institute, Tehran, I. R. of Iran V. Farajpoor Khanaposhtani Mesbah Research Institute, Tehran, I. R. of Iran Journal Article 2014 06 08 The starting behavior of a supersonic axisymmetric mixed compression air intake was numerically investigated. The code solves Reynolds-averaged Navier–Stokes equations using an explicit finite volume method in a structured grid by the Roe flux difference splitting scheme. Further, it uses the Baldwin–Lomax algebraic model to compute the turbulent viscosity coefficient. The correct method of surveying the intake starting problem and effects of several geometrical parameters such as: intake throat area, cowl lip roundness and spike surface curvature upstream of the throat on the starting and performance of the intake were studied. Results showed that correct combinations of the mentioned parameters can suppress the intake unstart problem and in addition can prevent the reduction of the intake efficiency. https://ijstm.shirazu.ac.ir/article_3249_89353845fdcb78d1ec94448d965d3d97.pdf