A series of supersonic wind tunnel tests on an ogive-cylinder body were performed to investigate the pressure distribution, the boundary layer profiles, and the flow visualization at various angles of attack. All tests were conducted in the trisonic wind tunnel of the Imam Hossein University. The theoretical shock angle at different model positions compared well with those we obtained via Schi...

In this paper, the similarity solution of turbulent boundary layer flow on the flat plate with zero pressure gradients is presented. By employing similarity variables the governing partial differential equations are transformed to ordinary ones with inconsistent coefficients and solved numerically with the use of Runge–Kutta and shooting methods in conjunction with trial and error procedure. Fo...

‎in the present analysis‎, ‎we study the boundary layer flow of an incompressible viscous fluid near the two-dimensional stagnation-point flow over a stretching surface‎. ‎the effects of variable thickness and radiation are also taken into account and assumed that the sheet is non-flat‎. ‎using suitable transformations‎, ‎the governing partial differential equations are first converted to ordin...

phase inversion in liquid-liquid dispersions corresponds to the transitional boundary between oil-in-aqueous dispersion and aqueous-in-oil dispersion. a theoretical model based on simple assumptions was proposed to predict phase inversion point, ambivalence region and the hysteresis effect of inversion. experimental data from the literature were used to validate the model and results were compa...

The current study presents the results of the aerodynamic noise prediction of the flow field around a NACA 0012 airfoil at a chord-based Reynolds number of 100,000 and at 8.4 degree angle of attack. An incompressible Large Eddy Simulation (LES) turbulence model is applied to obtain the instantaneous turbulent flow field. The noise prediction is performed by the Ffowcs Williams and Hawkings (FW-...

in this paper, we investigate a singular perturbation problem including a fourth order o.d.e. with general linear boundary conditions. firstly, we obtain the necessary conditions of solution of o.d.e. by making use of fundamental solution, then by compatibility of these conditions with boundary conditions, we determine that, for given perturbation problem, whether boundary layer is formed or not.

Roughness elements in high speed flows can cause laminar-turbulent transition leading to higher heating rates and drag. Transition of flow past a hemispherical bump placed on a flat plate is explored in this paper for three Mach numbers [3.37, 5.26, 8.23] using direct numerical simulation on unstructured grids. The simulation parameters are chosen to match the experiments carried out by Danehy ...

This paper presents a study of high speed boundary layers using the wavelet method. We analyze direct numerical simulation data for high-speed, compressible transitional, and turbulent layer flows orthogonal anisotropic wavelets. The wavelet-based method extraction coherent structures is applied to flow vorticity field, decomposed into incoherent contributions thresholding coefficients. show th...