Session: K12-02 Aerospace Heat Transfer II

Paper Number: 111724

111724 - Heat Transfer Characteristics Over Supersonic and Hypersonic Flow Over an Airfoil 

The heat transfer characteristics of high-speed air flow over an airfoil initially at temperatures of 200K and 300K, respectively, are  investigated. The airfoil is a NACA0012 standard with chord length of 1-meter, maximum thickness of 0.12 meter and a distance of 0.3 meter from leading edge to the maximum thickness section. The CFD model used in this paper was validated by experimental visualization studies in the evaluation of the oblique shocks formed on a similar airfoil under supersonic flow conditions. The experimental  parameters for the pressure, density and Mach number are 21 KPa, 0.363 kg/m³, and 1.5, respectively. The airfoil geometry was modified to resemble that of the experiments. The  comparison between the current model pressure field predictions and  the visualization studies from the experiment is excellent.    

For the present simulations, the free-stream air flow velocity is set at various Mach number regimes (transonic and hypersonic). The 2D mesh elements simulate a wind tunnel with an inlet of 8.0 meters and total width of 8.5 meters, with the airfoil at the center. The mesh density was increased near the airfoil to simulate the boundary layers over the surface of the foil. The LSTC transient solver LS-DYNA is used to generate different resulting shock wave formation using the space time CESE (Conservation Element and Solution Element) method. For about 20 cm from the airfoil surface, the temperature profile near the location of maximum thickness of the airfoil were collected from the solver and the Fickian heat flux was calculated. It was found that for transonic flows, increasing the Mach number towards the transonic flow would decrease the heat flux from the airfoil to the air flow; and for hypersonic flows, increasing the Mach numbers would increase the  heat flux going into the airfoil. This indicates that frictional heating exists for objects subjected under subsonic to transonic air flows.

Presenting Author: Bakhtier Farouk Drexel University, MEM Dept