A Computer Code to Model Swept Wings in an Adaptive Wall Transonic Wind Tunnel

A computer program has been developed to calculate inviscid transonic flow over a swept wing in a wind tunnel with specified normal flow at the walls. An approximately orthogonal computational grid which conforms to the wing and the tunnel walls was developed for application of the JamesonCaughey finite volume algorithm. the full potential equations in fully conservative form using line relaxation. This program is to be used in place of the wind tunnel for preliminary studies of the adaptive wall concept for three dimensional configurations. It can also be used to assess the magnitude of wall interference in a conventional tunnel. Introduction The code solves It is possible to simulate free air flow about a wind tunnel model by controlling inflow and outflow through parous or slotted tunnel walls. correct normal flow distribution changes with model configuration, angle of attack and Mach number and is not known apriori. It has been proposed by Ferri and Barontil and by Sears2 to match the flow field provided by the tunnel to a computed flow field beyond the tunnel walls by an iterative adjustment of the boundary conditions at the interface of these two regions. This wedding of the wind tunnel and the computer eliminates the major problems associated with using either of these tools by itself, namely the incorrect flow constraints of the tunnel walls, and the inaccuracy andlor the expense of near field flow calculation, particularly for transonic flow and separated flow. The