Experimental and Numerical Analysis of the Test Section Slots in Wind Tunnels

Sergio Antonio de Oliveira Neto¹; Ana Cristina Avelar¹; João Batista Pessoa Falcão Filho¹; Layra Mendonça Silva¹

¹ IAE

doi:10.20906/CPS/COB-2015-1939

Resumo

The Institute of Aeronautics and Space (IAE) has in its Aerodynamic Division (ALA) the Pilot Transonic Wind Tunnel (TTP) which is a scaled down 1:8th from an industrial facility. One of the tunnel objectives is to support research in the transonic range, helping the development of sounding rocket and satellite launcher vehicles. A long term test campaign has been undertaken to assess the pressure distribution over a NACA0012 profile as the scientific literature gives abundant theoretical and experimental results and they can be utilized in comparisons. With the aim of understaning the aerodynamic behavior of the tunnelthe present work utilizes numerical simulation techniques to investigate the tunnel functionalities, concerning the behavior of the test section slotted walls. Both conditions with solid and slotted walls are simulated numerically and experimentally for theNACA0012profile with a chord of 83 mm installed in the test section. Pressure distribution over the profile is obtained both with conventional pressure taps and with PSP technique (Pressure Sensitive Paint). The results are compared in order to confirm with both approaches the effectiveness of the slotted walls in suppressing the wave reflections and the wall presence. The numerical simulation solves the Euler equations in two-dimensional, generalized coordinates, centrally centered cells in structured grid. Mach numbers ranging from 0.4 to 0.85 are analyzed in the study cases and the slotted walls are simulated in a particular procedure to be representedby a two-dimensional simulation. The pressure at the slots is varied to investigate the effect of the plenum chamber pressure control system.

Palavras-chave: Aerodynamics; Transonic; Wind Tunnel; PSP