A novel free floating accelerometer force balance system for shock tunnel applications
In order to overcome the interference of the model mounting system with the external aerodynamics of the body during shock tunnel testing, a new free floating internally mountable balance system that ensures unrestrained model motion during testing has been designed, fabricated and tested. Minimal friction ball bearings are used for ensuring the free floating condition of the model during tunnel testing. The drag force acting on a blunt leading edge flat plate at hypersonic Mach number has been measured using the new balance system. Finite element model (FEM) and CFD are exhaustively used in the design as well as for calibrating the new balance system. The experimentally measured drag force on the blunt leading edge flat plate at stagnation enthalpy of 0.7 and 1.2 MJ/kg and nominal Mach number of 5.75 matches well with FEM results. The concept can also be extended for measuring all the three fundamental aerodynamic forces in short duration test facilities like free piston driven shock tunnels.
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- 1.M. Takahashi, T. Komuro, K. Sato, K. Itoh, H. Tanno, S. Ueda: Development of a new measurement method for Scramjet testing in a high enthalpy shock tunnel. AIAA 99-4961 (1999)Google Scholar
- 2.W.H. Rae, A. Pope: Low Speed Wind Tunnel Testing. (Wiley, New York 1984)Google Scholar
- 4.Niranjan Sahoo, D.R. Mahaptra, G. Jagadeesh, S. Gopalakrishnana, K.P.J. Reddy: Aerodynamic force measurement on 60 deg. apex angle blunt cones flying at Mach 5.75 using a 3-component accelerometer balance. AIAA 2002-5204 (2002)Google Scholar