A Balance for Measurement of Yaw , Lift and Drag on a Model in a Hypersonic Shock Tunnel
Lift and Drag on a lifting model with typical control surfaces, in a hypersonic impulse facility. The model used in the present study is a blunt-nosed triangular plate attached with flaps. The experiments were carried out at a freestream Mach number of 8 in a hypersonic shock tunnel, with air as the test gas, where the test time was about 1.2 milliseconds. The experiments were repeated at different angles of incidence of the model and the coefficients of Yawing moment (C Y), Lift (C L) and Drag (C D) were deduced based on the acceleration signals obtained from the balance. Measured values of the moment and force coefficients were compared with the theoretical results predicted using the Newtonian theory.
An accelerometer balance system for measurement of aerodynamic force coefficients over blunt bodies in a hypersonic shock tunnel
A miniature three-component accelerometer balance system for measuring the fundamental aerodynamic force coefficients over blunt bodies has been designed, fabricated and tested in the Indian Institute of Science hypersonic shock tunnel HST2 at a nominal Mach number of 5.75. The model and the balance system are supported by rubber bushes, thereby ensuring unrestrained free-floating conditions of the model in the test section during the flow duration. Exhaustive axisymmetric finite-element simulations are carried out to select appropriate rubber bushes and materials for the model and the balance system. The internally mountable accelerometer balance is used to measure the drag, lift and pitching moment coefficients for a $60^o$ apex angle blunt cone within the effective tunnel test time of $800\hspace{2mm}{\mu}s$. The measured aerodynamic force coefficients match very well with the theoretical values predicted using modified Newtonian theory at moderate specific enthalpy levels of the test gas.
The University of Queensland free piston shock tunnel T-4: Initial operation and preliminary calibration
The University of Queensland free piston shock tunnel T-4 is the latest in a series of free piston shock tunnels, the first three of which were constructed at the Australian National University, Canberra, in the 1960's. The complete series is shown to scale in fig. 1, and is marked by an increase in size in passing from one to the next.