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A three-component balance is designed and constructed for
shock tunnel hypersonic flows. Static calibration and
modal testing reveal that the frequency response of the
balance are well above 1kHz,and the drag-component has a
frequency response of 4.4kHz, which agree very well with
finite element simulation (MSC/NASTRAN). The cross-talk
between the components of balance is relatively small.
The model support is separated from the tunnel test
section to isolate the vibration of the shock tunnel
facility. Since the test time of tunnel at the exit is
about 9.5 ms, the balance response can provide force/moment
data more than 3 cycles of oscillation.
The experimental data shows that the drag coefficient of
a 60°cone is 0.58 ,which fall closely to the curve in
literature. The forces measurements for a cone-cylindrical
body with canard-control surface show clearly that the
lift force and pitch moment increase with control surface
deflection or angle of attack. The drag force also increased,
but the control effectiveness for low-density hypersonic
flow is relatively small as expected. However, the model
itself is too long to causes aerodynamic interference,
the control effectiveness can not be defined quantitatively
at present.
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