Effects of Forward-Speed on the Ambient Pressure around ACVs

Abstract

This paper deals with the effect of forward speed on the front and ambient pressure of a peripheral-jet air cushion vehicle.
The experiments are conducted with a twodimensional rectangular-shaped model in a moving ground wind tunnel. The peripheral-jet air is brought into the model through ducts at either side. The static pressure distribution, on the both side plates and on the front, rear and bottom surfaces of the model, have been measured in this experiments.
The results are summarized as follows:
(1) At subcritical speed, the semi-emperical analysis has been performed by applying the horizontal momentum balance at the reverse jet flow region of the front of the model. Calculated front pressure agree well with the experimental results.
(2) The front pressure at subcritical speed increases as the jet momentum coefficient decreases, i.e. when the wind velocity is increased.
(3) At near critical and supper critical speed, the front pressure coefficients are approximatly 1.0.
(4) The wake pressure coefficients are nearly equal to -0.85.