Suppression of oscillations of piston-aided wind tunnels

The method chosen to compensate for the forces acting on the barrel in the course of compression and confinement of the test gas in the settling chamber of a hypersonic wind tunnel with a free locking piston is justified. A method is proposed to compensate for the effect of adverse factors by optimizing the mass of an auxiliary piston introduced into the system. The effectiveness of the method is validated experimentally. As a result, for the case of gas compression to 200 MPa, the displacement of the center of mass of the barrel is reduced from 50 to 0.25 mm, which is smaller than the amplitude of elastic axial extension corresponding to the maximum pressure of the gas. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 5, pp. 212–220, September–October, 2008.