METHOD FOR INCREASING THE WORKING TIME OF A SHOCK TUBE AND A DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2023 - IPC G01M9/00 

FIELD: aerodynamics.

SUBSTANCE: invention relates to the field of experimental aerodynamics and can be used to obtain a high-speed gas flow with large Mach numbers in laboratory conditions in non-diaphragm shock tubes of short-term action. The method consists in the fact that the gas under pressure flows from the high-pressure chamber into the low-pressure chamber due to the evacuating of air, which presses the movable cap of the pneumatic valve. The air is evacuated into the additional cavity through an opening connected to the valve and remains there under the spring-loaded lid until the pressure of the pressurizing air in the additional cavity becomes greater than the pressure of the expansion fan in the high-pressure chamber. In this case, the lid is squeezed out of the hole facing the high-pressure chamber, and the evacuated air enters the high-pressure chamber, and the additional cavity has an initial pressure of no more than 1 atm. The device contains a high-pressure chamber connected in series, a means of closing the channel in the form of a pneumatic valve with a movable cap due to the pressurizing air, and a low-pressure chamber. The pneumatic valve has an additional cavity adjacent to the valve, facing towards the high-pressure chamber, with two openings, one of them connected to the valve and the other to the high-pressure chamber, closed by a spring-loaded lid, which is closed at the initial moment.

EFFECT: increase in the working time of the shock tube due to the deceleration of the rarefaction wave.

2 cl, 1 dwg