A method to effectively prolong the flow time of a large-scale free piston high-enthalpy pulsed wind tunnel

Abstract

The method for effectively prolonging the flow time of a large-scale free-piston high-enthalpy pulsed wind tunnel involves the technical field of wind tunnel testing; it includes the following steps: step 1, dividing the nozzle configuration into a contraction section AT and an expansion section TF in the axial direction; the contraction section AT and the expansion section TF are connected along the axial direction; the intersection point T is the position of the throat; the position of the throat T is determined; step 2, based on the throat T, the expansion section TF is divided into the first segment TC and the second segment CE and the third segment EF; respectively design the pipeline configurations of the first segment TC, the second segment CE and the third segment EF; step 3, taking the throat T as the benchmark, divide the contraction segment AT into contraction The front section AB and the contraction rear section BT; the pipeline configurations of the contraction front section AB and the contraction rear section BT are respectively designed; the invention effectively prolongs the running time of the wind tunnel flow field; at the same time, the operating state of the wind tunnel can be adjusted by changing the inner diameter of the throat , It is also convenient to replace parts that are partially ablated in the throat due to high temperature.

Description

technical field [0001] The invention relates to the technical field of wind tunnel tests, in particular to a method for effectively prolonging the flow time of a large-scale free piston high-enthalpy pulse wind tunnel. Background technique [0002] The large-scale free-piston high-enthalpy pulsed wind tunnel is one of the main ground simulation devices for studying high-temperature real gas effects, and it has the ability to simulate ultra-high-speed flow. Under the condition of ultra-high-speed flow, the free flow at the nozzle outlet has a scale effect. In order to reduce the influence of the absolute size of the nozzle on the free flow, the size of the nozzle needs to be large enough, and the corresponding size of the shock tube and the size of the compression tube are also large. For large-scale free-piston high-enthalpy pulsed wind tunnels, due to the large inner diameter of the shock tube, after the rupture of the diaphragm of the main clamping mechanism, the accelera...

AI Technical Summary

Problems solved by technology

For large-scale free-piston high-enthalpy pulsed wind tunnels, due to the large inner diameter of the shock tube, after the rupture of the diaphragm of the main clamping mechanism, the acceleration of the free piston at the end of the compression tube is too fast, causing safety hazards to the piston and the wind tunnel. Hidden dangers, while reducing the constant pressure driving time of the compression tube, the test time of the wind tunnel is too short, which affects the test capability of the wind tunnel

At present, there is no relevant technology to effectively solve the wind tunnel test capability

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