Shock tube electric needle piercing and membrane rupturing device capable of being used under low pressure conditions

Abstract

The invention relates to the technical field of combustion experiments, and aims to provide a shock tube electric needle piercing and membrane rupturing device capable of being used under low pressureconditions. The shock tube electric needle piercing and membrane rupturing device comprises a micro motor, wherein the micro motor is fixedly mounted on the inner wall of a shock tube by means of a motor base, a motor screw is parallel to the axis of the shock tube and has threads; a hollow tubular needle piercing sleeve has an opening end and a closed tail end, and a piercing needle is mounted at the tail end; the needle piercing sleeve is internally provided with threads or a rack in the length direction of the needle piercing sleeve, the needle piercing sleeve sleeves the motor screw fromthe opening end and drives the threads or the rack to be engaged with the threads of the motor screw; and the outer side of the needle piercing sleeve is provided with a transverse protruding portionhaving a through hole, a guide rod parallel to the needle piercing sleeve passes through the through hole, and one end of the guide rod is fixed on the micro motor. According to the shock tube electric needle piercing and membrane rupturing device, the needle withdrawing speed of the piercing needle is faster and more uniform than that of an ordinary mechanical needle piercing and membrane rupturing mechanism by adopting electric control, the precise time of membrane rupturing is easier to control, the piercing needle is convenient to replace, easy to seal and high in universal performance, and the shock tube electric needle piercing and membrane rupturing device can be well used under the low pressure conditions, is reliable and efficient and has good repeatability.

Description

technical field [0001] The invention belongs to the technical field of combustion experiments, and relates to a shock tube electric needle piercing membrane device that can be used under low pressure conditions. Background technique [0002] Hydrocarbon fuel has a wide range of sources and high energy density. It is also the most widely used fuel for aviation aircraft. The ignition characteristics of hydrocarbon fuel are related to the energy release law of fuel and the study of combustion dynamics. It is one of the hot spots in aero-engine research and other related fields. . Ignition delay time is an important characterization of the combustion characteristics of hydrocarbon fuels, and it is also an important basis for verifying the chemical kinetic model and simplified model of combustion reaction. In practical engineering applications, the ignition delay time of the fuel is one of the important parameters in the design of the scramjet engine and pulse detonation engine ...

AI Technical Summary

Problems solved by technology

Especially under low-pressure reaction conditions, because the pressure difference between the high and low pressure ends of the shock tube is small, it increases the difficulty of membrane rupture and reduces the success rate of membrane rupture, and requires external force to rupture the membrane. Therefore, for low-pressure environments In the shock tube experiment, it is very important to select the appropriate membrane rupture device and method

[0005] The problems existing in the existing membrane rupture devices are: (1) The efficiency of electrothermal membrane rupture is not high, and there is a high probability that the membrane cannot be ruptured.

(2) It is difficult to accurately control the rupture pressure by using high-pressure independent membrane rupture, and it is impossible to accurately control the experimental working conditions

(3) The speed of traditional needle piercing to break the membrane is not high. When the pressure of the driving section of the shock tube is relatively high, the sealing problem of the driving section and the acupuncture speed will affect the quality of the airflow and the consistency of the shock wave velocity.

Images