An exhaust device for the exhaust simulation test of a supersonic engine tail nozzle

Abstract

The invention discloses an air exhaust device for an ultrasonic engine jet pipe exhaust simulation experiment. The air exhaust device comprises a tail chamber, an injector and a two-stage injector. The tail chamber comprises a fixed large tail chamber and a replaceable small tail chamber. The fixed large tail chamber comprises a tail chamber convergent segment, a tail chamber equal-diameter segment and a tail chamber expanding segment. The replaceable small tail chamber comprises a small tail chamber flange and a small tail chamber cylinder. The small tail chamber cylinder is arranged in the tail chamber convergent segment. The fixed large tail chamber is provided with a circulated cooling water device and a cooling water spraying device. The injector comprises a low-pressure chamber, a transition segment, a blending convergent segment, a blending equal-diameter segment and a blending expanding segment. The low-pressure chamber is internally and fixedly connected with an annular shunting flow guiding device, an injected air current conveying pipe, an injected air current convergent segment and an injected air current expanding segment. The outlet of the low-pressure chamber and the outlet cross section of the injected air current expanding segment are in the same vertical plane. The air exhaust device can satisfy an experiment requirement for simulating high-altitude flight states of different ultrasonic engines on ground.

Description

technical field [0001] The invention relates to an exhaust device, in particular to an exhaust device for a supersonic engine tail nozzle exhaust simulation test. Background technique [0002] When simulating the high-altitude flight state of a supersonic engine on the ground, the engine is usually installed in the high-altitude simulation cabin first, and the high-altitude cabin is pumped with air extraction equipment so that the pressure in the high-altitude simulation cabin is the same as the environment where the engine is flying at high altitude. The pressure is the same, and then the engine is ignited, and the high-altitude flight simulation test is carried out. During the test, the pressure in the high-altitude simulation cabin must always be kept the same as the ambient pressure at the altitude of the engine when it is flying at high altitude. The gas is discharged from the high-altitude simulation cabin. In the prior art, an ejector or a vacuum tank is usually used ...

AI Technical Summary

Problems solved by technology

[0002] When simulating the high-altitude flight state of a supersonic engine on the ground, the engine is usually installed in the high-altitude simulation cabin first, and the high-altitude cabin is pumped with air extraction equipment so that the pressure in the high-altitude simulation cabin is the same as the environment where the engine is flying at high altitude. The pressure is the same, and then the engine is ignited, and the high-altitude flight simulation test is carried out. During the test, the pressure in the high-altitude simulation cabin must always be kept the same as the ambient pressure at the altitude of the engine when it is flying at high altitude. The gas is discharged from the high-altitude simulation cabin. In the prior art, an ejector or a vacuum tank is usually used for pumping air, and the pressure outside the high-altitude simulation cabin is usually 0.11MPa, while the ambient pressure at the flying height of the supersonic engine is only about 100% of the atmospheric pressure. 0.1 times, or even 0.01 times, the boost ratio of the exhaust system should reach 10 to 100, and the flow rate of the corresponding exhaust system inlet is as high as ten kilograms or even hundreds of kilograms per second. The flow rate depends only on the pressurization of the ejector, and three to four stages must be connected in series. If a vacuum tank is used, the volume of the vacuum tank must be as high as tens of thousands of cubic meters. It can be seen that no matter whether the ejector or the vacuum tank is used alone as the pumping Air equipment requires a huge structure, which is not only inefficient, but also very expensive; secondly, the engine test bench usually needs to perform high-altitude flight simulation for various engines, and different engines, engine size, engine tail nozzle size, engine The outlet flows are all different, and a set of air extraction equipment cannot meet the test requirements of various engines; No pressure) of the ejected airflow, the device that completes the ejected airflow and sucks the ejected airflow for mixing injection or delivery. Since the ejector has no moving parts, it is reliable and widely used in the exhaust system of the engine test bench; and The geometrical and positional relationship of the ejector that provides the ejector airflow and the blender of the blender is the key factor that determines the performance of the ejector. In the prior art, for the ejector of the exhaust system of the engine test bench, A mature and reasonable geometric and positional relationship between the ejecting part and the mixing part has not been formed, resulting in low ejecting performance of the ejector, reducing the efficiency of the test, and increasing the cost of the test; in addition, the high-altitude flight The gas discharged from the engine is a high-temperature gas, and its temperature is usually above 350°C. When the high-temperature gas discharged from the engine flows inside the metal pipe, due to the property of metal thermal expansion and contraction, the pipe will expand axially. When the high-temperature medium flows Afterwards, as the metal pipe returns to normal temperature, the metal pipe will be shortened to its original length. The existing pipe support cannot absorb the axial length change of the metal pipe due to thermal expansion and contraction, which will cause the pipe support to deform or even break. The fixed connection of the high-altitude simulation cabin will also be deformed or even broken

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