Cold air thrust testing device for attitude and orbit control engine
Technical Field
The invention relates to a device for reducing air inlet interference in a cold air thrust test of an attitude and orbit control engine, which can reduce air inlet interference, in particular to reduce air inlet interference in the cold air thrust test of the engine.
Background
At present, systems such as spacecrafts, missile weapons and the like adopt attitude and track adjusting devices to realize pitching, yawing, rolling and other movements. The conventional ground hot test has long test period and high cost, and is difficult to comprehensively collect the performance data of the engine. The cold air test is an effective means for improving the performance verification efficiency of the engine and shortening the development process. The thrust output characteristic of the engine is very important for the control system, and as the cold air source flows through the pipeline to be connected to the combustion chamber, the measurement precision of the thrust is reduced due to the interference of the pipeline on the measurement, and the measurement of the dynamic characteristic is more difficult.
The conventional engine thrust measurement mainly adopts an engine head to support a thrust sensor, and fuel gas generated by engine combustion flows out through a spray pipe to form reaction thrust, so that the engine thrust value is obtained. In the cold air test, the conventional scheme is difficult to apply due to the introduction of the air inlet pipeline, and in the cold air thrust measurement test, air inlet interference is mainly shown in the following aspects:
(1) the cold air inlet pipeline is connected with the engine combustion chamber, high-pressure inlet air generates interference force, and the interference force and thrust generated by the spray pipe are superposed on the thrust sensor;
(2) the high-pressure gas with different pressures causes inconsistent influence of the pipeline on the measurement system.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: overcome prior art's not enough, a device that air conditioning thrust test that is used for attitude and orbit accuse engine reduces interference of admitting air is proposed, aim at solves the not enough in the current engine air conditioning thrust measurement technique, this structure can reduce the interference of air inlet pipeline to thrust measurement, promote engine thrust measurement accuracy, through 180 subtend double-circuit air inlet structure, the influence of the impact of admitting air has been reduced, through the design of moving-quiet fixed knot structure, realize the decoupling separation with the thrust that the interference force that the air inlet pipeline produced and spray tube produced, effectively reduce the interference that the air inlet pipeline was measured engine air conditioning thrust.
The technical solution of the invention is as follows:
a device for reducing air inlet interference in a cold air thrust test of an attitude and orbit control engine comprises a base, a first air inlet pipeline, a second air inlet pipeline, an air outlet pipeline, a first air inlet pipeline adapter, a second air inlet pipeline adapter, an air outlet pipeline adapter and a bearing, wherein the first air inlet pipeline is connected with the base through the second air inlet pipeline;
the first air inlet pipeline, the second air inlet pipeline, the air outlet pipeline, the first air inlet pipeline adapter, the second air inlet pipeline adapter, the air outlet pipeline adapter and the bearing are all arranged on the base;
one end of the first air inlet pipeline is used for introducing cold air, and the other end of the first air inlet pipeline is fixedly connected with the bearing through a first air inlet pipeline adapter;
one end of the second air inlet pipeline is used for introducing cold air, and the other end of the second air inlet pipeline is fixedly connected with the bearing through a second air inlet pipeline adapter;
one end of the air outlet pipeline is movably connected with the bearing through an air outlet pipeline adapter, the air outlet pipeline can rotate around the bearing, and the other end of the air outlet pipeline is connected with a combustion chamber of the attitude and orbit control engine and used for discharging cold air into the combustion chamber;
the central axis of the first air inlet pipeline is superposed with the central axis of the second air inlet pipeline;
the central axis of the first air inlet pipeline or the central axis of the second air inlet pipeline is vertical to the central axis of the air outlet pipeline;
the first air inlet pipeline and the second air inlet pipeline are used for enabling cold air to be in an opposite air inlet state of 180 degrees, and the influence of air inlet on thrust measurement is reduced.
Compared with the prior art, the invention has the following remarkable advantages:
(1) the invention designs a 180-degree opposite double-pipeline air inlet structure, reduces the influence of the air inlet direction on thrust measurement, designs a movable-static frame connecting structure, adopts the separated design of an air inlet structure and an air outlet structure, and is connected through a bearing, so that the axial interference force generated by an air inlet pipeline cannot be transmitted to a thrust measurement system, and the interference of the air inlet pipeline on the thrust measurement is reduced; meanwhile, the influence of cold air incoming flow with different pressures on the thrust measurement is eliminated, and the cold air test thrust measurement precision is effectively improved.
(2) The first air inlet pipeline, the second air inlet pipeline, the air outlet pipeline and the bearing form a dynamic-static frame structure, the thrust axis direction of the spray pipe is perpendicular to the axis direction of the air inlet pipeline, the axial force generated by the air inlet pipeline cannot be transmitted to the thrust measuring system, the air inlet pipeline and the measuring system are separated, and the influence of air inlet interference force is effectively reduced.
(3) The invention relates to a device for reducing air inlet interference in a cold air thrust test of an attitude and orbit control engine. The structure mainly comprises a base, an air inlet pipeline, an air outlet pipeline, an air inlet pipeline adapter, an air outlet pipeline adapter, a connecting bearing, a check ring and a sealing element. The structure for reducing the air intake interference mainly comprises the steps of selecting pipelines with corresponding diameters according to the flow required by an engine cold air thrust measurement test to ensure sufficient cold air flow, and simulating the thrust state under the actual gas state by using cold air. In the structure for integrally reducing the air inlet interference in the engine cold air thrust test, the bearing fixing mode can be selected and is not limited to use of a check ring, and the connection fixing mode of the air inlet pipeline adapter can be selected and is not limited to use of a screw. The invention can realize the decoupling separation of the air inlet interference force and the output force of the spray pipe, reduce the interference of the air inlet pipeline of the cold air and improve the measurement precision of the thrust of the cold air of the engine.
Drawings
FIG. 1 is a schematic diagram of the apparatus of the present invention, wherein 1-the base, 2-the first inlet line, 3-the inlet line adapter, 4-the bearing, 5-the outlet line adapter, 6-the outlet line, 7-the second inlet line, 8-the second inlet line adapter;
FIG. 2 shows engine thrust data results.
Detailed Description
The invention is further illustrated by the following figures and examples.
Firstly, the bearing is connected with the first air inlet pipeline adapter, the bearing is installed in place on the basis of the positioning step surface of the air inlet pipeline adapter, and the end surface of the inner ring of the bearing is attached to the positioning surface to realize positioning installation. The first air inlet pipeline adapter is connected with a bearing retainer ring, the retainer ring is arranged in a retainer ring clamping groove formed in the machining process of the air inlet pipeline adapter, and the end face of the retainer ring is in contact with the inner ring of the bearing, so that the position of the bearing is fixed.
Secondly, the air inlet pipeline adapter is connected with a sealing element, and the sealing element is installed in a sealing groove of the air inlet pipeline adapter. And repeating the installation process, and installing two symmetrical sets to complete the connection of the bearing and the second air inlet pipeline adapter.
And then, the first air inlet pipeline adapter and the second air inlet pipeline adapter are arranged on two sides of the air outlet pipeline adapter, the positioning surface of the air outlet pipeline adapter is taken as a reference, the end surface of the connecting bearing is attached to the positioning surface of the air outlet pipeline adapter, and the sealing element is attached to the sealing surface of the air outlet pipeline adapter, so that reliable sealing is ensured. The air inlet pipeline adapter is connected with the base and fixedly connected with the base through screws. And finally, connecting the first air inlet pipeline, the second air inlet pipeline and the air outlet pipeline with the first air inlet pipeline adapter, the second air inlet adapter and the air outlet pipeline adapter respectively.
The device for reducing air inlet interference for the attitude and orbit control engine cold air thrust test is mounted, a connecting bearing is fixed by a retainer ring in a schematic diagram, an air inlet pipeline adapter is connected with a mechanical fixing device by screws, and the connecting and fixing structure in the invention is not limited to the structure. According to different cold air flows and different pipeline calibers, different connection modes can be selected to meet the requirements of different flow cold air thrust measurement tests.
Examples
Referring to fig. 1, a device for reducing intake interference for cold air thrust test of a posture and orbit control engine includes a base 1, a first intake pipeline 2, a second intake pipe 7, an exhaust pipeline 6, a first intake pipeline adapter 3, a second intake pipeline adapter 8, an exhaust pipeline adapter 5 and a bearing 4;
the first air inlet pipeline, the second air inlet pipeline, the air outlet pipeline, the first air inlet pipeline adapter, the second air inlet pipeline adapter, the air outlet pipeline adapter and the bearing are all arranged on the base;
one end of the first air inlet pipeline is used for introducing cold air, and the other end of the first air inlet pipeline is fixedly connected with the bearing through a first air inlet pipeline adapter;
one end of the second air inlet pipeline is used for introducing cold air, and the other end of the second air inlet pipeline is fixedly connected with the bearing through a second air inlet pipeline adapter;
one end of the air outlet pipeline is movably connected with the bearing through an air outlet pipeline adapter, the air outlet pipeline can rotate around the bearing, and the other end of the air outlet pipeline is connected with a combustion chamber of the attitude and orbit control engine and used for discharging cold air into the combustion chamber;
the central axis of the first air inlet pipeline is superposed with the central axis of the second air inlet pipeline;
the central axis of the first air inlet pipeline or the central axis of the second air inlet pipeline is vertical to the central axis of the air outlet pipeline;
the first air inlet pipeline and the second air inlet pipeline are used for enabling cold air to be in an opposite air inlet state of 180 degrees, and the influence of air inlet on thrust measurement is reduced.
The attitude and orbit control engine cold air thrust test is carried out by utilizing the structure of the invention to obtain the engine thrust data result, as shown in figure 2, the thrust data is stable and is better matched with the design state, which shows that the attitude and orbit control engine cold air thrust test device can realize the accurate test of the attitude and orbit control cold air thrust.