CN113820138A - Engine ground test environment control system - Google Patents
Engine ground test environment control system Download PDFInfo
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- CN113820138A CN113820138A CN202111184377.3A CN202111184377A CN113820138A CN 113820138 A CN113820138 A CN 113820138A CN 202111184377 A CN202111184377 A CN 202111184377A CN 113820138 A CN113820138 A CN 113820138A
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- 238000012360 testing method Methods 0.000 title claims abstract description 18
- 238000009413 insulation Methods 0.000 claims abstract description 31
- 238000010521 absorption reaction Methods 0.000 claims abstract description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 22
- 230000003584 silencer Effects 0.000 claims abstract description 20
- 239000007921 spray Substances 0.000 claims abstract description 17
- 238000005507 spraying Methods 0.000 claims abstract description 14
- 230000004888 barrier function Effects 0.000 claims abstract description 13
- 239000007789 gas Substances 0.000 claims description 15
- 229910000831 Steel Inorganic materials 0.000 claims description 12
- 239000010959 steel Substances 0.000 claims description 12
- 238000002347 injection Methods 0.000 claims description 9
- 239000007924 injection Substances 0.000 claims description 9
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 239000002184 metal Substances 0.000 claims description 8
- 230000030279 gene silencing Effects 0.000 claims description 6
- 239000002737 fuel gas Substances 0.000 claims description 2
- 238000003466 welding Methods 0.000 claims description 2
- 239000003344 environmental pollutant Substances 0.000 abstract description 4
- 231100000719 pollutant Toxicity 0.000 abstract description 4
- 238000001816 cooling Methods 0.000 abstract description 3
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 230000003993 interaction Effects 0.000 abstract description 2
- 230000002093 peripheral effect Effects 0.000 abstract description 2
- 230000009467 reduction Effects 0.000 description 10
- 238000000034 method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 241000357293 Leptobrama muelleri Species 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/14—Testing gas-turbine engines or jet-propulsion engines
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/02—Details or accessories of testing apparatus
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Testing Of Engines (AREA)
- Exhaust Silencers (AREA)
Abstract
An engine ground test environmental control system utilizes an exhaust guide cylinder, an exhaust muffler, a peripheral sound-proof wall and a spray device to reduce and isolate noise and pollution of engine exhaust. When the engine is tested, high-temperature engine exhaust is sprayed into the exhaust guide cylinder, sound energy is reduced by spraying and cooling, and pollutants in the exhaust are dissolved in water; the sound absorption structures of the exhaust guide cylinder and the silencer further absorb sound energy of exhaust gas; the longer guiding and injecting cylinder and the silencer isolate the direct interaction between the exhaust of the engine and the atmospheric environment, not only prevent the noise from diffusing, but also facilitate the pollutant in the exhaust to be dissolved in water; after the engine exhaust is sprayed out of the silencer, the temperature is further reduced, the noise is reduced, the pollution is reduced by the spraying system at the upper part of the sound insulation door and the sound barrier, and the noise and the pollution level are further reduced. The invention comprehensively utilizes various measures to reduce the pneumatic noise and pollution of the engine exhaust, and has the advantages of simple technical scheme, suitability for engines with different thrust forces and low system cost.
Description
Technical Field
The invention belongs to the technical field of aerospace, relates to a control technology of an engine ground test environment, and particularly relates to a device for reducing noise and exhaust pollution in a test process.
Background
In the development process of jet engines for aircrafts, ground testing of jet engines is an essential link. Since jet engines generate a great deal of noise when they are operating, it is important to reduce their noise for protection of personnel and to reduce environmental impact.
The jet engine is usually horizontally placed when in ground test run, and can be strongly mixed with the surrounding atmosphere to form pneumatic noise due to high jet speed even reaching supersonic speed. Aiming at noise reduction of a jet engine ground test, a water spray noise reduction scheme is mainly adopted. The united states landley test center firstly applies water spray noise reduction to the jet flow noise control field of an aviation jet aircraft engine at the end of the 50 th century in 20, and also applies to the water spray cooling noise reduction field of launch of a launch vehicle in the early 60 th century, and the main scheme is to arrange a water spray system at the entrance and the exit of a diversion facility. In the early 70 s of the 20 th century, the Soviet Union began to research and utilize water spray to reduce temperature and reduce noise to reduce jet noise and energy when the carrier rocket is launched and protect launching equipment and facilities. Similarly, for the work of large rocket engines, water spraying systems are arranged near the diversion trenches and on the launching cradle in China to spray a large amount of water to the tail flames of the rocket engines so as to achieve the purposes of protecting launching facilities and inhibiting strong noise of launching jet flow, and the prior patent in the aspect is as in CN201811271755.X (application number). However, these water spray noise reduction schemes are mainly aimed at the launching of large-scale vehicles, and for daily ground test runs of jet engines, the existing noise reduction methods have limited effect. For example, CN202010624707.5 (application number) is to add a straight sleeve outside an engine nozzle, and spray water in the sleeve and at the outer edge of the sleeve outlet to form a water curtain for isolation and noise reduction, which still has a great influence on the surrounding human environment during engine test.
Disclosure of Invention
The invention provides a control method and a control device capable of reducing engine test noise and exhaust emission, which realize the aim by means of multi-stage measure step-by-step treatment and comprehensive treatment measure paralleling, and have the characteristics of good noise and pollution reduction effect and easy implementation.
The technical scheme of the invention is as follows:
an engine ground test environment control system comprises a support 2, an exhaust ejector sleeve 3, an exhaust silencer 4, a spray pipeline 5, a water pump 6, a sound absorption and insulation barrier and a steel sound insulation door 9;
the support 2 is used for fixing the exhaust gas guiding and jetting cylinder 3, and the bottom of the support is provided with a movable wheel which is fixedly connected with the ground through an expansion bolt;
the front section of the exhaust gas guiding and jetting cylinder 3 is conical, the rear section of the exhaust gas guiding and jetting cylinder is cylindrical, and the exhaust gas guiding and jetting cylinder is a hollow structure formed by welding and combining an outer wall plate and an inner wall plate; wherein the inner wall plate is a micro-perforated sound absorption structure, namely a plurality of micro-holes are drilled on the inner wall plate, the aperture of each micro-hole is phi 0.5-phi 1mm, and the perforation rate is 1% -3%; a cavity is reserved between the two layers of wall plates to form a sound absorption structure of the micro-perforated plate;
the exhaust muffler 4 is connected with the exhaust ejector cylinder 3 and is selected according to the thrust of the jet engine; for an engine with the thrust below 500N, a cuboid silencer with a built-in silencing plate is adopted, wherein the silencing plate is uniformly distributed in a longitudinal and transverse mode; for the trial run of an engine with the thrust of more than 500N, the silencer is of a downward inclined cylindrical structure, the included angle between the silencer and the horizontal direction is 10-15 degrees, and the exhaust direction is inclined to the ground; the downward inclined cylindrical silencer adopts a sound absorption structure of a double-layer micro-perforated plate which is the same as the exhaust ejector cylinder 3;
the sound absorption and insulation barrier mainly comprises a transparent sound insulation plate 7 arranged in the middle in the horizontal direction and upper and lower metal sound absorption and insulation plates 8, and is fixedly connected with a steel sound insulation door 9 through a hinge 10 and a steel upright post framework 11, and the sound absorption and insulation barrier and the steel sound insulation door 9 are arranged on two sides and at the rear of the exhaust ejector cylinder 3 and the exhaust silencer 4; the sound absorption and insulation barriers at two sides are fixed on the outer wall of the test room;
the spraying pipeline 5 is divided into two paths, one path enters the conical section of the exhaust injection cylinder 3 and sprays fuel gas in the exhaust injection cylinder 3, and the other path is arranged at the upper part of the sound absorption and insulation barrier and sprays tail gas exhausted from the exhaust silencer 4; the water for spraying is pressurized by a water pump 6.
The principle of the invention is as follows: (1) when the engine is tested, high-temperature tail flame is sprayed into the exhaust gas guide cylinder, sound energy is reduced by spraying and cooling at the front end, and pollutants in the exhaust gas are dissolved in water; (2) the sound absorption structures of the exhaust guide cylinder and the exhaust silencer further absorb sound energy of exhaust gas; (3) the longer guiding and injecting cylinder and the silencer isolate the direct interaction between the exhaust of the engine and the atmospheric environment, not only prevent the noise from diffusing, but also facilitate the pollutant in the exhaust to be dissolved in water; (4) after the engine exhaust is sprayed out of the silencer, the temperature is further reduced, the noise is reduced, the pollution is reduced by the spraying system at the upper part of the sound insulation door and the sound barrier, and the noise and the pollution level are further reduced.
The invention has the advantages of comprehensively utilizing the multilevel measures of noise reduction and pollution reduction of the inner and peripheral sound barriers of the spraying and exhaust ejector cylinder, realizing the effective control of the exhaust environment of the jet engine, having simple technical scheme, being suitable for engines with different thrusts and having low system cost.
Drawings
FIG. 1 is a schematic diagram of an engine ground test environmental control system.
Fig. 2 is a schematic view of an exhaust muffler suitable for low thrust, (a) an external view, and (b) an internal view.
Fig. 3 is a schematic of an exhaust muffler suitable for moderate thrust.
In the figure: 1, an engine nozzle; 2, a bracket; 3 an exhaust gas guiding and injecting cylinder; 4, an exhaust muffler; 5, a spraying pipeline; 6, a water pump; 7, a transparent sound insulation plate; 8, a metal sound absorption and insulation plate; 9, a steel soundproof door; 10, a hinge; 11 steel upright column framework.
Detailed Description
The following detailed description of the embodiments of the invention is provided in connection with the accompanying drawings.
Example 1:
an environment control system is designed for the ground test bed of the liquid rocket engine with the thrust of 300N and 3000N.
(1) The structural dimensions of the exhaust gas guiding barrel 3 are: the diameter of the conical inlet end is 0.6m, the diameter of the outlet end is 1.2m, and the length is 1.5 m; the diameter of the cylindrical section of the injection cylinder is 1.2m, the length of the cylindrical section of the injection cylinder is 1.0m, and the cylindrical section of the injection cylinder is connected with the conical section through a flange.
(2) The exhaust muffler 4 of a 300N engine adopts a sheet type muffler, the size is 1.5m multiplied by 2m, the front end of the muffler is a round and square variable diameter, the length is 0.5m, and the muffler is connected with the injection cylinder 3. The internal silencing pieces are divided into a horizontal part and a vertical part, the lengths of the silencing pieces are all 0.75m, the thickness of each piece is 100mm, and the distance between the pieces is 100 mm.
(3) An exhaust muffler for a 3000N engine adopts a downward inclined muffling barrel, the diameter of the inlet end of the muffling barrel is 1.2m, the length of the muffling barrel is 2.0m, the muffling barrel is inclined downward by 12 degrees and is connected with an exhaust injection barrel 3 through a flange.
(4) The metal sound absorption and insulation board and the sound insulation door are of composite structures, and are respectively a 304H stainless steel perforated panel with the thickness of 1.0mm, a high-temperature sound absorption foamed ceramic with the thickness of 100mm, sound absorption through hole foamed aluminum (wrapped by hydrophobic glass fiber cloth) with the thickness of 8mm and a 304H stainless steel back plate with the thickness of 1.0mm from one side facing an engine.
(5) The metal sound absorption and insulation plate is fixed in an insertion mode and is installed inside flange notches on two sides of the H-shaped steel, and a bottom plate is welded at the bottom of the H-shaped steel and is connected with the ground in an anchor bolt mode.
(6) The metal sound absorption and insulation plates on the two sides are 6 meters long and 3.5 meters high, and a lighting sound insulation window 0.5 meter high is arranged at the 1.5-2 meter high position of the metal sound absorption and insulation plates on the two sides, so that the condition of the test bed can be observed conveniently.
(7) The top of the metal sound absorption and insulation plate is provided with spray openings, and each spray opening is separated by 0.5 meter and distributed at equal intervals. The spraying angle of each spraying opening is 45 degrees with the axis, and the water spraying flow is 150 g/s.
Claims (1)
1. The ground test environment control system of the engine is characterized by comprising a support (2), an exhaust ejector cylinder (3), an exhaust silencer (4), a spray pipeline (5), a water pump (6), a sound absorption and insulation barrier and a steel sound insulation door (9);
the support (2) is used for fixing the exhaust gas guiding and jetting cylinder (3), and the bottom of the support is provided with a movable wheel which is fixedly connected with the ground through an expansion bolt;
the front section of the exhaust gas guiding and jetting cylinder (3) is conical, the rear section of the exhaust gas guiding and jetting cylinder is cylindrical, and the exhaust gas guiding and jetting cylinder is a hollow structure formed by welding and combining an outer wall plate and an inner wall plate; wherein the inner wall plate is a micro-perforated sound absorption structure, namely a plurality of micro-holes are drilled on the inner wall plate, the aperture of each micro-hole is phi 0.5-phi 1mm, and the perforation rate is 1% -3%; a cavity is reserved between the two layers of wall plates to form a sound absorption structure of the micro-perforated plate;
the exhaust muffler (4) is connected with the exhaust guide cylinder (3) and is selected according to the thrust of the jet engine; for an engine with the thrust below 500N, a cuboid silencer with a built-in silencing plate is adopted, wherein the silencing plate is uniformly distributed in a longitudinal and transverse mode; for the trial run of an engine with the thrust of more than 500N, the silencer is of a downward inclined cylindrical structure, the included angle between the silencer and the horizontal direction is 10-15 degrees, and the exhaust direction is inclined to the ground; the downward inclined cylindrical silencer adopts a sound absorption structure of a double-layer micro-perforated plate which is the same as the exhaust guide cylinder (3);
the sound absorption and insulation barrier mainly comprises a transparent sound insulation plate (7) arranged in the middle in the horizontal direction and upper and lower metal sound absorption and insulation plates (8), and is fixedly connected with a steel sound insulation door (9) through a hinge (10) and a steel upright post framework (11), and the sound absorption and insulation barrier and the steel sound insulation door (9) are arranged on the two sides and the rear of the exhaust ejector cylinder (3) and the exhaust silencer (4); the sound absorption and insulation barriers at two sides are fixed on the outer wall of the test room;
the spraying pipeline (5) is divided into two paths, one path enters the conical section of the exhaust injection cylinder (3) and sprays fuel gas in the exhaust injection cylinder (3), and the other path is arranged at the upper part of the sound absorption and insulation barrier and sprays tail gas exhausted from the exhaust silencer (4); the water for spraying is pressurized by a water pump (6).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111184377.3A CN113820138A (en) | 2021-10-11 | 2021-10-11 | Engine ground test environment control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111184377.3A CN113820138A (en) | 2021-10-11 | 2021-10-11 | Engine ground test environment control system |
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| Publication Number | Publication Date |
|---|---|
| CN113820138A true CN113820138A (en) | 2021-12-21 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111184377.3A Pending CN113820138A (en) | 2021-10-11 | 2021-10-11 | Engine ground test environment control system |
Country Status (1)
| Country | Link |
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| CN (1) | CN113820138A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114486269A (en) * | 2022-04-15 | 2022-05-13 | 中国飞机强度研究所 | Engine driving temperature control system for aircraft testing laboratory and design method thereof |
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| US5706651A (en) * | 1995-08-29 | 1998-01-13 | Burbank Aeronautical Corporation Ii | Turbofan engine with reduced noise |
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| CN200975275Y (en) * | 2006-08-18 | 2007-11-14 | 姜建波 | combination type exhausting silencer for gas engine |
| CN101288826A (en) * | 2007-04-22 | 2008-10-22 | 冯云善 | Oil engine discharging tail gas filtering and cleaning technique |
| CN103743572A (en) * | 2014-01-08 | 2014-04-23 | 北京航空航天大学 | Small-sized rocket engine test bed spray device |
| CN204114450U (en) * | 2014-09-10 | 2015-01-21 | 冯奕炜 | A kind of grating type pipeline silencer |
| CN105067247A (en) * | 2015-08-15 | 2015-11-18 | 杰锋汽车动力系统股份有限公司 | Engine exhaust silencer hot-cold impact test device and test method utilizing the same |
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2021
- 2021-10-11 CN CN202111184377.3A patent/CN113820138A/en active Pending
Patent Citations (11)
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114486269A (en) * | 2022-04-15 | 2022-05-13 | 中国飞机强度研究所 | Engine driving temperature control system for aircraft testing laboratory and design method thereof |
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