CN110940525A - Blending device of multi-strand high-temperature hot gas and cold air for engine test bed - Google Patents

Blending device of multi-strand high-temperature hot gas and cold air for engine test bed Download PDF

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Publication number
CN110940525A
CN110940525A CN201911370955.5A CN201911370955A CN110940525A CN 110940525 A CN110940525 A CN 110940525A CN 201911370955 A CN201911370955 A CN 201911370955A CN 110940525 A CN110940525 A CN 110940525A
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China
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cold air
blending
cavity
holes
mixing
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易欢
石运军
黄炳修
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Gloomy Wind-Tunnel Engineering Of Beijing Space Flight Benefit Co Ltd
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Gloomy Wind-Tunnel Engineering Of Beijing Space Flight Benefit Co Ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M15/00Testing of engines
    • G01M15/02Details or accessories of testing apparatus

Abstract

The invention discloses a multi-strand mixing device of high-temperature hot gas and cold air for an engine test bed, which comprises a cold air cavity, a mixing section inner cavity and a steady flow section which are coaxially arranged, wherein the mixing section inner cavity is formed by sequentially connecting an expansion section, an equal straight section and a contraction section, the front end of the mixing section inner cavity is provided with a steering flat plate for plugging an inlet of the expansion section, and the rear end of the mixing section inner cavity is connected with the steady flow section; the cold air cavity is formed by sealing and wrapping the inner cavity of the blending section through the outer shell, a plurality of high-temperature hot air inlets are uniformly arranged on the side wall, close to the front end, of the inner cavity of the blending section in the circumferential direction, and a plurality of cold air inlets are uniformly arranged on the side wall, close to the front end, of the outer shell in the circumferential direction; arranging a plurality of cold air anti-steering holes on the steering flat plate; the expansion section is provided with a plurality of cold air flow stabilizing holes, the equal straight section is provided with a plurality of cold air mixing holes, and the contraction section is provided with a plurality of cold air blow-off holes; the steady flow section comprises a short equal straight section and a contraction section. The invention is suitable for large-flow test bed.

Description

Blending device of multi-strand high-temperature hot gas and cold air for engine test bed
Technical Field
The invention relates to a blending device of multi-strand high-temperature hot air and cold air for an engine test bed.
Background
With the development of hypersonic aircraft technology, a scramjet engine is the key technology to be solved firstly, and a new engine test technology needs a test bed with the capability of being closer to a pure air test medium so as to eliminate the influence of combustion products on engine test data or avoid the occurrence of wrong engine test results. This kind of test bed generally adopts the two-stage heating mode, and the pure air heater is adopted to the first grade, and the combustion heater oxygenating gas mode is generally adopted to the second grade to obtain the test medium that is closer to pure and clean air, the test air current that lower combustion product quality accounts for the ratio promptly, and through mixing device, accurate control air current temperature makes the air current even, satisfies different flow requirement engine test requirements.
Compared with the conventional engine test bed, the new engine test bed requires that the mass ratio of combustion products in the test medium is low enough, so that the temperature loss of the heated high-temperature test medium passing through the mixing device is small enough. Under the condition that the air heating capacity of the first-stage pure and clean air heater is limited, the temperature is generally lower than 700 ℃, if the temperature loss of the blending device behind the heater is increased, the increased temperature loss of the airflow behind the blending device can be overcome only by improving the heating capacity of the second-stage combustion heater and increasing the temperature of the airflow at the outlet of the heater, and the test airflow meeting the test requirement of the engine is obtained; meanwhile, the heating capacity of the second-stage combustion heater is improved, more fuel is required to be combusted, more heat energy is released, and the mass ratio of combustion products in the test airflow is improved. Therefore, new engine runs require a low temperature loss air flow blending device.
The novel engine test bed controls the combustion product ratio at a lower level, the temperature of the test airflow heated by the two-stage heater is lower than 1150 ℃, and the temperature of the test airflow passing through the mixing device can reach 1000 ℃ at most, so that the novel mixing device needs to meet the requirements of low temperature loss and airflow uniformity at the same time.
In the novel engine test bed, a large-sized engine test bed is necessary equipment for carrying out the whole engine test. The flow and the total energy of the test air flow are both large, under the condition that the heating power of a single set of two-stage heater is limited, a plurality of sets of two-stage heaters are required to be connected in parallel for heating to obtain a plurality of strands of high-temperature hot air, the plurality of strands of high-temperature hot air are mixed through a mixing device, cold air with a low flow ratio is mixed at the same time, the temperature of the test air flow is accurately controlled, the air flow is uniform, and the design requirement of a 30-80 kg/s novel engine test bed is met.
The defects of the prior art are as follows:
a. in the literature, "a high-temperature gas mixing device" the mixing device is a conventional engine test bed device, and in the test bed, high-temperature gas is obtained by obtaining the high-temperature gas through a primary combustion heater and supplementing oxygen, and then cold air is mixed through a mixer to obtain a test medium meeting requirements. The temperature of the combustion airflow of the incoming flow of the mixing device is up to 1000-1600 ℃, the temperature of the required test airflow is only 600 ℃, the mass ratio of the mixable cold air is very high, the cooling and heat insulation mode of the mixing device is not specially designed, and the temperature loss of the airflow is large after the mixing device is used. If being applied to novel engine test bed, along with the cold air flow accounts for the ratio and reduces, cold air mixing section heat protection structure must not satisfy the operation requirement.
b. The blending device in the literature 'high-reliability multi-blade cold and hot air flow blending turbulence device' is a conventional engine test bed device, can realize the blending of 1800K-magnitude high-temperature fuel gas with the flow of 5-20 kg/s and cold air with the flow of 3-50 kg/s, has high cold air mass ratio and large overall temperature loss, and cannot meet the use requirements of a novel test bed. The wall surface heat-proof mode is mainly that the heat-proof structure is directly realized by cold air. If being applied to novel engine test bed, along with the cold air flow rate ratio reduction, the cold air blending section must not satisfy the operation requirement.
c. In the conventional gas flow engine test bed mixing device, the mixing section usually adopts high-cold air to form air film cooling heat protection or adopts water cooling heat protection, the air flow uniform section adopts a water cooling structure to prevent heat, the temperature loss of high-temperature air flow of the structure is high, and the low-temperature loss test requirement of a 50-80 kg/s novel engine test bed cannot be met.
d. Compared with the blending device of single-stranded high-temperature hot air and cold air of the similar small-sized engine test bed, the scheme that the high-temperature hot air inlet and the cold air are blown into the blending cavity is more complex, the configuration design of the blending section has great difference, and the blending device of the single-stranded high-temperature hot air and the cold air is not suitable for the use requirement of the large-sized engine test bed.
Disclosure of Invention
According to the blending device for the engine test bed, disclosed by the invention, through a specific blending configuration design, the temperature loss of test airflow in the blending device is reduced, the requirements of low temperature loss and airflow uniformity of a 30-80 kg/novel engine test bed are met, and the test requirements of local test pieces of engines with different flow rates are met.
The invention relates to a blending device of multi-strand high-temperature hot air and cold air for an engine test bed, which comprises a cold air cavity, a blending section inner cavity and a steady flow section which are coaxially arranged, wherein the blending section inner cavity is formed by sequentially connecting an expansion section, an equal straight section and a contraction section, the front end of the blending section inner cavity is provided with a steering flat plate for plugging the inlet of the expansion section, and the rear end of the blending section inner cavity is connected with the steady flow section; the cold air cavity is formed by sealing and wrapping the inner cavity of the mixing section through an outer shell, a plurality of high-temperature hot air inlets are uniformly and circumferentially arranged on the side wall, close to the front end, of the inner cavity of the mixing section, each high-temperature hot air inlet penetrates through the outer shell to be connected with an air source, the central axis of each high-temperature hot air inlet is perpendicular to the axis, a plurality of cold air inlets are uniformly and circumferentially arranged on the side wall, close to the front end, of the outer shell, and the central axis of each cold air inlet is perpendicular to the axis; a plurality of cold air anti-steering holes are uniformly arranged on the steering flat plate circumferentially around the axis, and the axis of each cold air anti-steering hole is parallel to the axis; the expansion section is provided with a plurality of cold air stabilizing holes, the equal straight section is provided with a plurality of cold air mixing holes, and the contraction section is provided with a plurality of cold air blowing-off holes for blowing in cold air against airflow; the stationary flow section comprises a short equal straight section and a contraction section, a plurality of pressure regulating exhaust holes are formed in the side wall of the rear portion of the short equal straight section, and a pressure regulating valve and an exhaust cooling section are arranged on a pressure regulating pipeline connected with the pressure regulating exhaust holes.
Preferably, the high temperature hot gas inlets are arranged in 8 in a radial opposed manner.
Preferably, the number of the cold air inlets is 8 in a radial opposed manner.
Preferably, the steering flat plate is a circular plate with the diameter 0.5-0.6 times that of the equal straight section of the cavity in the blending section, the cold air anti-steering holes are formed in the steering flat plate into an inner circle and an outer circle, the inner circle is uniformly and circumferentially provided with 8 cold air anti-steering holes, the outer circle is uniformly and circumferentially provided with 16 cold air anti-steering holes, and the cold air anti-steering holes are provided with independent pipe walls and penetrate through the inner shell and the outer shell of the steering flat plate.
Preferably the steady flow hole of cold air is provided with two rows, and every row has evenly arranged 24 along circumference, and all porose axis extension lines all pass through the axis, and all with the contained angle of axis is 45, makes the cold air following current blow in the cavity in the blending section, the anti steady flow hole of cold air has independent pipe wall, runs through change the ectonexine casing of blending section expansion section.
Preferably, the cold air mixing holes are axially provided with 4 rows, each row is uniformly provided with 24 holes along the circumferential direction, and the cold air anti-mixing holes are provided with independent pipe walls and penetrate through the inner and outer shells of the rotating and mixing section equal straight section.
Preferably the cold air blow-off hole is provided with two rows, and every row has evenly arranged 24 holes along circumference, and all porose axis extension lines all pass through the axis, and all with the axis becomes 60 contained angles, makes the interior cavity of the contrary air current of cold air insufflate blending section, the anti blow-off hole of cold air has independent pipe wall, runs through change the interior outer shell of blending section shrink section.
Preferably, the diameter of the equal straight section of the cavity in the blending section is 1.3 times of that of the equal straight section of the steady flow section, the overall length of the cavity in the blending section is 2 times of that of the equal straight section, and the length of the equal straight section of the steady flow section is 3 times of that of the equal straight section.
Preferably, the number of the pressure-regulating exhaust holes is 8, the extension line of the hole axis is intersected and vertical to the axis, the air flow speed in the hole corresponding to the aperture is 60-100 m/s, and the maximum flow design requirement is 30 kg/s.
Preferably the cold air cavity flow design is 5 ~ 10kg/s, and inside circumference evenly sets up 8 baffles, will the cold air cavity is cut apart into a plurality of independent cavitys, and every independent cavity corresponds the cold air inlet of the same quantity, cold air steady flow hole, cold air mixing hole, cold air blow-off hole, and the corresponding maximum velocity of flow of cold air passageway size is less than 8m/s.
Compared with the existing mixing device, the mixing device reduces the overall temperature loss of the mixing device through the modes such as the high-temperature hot gas radial opposed mixing section internal pneumatic configuration, the specific cold air injection mode, the short steady flow section and the overall heat insulation and preservation scheme of the double-layer shell, and the whole device has the functions of accurate temperature control, stable pressure, uniform flow, different flow tests of engine test pieces and the like, and simultaneously meets the requirements of low temperature loss and uniform air flow tests of a 30-80 kg/s novel engine test bed by matching with the high-temperature hot gas flow fractional gear adjusting function.
Compared with a similar single-stranded high-temperature airflow and cold air mixing device, the device adopts the unique designs of high-temperature hot air radial opposite-flushing blowing, anti-turning flat shell of the mixing section, anti-turning holes of the cold air and the like, and is beneficial to solving the problems of heat prevention, temperature loss reduction, uniform airflow and the like of the mixing device for the large-flow test bed.
Drawings
FIG. 1 is a schematic view of a blending apparatus according to the present invention.
Description of the symbols:
1 high-temperature hot gas inlet; 2 a cold air inlet; 3, a cold air cavity; 4, a cold air steady flow hole; 5 cold air anti-turning holes; 6 cold air mixing holes; 7 blowing cold air off the holes; 8, turning the mixing section to a flat outer shell; 9 mixing section expanding section outer shell-water cooling shell; 10 mixing section straight section outer shell; 11 mixing section contraction section outer shell-water cooling shell; 12 constant flow section equal straight section outer shell-water cooling shell; 13 a choke ring; 14 a porous inner insulating shell; 15 pressure regulating exhaust holes; 16 a steady flow section contraction section shell; 17 a specific engine test piece throttling throat; 18 pressure regulating pipes; 19 an exhaust cooling section; 20 pressure regulating valve
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The blending device of the invention for a plurality of strands of high-temperature hot air and cold air for an engine test bed is shown in figure 1. A plurality of strands of high-temperature hot gas with a certain flow rate are blown into the inner cavity of the blending section from the high-temperature hot gas inlet 1; cold air with micro-adjustable flow enters the cold air cavity through a plurality of cold air inlets which are uniformly distributed in the circumferential direction, and then is blown into the inner cavity of the mixing section through cold air stabilizing holes, cold air anti-turning holes, cold air mixing holes and cold air blow-off holes which penetrate through the outer shells and the porous inner heat insulation shell of the mixing section; in the inner cavity of the blending section, the high-temperature hot gas and the cold air are blown in to complete blending; after mixing, airflow enters the cavity in the straight section of the steady flow section to finish rectification, and a uniform test medium is obtained; the uniform test medium is supplied to an engine test piece through the steady flow section contraction section and the throttling throat, and the redundant test medium is discharged into the atmosphere through the pressure regulating exhaust hole, the pressure regulating pipeline, the exhaust cooling section, the steady flow section pressure regulating valve and the like in sequence. The scheme of the invention is explained in detail as follows:
(1) the designed flow of high-temperature hot air of the mixing device is 50-80 kg/s, the designed flow of cold air is 5-10 kg/s, the ratio of the cold air to the cold air is lower than 15%, the designed flow of maximum exhaust is 30kg/s, and the requirement of the test flow range of the whole engine is met by 30-80 kg/s.
(2) The flow design of the high-temperature hot gas inlet 1 is 50-80 kg/s, the high-temperature hot gas inlets 1 are uniformly arranged in the circumferential direction, the number of the high-temperature hot gas inlets is preferably 8, the axis of each high-temperature hot gas inlet is perpendicular to the axis of the blending device, the flow rate corresponding to the preferred inner diameter is not lower than 110m/s, the wall surface of each high-temperature hot gas inlet is cooled by water and prevented from heating, and a pressure regulating valve and an air inlet throttling throat are arranged on the upstream of each high. The high-temperature hot gas is blown into the inner cavity of the blending section at a higher speed, so that the high-temperature hot gas has better anti-interference performance; the 8 high-temperature hot gas inlets 1 are arranged in a radial opposite impact mode, parameters are completely the same, the high-temperature hot gas radially collides near the axis of the cavity in the blending section, partial high-temperature hot gas radial kinetic energy is dissipated, the length of a subsequent rectifying device is reduced, meanwhile, multiple strands of high-temperature hot gas are more fully mixed, and the uniformity of the gas flow is improved; the upstream of each high-temperature hot gas inlet 1 is provided with a pressure regulating valve and an inlet throttling throat, is arranged at the upstream of the two-stage heater and is a normal-temperature device, and the flow of the high-temperature hot gas path can be regulated in a fractional step manner; on the premise of fractional adjustment of the high-temperature hot airflow, the design difficulty of the two-stage heater at the upstream of the mixing device can be reduced by considering that the temperature hysteresis effect of gas heating is high, and the temperature adjustment of the high-temperature airflow at the outlet is easier to realize by the two-stage heater.
(3) The inner cavity of the mixing section adopts an expansion and contraction pneumatic structure, the diameter of the equal straight section of the inner cavity of the mixing section is preferably 1.3 times that of the equal straight section of the steady flow section, and the overall length of the inner cavity of the mixing section is preferably 2 times that of the equal straight section; a turning flat plate structure is arranged near the axis of the front end, and the diameter of the flat plate is preferably 0.5-0.6 times of that of the equal straight section of the cavity in the blending section. A steering flat plate structure is arranged near the axis of the front end of the mixing section to force the high-temperature hot gas to flow to the direction of the steady flow section.
(4) The flow of the cold air inlets 2 is designed to be 5-10 kg/s and is circumferentially and uniformly arranged, the axes of the cold air inlets are perpendicular to the axis of the blending device, the number of the preferred air inlets is 8, and the flow speed corresponding to the inner diameter of the preferred cold air inlet is 20-40 m/s. The cold air inlet 2 is provided with a pressure regulating valve and a throttling throat at the upstream after being connected in parallel by adopting a pipeline, the pressure in front of the throttling throat is accurately and micro-regulated, the micro-regulation of the cold air flow is realized, and the cold air flow is directly mixed with high-temperature hot air, so that the stable control of the temperature of the high-temperature air flow in a mixing device is realized; 8 cold air intakes are in radial hedging layout, improve cold air homogeneity.
(5) The flow design of the cold air cavity 3 is 5-10 kg/s, a closed cavity is formed by wrapping the outer shell of the mixing section through the outer shell of the cold air cavity, a plurality of partition plates are uniformly arranged in the inner circumferential direction, the cold air cavity is divided into a plurality of independent cavities, each independent cavity corresponds to the same number of cold air inlets 2, cold air stabilizing holes 4, cold air mixing holes 6 and cold air blow-off holes 7, the number of the partition plates is preferably 8, the size of each cold air channel corresponds to the maximum flow speed which is preferably lower than 8m/s, the flow in the cold air cavity is uniform through the design, the flow of the cold air stabilizing holes, the cold air mixing holes and the cold air blow-off holes in the shell of the downstream mixing section is distributed according to the design, the heat prevention effect and the heat insulation effect of the mixing section under the smaller cold air flow are ensured, and meanwhile the low disturbance of the cold.
(6) The overall heat-proof heat-preservation layout scheme of the porous inner-layer heat-insulation shell and each section of outer-layer shell is adopted. The porous inner layer heat insulation shell is made of high-temperature alloy materials, the thickness is preferably 3-5 mm, micropores are uniformly distributed on the porous inner layer heat insulation shell, the diameter of each micropore is preferably 2-3 mm, and the distance between every two adjacent micropores is preferably 20 mm; a gap layer is arranged between the porous inner-layer heat-insulating shell and each outer-layer shell, and a flow blocking ring 13 is axially arranged on the gap layer to prevent airflow of the gap layer from flowing along the axial direction and reduce the convective heat transfer of the airflow in the gap layer, the thickness of the gap layer is preferably 30mm or more, the inner surface of the flow blocking ring 13 is connected with the porous inner-layer heat-insulating shell in a welding way, the outer surface of the flow blocking ring 13 is in clearance fit with each section of outer-layer shell, and the distance between the flow blocking rings along the; the outer shells of the blending section steering flat plate, the expansion section, the blending section contraction section and the steady flow section are water-cooled shells, the outer shells of the blending section isoplanatic section are cooled through cold air heat exchange of a cold air cavity, and the wall thickness of each outer shell is determined according to the pressure-bearing requirement. Through the static air bed of being close in the interstitial layer, make between porous inlayer thermal-insulated casing and each outer casing can only pass through air heat-conduction and the radiation mode heat transfer between the surface, the heat transfer capacity of these two kinds of heat transfer modes is less than the heat transfer capacity of convection heat transfer under 1000 ℃ of the ranks service behavior, double-deck casing design makes the casing thermal-insulated ability improve, under the effect of high temperature test medium, porous inlayer casing bears the high temperature and does not bear the high pressure, each section outer casing bears the high pressure and does not bear the high temperature, can change the design and satisfy the high temperature high pressure resistant demand. Meanwhile, the porous inner shell is a high-temperature shell, so that the temperature difference between the shell and the internal airflow is greatly reduced, the on-way heat transfer energy loss of the high-temperature airflow is reduced, and the temperature loss of the high-temperature airflow in the mixing device is reduced.
(7) The design flow rate of cold air of the cold air anti-turning holes 5 in the blending section is preferably not less than 2%, the holes are circumferentially and uniformly arranged, the hole axis is parallel to the axis of the blending device, two circles of cold air anti-turning holes are arranged, the number of the inner circle holes is preferably 8, the number of the outer circle holes is preferably 16, the flow rate of cold air in the holes corresponding to the preferred hole diameter is not less than 90m/s, and the cold air anti-turning holes are provided with independent pipe walls and penetrate through the blending section to turn to the inner shell and the outer shell of the flat plate. Firstly, aiming at the radial opposite impact behavior of high-temperature hot gas near the axis of the mixing device, the thermal shock of the high-temperature hot gas on a mixing section steering flat plate due to radial opposite impact backflow can be reduced by the dispersed cold air blowing mode with a certain blowing speed, and the high-temperature airflow resistance of a porous inner layer heat insulation shell corresponding to the mixing section steering flat plate is improved; secondly, a small amount of cold air is blown into the inner cavity of the mixing section through the dispersed cold air stabilizing holes, so that the disturbance intensity of the cold air can be reduced; thirdly, through the blowing-in mode, oppositely-flushed high-temperature air in the inner cavity of the blending section is stably blown away from the inner-layer heat-insulating shell of the expansion section of the blending section, so that the heat exchange effect of high-temperature hot gas and the wall surface is reduced, and the temperature loss of high-temperature air flow in the blending device is reduced; fourthly, the design of penetration of the cold air anti-turning hole enables cold air not to enter a gap layer between the inner shell and the outer shell, the speed of air flow speed in the gap layer is not increased, the convective heat transfer effect of the gap layer between the inner shell and the outer shell in the expansion section of the mixing section is ensured to be at a low level, and the low temperature loss of internal high-temperature air flow is ensured.
(8) The design flow rate of cold air of the cold air steady flow holes 4 in the blending section is preferably 2% -3%, the cold air steady flow holes are uniformly arranged in the circumferential direction, 2 rows of cold air steady flow holes are arranged, the number of holes in a single row of holes is preferably 24, the axis extension lines of all the holes pass through the axis of the blending device, the holes and the axis of the blending device form an included angle, so that the cold air is blown into the inner cavity of the blending section along with the air flow, the preferred included angle is 45 degrees, the flow rate of cold air in the holes corresponding to the preferred hole diameter is not lower than 90m/s, and the cold air steady flow holes are provided. On one hand, a small amount of cold air is blown into the inner cavity of the mixing section through the dispersed cold air stabilizing holes, so that the disturbance intensity of the cold air can be reduced; on the other hand, by adopting the blowing mode, the high-temperature air in the inner cavity expansion section of the blending section is stably blown away from the inner layer heat insulation shell of the expansion section of the blending section, so that the heat exchange effect of high-temperature hot gas and the wall surface is reduced, and the temperature loss of high-temperature air flow in the blending device can be reduced; and thirdly, the cold air flow stabilizing hole penetrates through the gap layer between the inner shell and the outer shell in a design, so that the speed of the air flow speed in the gap layer is not increased, the convective heat transfer effect of the gap layer between the inner shell and the outer shell in the expansion section of the mixing section is ensured to be at a low level, and the low temperature loss of the internal high-temperature air flow is ensured.
(9) The design flow rate of cold air of the cold air mixing holes 6 in the mixing section is preferably 3% -6%, the row number of the axial holes is preferably 4, the single row of holes are circumferentially and uniformly arranged, the number of the single row of holes is preferably 24, the extension lines of the axes of all the holes pass through the axis of the mixing device and are perpendicular to the axis, the flow rate of cold air in the holes corresponding to the preferred hole diameter is not lower than 90m/s, and the cold air mixing holes are provided with independent pipe walls and penetrate through the inner shell and the outer shell of the expanding section of the mixing section. On one hand, cold air is blown into the inner cavity of the blending section through the dispersed cold air blending holes, so that the disturbance intensity of the cold air can be reduced; on the other hand, a small amount of cold air is blown into the inner cavity of the equal straight section of the blending section through the cold air blending hole, so that high-temperature air flow can be far away from the wall surface of the equal straight section, the heat exchange effect of high-temperature hot air and the wall surface is reduced, and the temperature loss of the high-temperature air flow in the blending device can be reduced; and thirdly, the cold air mixing holes are designed in a penetrating way, so that cold air does not enter a gap layer between the inner shell and the outer shell, the speed of the air flow speed in the gap layer is not increased, the convective heat exchange effect of the gap layer between the inner shell and the outer shell in the equal straight section of the mixing section is ensured to be at a low level, and the low temperature loss of the high-temperature air flow inside the mixing section is ensured.
(10) The design flow of cold air blow-off holes 7 accounts for preferred 3% in the blending section, set up 2 rows of cold air blow-off holes, for circumference evenly arranged, the hole number of single row cold air blow-off holes is preferred 24, the axis extension line of all holes passes through the blending device axis, the hole makes the counter current air current of cold air blow-off in the interior cavity of blending section with the blending device axis contained angle, preferred contained angle is 60, the downthehole cold air flow rate that preferred aperture corresponds is not less than 90m/s, the cold air blow-off hole has independent pipe wall, run through the interior shells and the exterior shells of blending section shrink section. On one hand, the dispersed cold air blow-off holes blow cold air into the inner cavity of the blending section, so that the disturbance intensity of the cold air can be reduced; on the other hand, a small amount of cold air is blown into the inner cavity of the contraction section of the blending section through the cold air blow-off holes, so that high-temperature air flow can be far away from the wall surface of the contraction section of the blending section, the heat exchange effect of high-temperature hot air and the wall surface is reduced, and the temperature loss of the high-temperature air flow in the blending device can be reduced; and thirdly, the cold air blow-off holes are designed in a penetrating way, so that the cold air does not enter the gap layer between the inner shell and the outer shell, the speed of the air flow velocity in the gap layer is not increased, the convective heat exchange effect of the gap layer between the inner shell and the outer shell in the equal straight section of the mixing section is ensured to be at a low level, and the low temperature loss of the high-temperature air flow in the mixing section is ensured.
(11) And a short steady flow section pneumatic layout is adopted, the flow velocity of the steady flow section corresponding to the inner diameter of the steady flow section is preferably not higher than 40m/s, and the length of the constant straight section of the steady flow section is preferably 3 times of the inner diameter of the constant straight section. On one hand, the specific cold air injection mode is adopted, so that the disturbance intensity of the cold air is low, and the requirement on uniformity of airflow can be met by adopting the short steady flow section pneumatic layout; on the other hand, the short steady flow section layout is adopted, the energy loss distance of the high-temperature airflow is reduced, and the temperature loss of the high-temperature airflow is reduced.
(12) The maximum flow design requirement of the pressure-regulating exhaust holes 15 is 30kg/s, the pressure-regulating exhaust holes are arranged near the outlet of the steady flow section and are circumferentially and uniformly arranged, the number of the optimized holes is 8, the extension lines of the hole axes are intersected and vertical to the axis of the rectifying device, the optimized hole diameter corresponds to the air airflow speed of 60-100 m/s, and the shell of the pressure-regulating exhaust holes is a water-cooling pressure-bearing shell.
(13) The downstream of the pressure regulating exhaust hole is sequentially provided with a pressure regulating pipeline 18, an exhaust cooling section 19 and a pressure regulating valve 20, the shell of the pressure regulating pipeline 18 is a water-cooled shell, the exhaust cooling section 19 preferably adopts a water spray cooler or a shell-and-tube heat exchanger, and the pressure regulating valve 20 adopts a conventional pressure regulating valve. And redundant high-temperature air flow in the mixing device is discharged by adjusting the pressure regulating valve, so that the pressure stability control of the high-temperature air flow is realized.
(14) And the downstream of the outlet of the steady flow section is provided with throttling throats of specific engine test pieces with different sizes, and the throttling throats are combined with the system, so that the whole engine test requirement of 30-80 kg/s of flow is met, and the low-temperature loss and airflow uniformity requirements of a novel test bed are met.
Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.

Claims (10)

1. The utility model provides an engine test bench is with mixing device of stranded high temperature steam and cold air which characterized in that: the mixing section inner cavity is formed by sequentially connecting an expansion section, an equal straight section and a contraction section, the front end of the mixing section inner cavity is provided with a steering flat plate for plugging an inlet of the expansion section, and the rear end of the mixing section inner cavity is connected with the steady flow section; the cold air cavity is formed by sealing and wrapping the cavity in the mixing section through an outer shell, a plurality of high-temperature hot air inlets are uniformly and circumferentially arranged on the side wall, close to the front end, of the cavity in the mixing section, each high-temperature hot air inlet penetrates through the outer shell to be connected with a high-temperature air source, the central axis of each high-temperature hot air inlet is perpendicular to the axis, a plurality of cold air inlets are uniformly and circumferentially arranged on the side wall, close to the front end, of the outer shell, and the central axis of each cold air inlet is perpendicular to the axis; a plurality of cold air anti-steering holes are uniformly arranged on the steering flat plate circumferentially around the axis, and the axis of each cold air anti-steering hole is parallel to the axis; the expansion section is provided with a plurality of cold air stabilizing holes, the equal straight section is provided with a plurality of cold air mixing holes, and the contraction section is provided with a plurality of cold air blowing-off holes for blowing in cold air against airflow; the stationary flow section comprises a short equal straight section and a contraction section, a plurality of pressure regulating exhaust holes are formed in the side wall of the rear portion of the short equal straight section, and a pressure regulating valve and an exhaust cooling section are arranged on a pressure regulating pipeline connected with the pressure regulating exhaust holes.
2. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the high-temperature hot gas inlets are arranged in a radial hedging mode, and 8 high-temperature hot gas inlets are arranged in a radial hedging mode.
3. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the cold air inlets are arranged in 8 in a radially opposed manner.
4. The blending device of the plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 2, characterized in that: the diameter of the steering flat plate is 0.5-0.6 times of the diameter of the straight section of the cavity in the blending section, the cold air anti-steering holes are formed in the steering flat plate to form an inner circle and an outer circle, the inner circle is uniformly and circumferentially provided with 8 cold air anti-steering holes, the outer circle is uniformly and circumferentially provided with 16 cold air anti-steering holes, and the cold air anti-steering holes are provided with independent pipe walls and penetrate through the inner shell and the outer shell of the steering flat plate.
5. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: cold air steady flow hole is provided with two rows, and every row has evenly arranged 24 along circumference, and all porose axis extension lines all pass through the axis, and all with the contained angle of axis is 45, makes the cold air following current blow in the cavity in the blending section, the anti steady flow hole of cold air has independent pipe wall, runs through change the ectonexine casing of blending section expansion section.
6. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the cold air mixing holes are axially provided with 4 rows, each row is uniformly provided with 24 holes along the circumferential direction, and the cold air anti-mixing holes are provided with independent pipe walls and penetrate through the inner and outer shells of the equal straight sections of the rotary mixing section.
7. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the cold air blows off the hole and is provided with two rows, and every row has evenly arranged 24 holes along circumference, and all porose axis extension lines all pass through the axis, and all with the axis becomes 60 contained angles, makes the anti-airflow of cold air blow in the cavity in the blending section, the anti-blow off hole of cold air has independent pipe wall, runs through change the ectonexine casing of blending section shrink section.
8. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the diameter of the equal straight section of the cavity in the blending section is 1.3 times of that of the equal straight section of the steady flow section, the overall length of the cavity in the blending section is 2 times of that of the equal straight section, and the length of the equal straight section of the steady flow section is 3 times of that of the equal straight section.
9. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to claim 1, characterized in that: the number of the pressure-regulating exhaust holes is 8 along the circumferential direction, the extension line of the hole axis is intersected with and perpendicular to the axis, the air flow speed in the hole corresponding to the aperture is 60-100 m/s, and the maximum flow design requirement is 30 kg/s.
10. The blending device of a plurality of strands of high-temperature hot gas and cold air for the engine test bed according to any one of claims 1 to 9, characterized in that: the design of cold air cavity body flow is 5 ~ 10kg/s, and inside circumference evenly sets up 8 baffles, will the cold air cavity is cut apart into a plurality of independent cavitys, and every independent cavity is corresponding the cold air inlet of the same quantity, cold air steady flow hole, cold air mixing hole, cold air blow-off hole, and the corresponding maximum velocity of flow of cold air passageway size is less than 8m/s.
CN201911370955.5A 2019-12-26 2019-12-26 Blending device of multi-strand high-temperature hot gas and cold air for engine test bed Pending CN110940525A (en)

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3899923A (en) * 1971-05-13 1975-08-19 Teller Environmental Systems Test process and apparatus for treatment of jet engine exhaust
CN2077952U (en) * 1989-12-23 1991-05-29 北京航空航天大学 Burner for kiln
RU2308566C1 (en) * 2006-01-10 2007-10-20 Федеральное государственное образовательное учреждение высшего профессионального образования "Новочеркасская государственная мелиоративная академия" ФГОУ ВПО (НГМА) Hydrodynamic cavitational apparatus (variants) and mesh fish-pass web flushing device
CN101486022A (en) * 2009-02-19 2009-07-22 山东科技大学 Prewarming internal mixed nozzle
CN203490076U (en) * 2013-09-12 2014-03-19 沈阳黎明航空发动机(集团)有限责任公司 Aeroengine ground indoor stand air intake heating device
CN203837917U (en) * 2014-04-08 2014-09-17 中国燃气涡轮研究院 Cone wall hole type non-isothermal air inlet mixing device
CN104075319A (en) * 2014-06-19 2014-10-01 广东正鹏生物质能源科技有限公司 Biomass gas combustion device used for industrial boiler
CN204901833U (en) * 2015-06-10 2015-12-23 北京华清燃气轮机与煤气化联合循环工程技术有限公司 Sprayer and be equipped with gas turbine of this sprayer
CN109718679A (en) * 2018-12-25 2019-05-07 中国航天空气动力技术研究院 A kind of mixed stable voltage chamber device

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3899923A (en) * 1971-05-13 1975-08-19 Teller Environmental Systems Test process and apparatus for treatment of jet engine exhaust
CN2077952U (en) * 1989-12-23 1991-05-29 北京航空航天大学 Burner for kiln
RU2308566C1 (en) * 2006-01-10 2007-10-20 Федеральное государственное образовательное учреждение высшего профессионального образования "Новочеркасская государственная мелиоративная академия" ФГОУ ВПО (НГМА) Hydrodynamic cavitational apparatus (variants) and mesh fish-pass web flushing device
CN101486022A (en) * 2009-02-19 2009-07-22 山东科技大学 Prewarming internal mixed nozzle
CN203490076U (en) * 2013-09-12 2014-03-19 沈阳黎明航空发动机(集团)有限责任公司 Aeroengine ground indoor stand air intake heating device
CN203837917U (en) * 2014-04-08 2014-09-17 中国燃气涡轮研究院 Cone wall hole type non-isothermal air inlet mixing device
CN104075319A (en) * 2014-06-19 2014-10-01 广东正鹏生物质能源科技有限公司 Biomass gas combustion device used for industrial boiler
CN204901833U (en) * 2015-06-10 2015-12-23 北京华清燃气轮机与煤气化联合循环工程技术有限公司 Sprayer and be equipped with gas turbine of this sprayer
CN109718679A (en) * 2018-12-25 2019-05-07 中国航天空气动力技术研究院 A kind of mixed stable voltage chamber device

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
张珺 等: ""导流锥角度对室内发动机试车台影响的研究"", 《机械管理开发》 *
曹海峰 等: ""基于CFD的航空发动机试车台进气加温装置气动性能分析"", 《燃气涡轮试验与研究》 *

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