CN106198030A - Tail room for engine testsand gas extraction system - Google Patents

Abstract

The invention discloses a kind of tail room for engine testsand gas extraction system, straight section and the tail room expansion segments such as tail room includes big tail room and replaceable little tail room, and big tail room includes the tail room converging portion connected, tail room, replaceable little tail room is arranged in the converging portion of tail room, and is connected with tail room converging portion；Straight section, tail room expansion segment and the replaceable little tail rooms such as tail room converging portion, tail room are hollow revolving body；Electromotor and the tail room converging portion with nozzle are arranged in altitude simulation cabin, and tail room expansion segment is arranged on altitude simulation out of my cabin, and electromotor is supersonic speed electromotor.The tail room of the present invention, improves follow-up air-extractor and passively flows to a mouthful static pressure, reduces follow-up air-extractor pressure ratio, and then decrease injector progression or the volume of vacuum tank of follow-up air-extractor, meanwhile, the little tail cell structure of replacing is set, meets the demand of sizes engine test.

Description

Tail room for engine testsand gas extraction system

Technical field

The present invention relates to a kind of tail room for engine testsand gas extraction system, especially a kind of supersonic speed that is used for is started The tail room of machine test bay gas extraction system.

Background technology

When in ground simulation supersonic speed electromotor high-altitude flight state, the most first electromotor is arranged on altitude simulation cabin In, use air-extractor stratochamber to be bled so that residing height when the pressure in altitude simulation cabin and electromotor high-altitude flight The ambient pressure of degree is identical, then carries out engine ignition, carries out high-altitude flight simulation test, to remain in process of the test Pressure in altitude simulation cabin is identical with the ambient pressure of residing height during electromotor high-altitude flight, and this is accomplished by instant by Supersonic Speed electromotor expellant gas discharges altitude simulation cabin, in prior art, generally uses injector or vacuum tank to bleed, and Altitude simulation pressure out of my cabin is usually 0.11MPa, and the ambient pressure of supersonic speed engine flight height is then only atmospheric pressure 0.1 times of power, even 0.01 times, the pressure ratio of gas extraction system to reach 10 to 100, and the flow of corresponding gas extraction system import is every Second then up to tens kilograms the most up to a hundred kilograms, the biggest pressure ratio and by draught jet capacity, only by the supercharging of injector, it is necessary to Three connect to level Four, if using vacuum tank, then the volume of vacuum tank up to go up ten thousand stere, it can be seen that, the most individually Using injector or vacuum tank as air-extractor, be required to huge structure, not only inefficiency, expense is the most sufficiently expensive； Secondly, engine testsand generally need to carry out high-altitude flight simulation to various engines, and different electromotors, the chi of electromotor Very little, nozzle size, engine export flow are the most different, use a set of air-extractor, it is impossible to meet various engines Test requirements document.

Summary of the invention

The defect that the invention aims to overcome above-mentioned prior art to exist and provide and a kind of engines tail sprayed The kinetic energy of pipe stagnation effectively, improves follow-up air-extractor and passively flows to a mouthful static pressure, reduce the supercharging needed for follow-up air-extractor Ratio, the tail room of the most applicable sizes engine test.

The purpose of the present invention can be achieved through the following technical solutions:

A kind of tail room for engine testsand gas extraction system, described tail room includes fixing big tail room and replaceable little tail Room, according to nozzle exiting exhaust gas flow direction, described fixing big tail room includes the tail room being coaxially fixedly connected sequentially Converging portion, straight section and the tail room expansion segment such as tail room, described replaceable little tail room is arranged in the converging portion of described tail room, and with described Tail room converging portion is fixedly and coaxially connected；Straight section, tail room expansion segment and the replaceable little tail rooms such as described tail room converging portion, tail room are Hollow revolving body；Electromotor and the described tail room converging portion with nozzle are arranged in altitude simulation cabin, described tail Room expansion segment is arranged on altitude simulation out of my cabin, and described electromotor is supersonic speed electromotor.

Further, fixing big tail room is provided with the water-spraying control dress for cooling down nozzle exiting exhaust gas Put.

Further, described replaceable little tail room includes little tail room flange and little tail room cylinder, the institute being fixedly and coaxially connected State little tail room cylinder to be arranged in the converging portion of described tail room, described little tail room flange and be fixedly installed on described tail room converging portion and enter The fixing big tail room flange of mouth is bolted to connection.

Further, a diameter of D of described tail room converging portion entrance_w, convergency is α_wr；The diameter of the straight sections such as described tail room D_wkp, a length of L_wkp；A diameter of D of described tail room expansion segment outlet_wc, the angle of flare is α_wc；Described D_w, D_wkp, L_wkpMeet following Equation group:

$M_w={\[\frac{2}{k-1}(\mathrm{\π}{\left(M_w\right)}^{\frac{-(k-1)}{k}}-1)\]}^{0.5}---\left(1\right);$

$\mathrm{\π}\left(M_w\right)=\frac{P_w}{P_{t5}}---\left(2\right);$

$D_w={\[{(1+\frac{k-1}{2}{M}_W^2)}^{\frac{k-1}{2(k-1)}}/0.5M_w{(k+1)}^{\frac{(k+1)}{2(k-1)}}\]}^{0.5}{d}_{4kp}---\left(3\right);$

${\stackrel{\‾}{P}}_{tws}={\[\frac{(k+1)M_W^2}{(k-1)M_w^2+2}\]}^{\frac{k}{k-1}}{\[\frac{k+1}{2{\mathrm{kM}}_w^2-k+1}\]}^{\frac{1}{k-1}}---\left(4\right);$

$q\left(M_w\right)=\frac{M_W{\left(0.5\right(k+1\left)\right)}^{(k+1)/2(k-1)}}{{(1+0.5(k-1\left){M_W}^2\right)}^{(k+1)/2(k-1)}}---\left(5\right);$

$D_{wkp}=d_{4kp}{\left(\frac{q\left(M_w\right)}{{\stackrel{\‾}{p}}_{tws}}\right)}^{0.5}---\left(6\right);$

L_wkp=4D_wkp(7)；

In above-mentioned equation group: M_w: tail room converging portion entrance Mach number；K: specific heat ratio；π(M_w): tail room converging portion entrance Mach The static pressure of number correspondence and stagnation pressure ratio；P_w: the static pressure that tail room converging portion entrance Mach number is corresponding, unit is pa；P_t5: tail room is restrained The stagnation pressure that section entrance Mach number is corresponding, unit is pa；D_w: the diameter of tail room converging portion entrance, unit is mm；d_4kp: electromotor larynx Road diameter, unit is mm；After the normal shock wave that tail room converging portion entrance Mach number is corresponding with normal shock wave before overall pressure tatio；q (M_w): the velocity coeffficient that tail room converging portion entrance Mach number is corresponding；D_wkp: the diameter of the straight sections such as tail room, unit is mm；L_wkp: tail The length of the straight sections such as room, unit is mm；

Wherein, real environment when the static pressure that converging portion entrance Mach number in tail room is corresponding and supersonic speed electromotor high-altitude flight Pressure is identical, the outlet Mach of stagnation pressure corresponding to tail room converging portion entrance Mach number and the nozzle of supersonic speed electromotor The stagnation pressure that number is corresponding is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, starting of supersonic speed electromotor Tail nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed is started Real ambient pressure during machine high-altitude flight, specific heat ratio and supersonic speed electromotor throat diameter are that supersonic speed electromotor is intrinsic Known parameters, the parameter in above-mentioned equation group: M_w, k, π (M_w), P_w, P_t5, W_w, d_4kp,q(M_w), D_wkp, L_wkpIt is Supersonic In the supersonic speed electromotor of all tests of speed nozzle aerofluxus simulation test, nozzle rate of discharge is maximum Parameter corresponding to supersonic speed electromotor.

Further, described convergency meets: 0 ＜ α_wr≤12°；The described angle of flare meets 0 ＜ α_wc≤12°。

Further, a diameter of D of described replaceable little tail room_wx, described D_wxMeet following equations group:

$M_{wx}={\[\frac{2}{k-1}(\mathrm{\π}{\left(M_{wx}\right)}^{\frac{-(k-1)}{k}}-1)\]}^{0.5}---\left(8\right);$

$\mathrm{\π}\left(M_{wx}\right)=\frac{P_{wx}}{P_{t5x}}---\left(9\right);$

$D_{wx}={\[{(1+\frac{k-1}{2}{M}_{Wx}^2)}^{\frac{k-1}{2(k-1)}}/0.5M_{wx}{(k+1)}^{\frac{(k+1)}{2(k-1)}}\]}^{0.5}{d}_{4kpx}---\left(10\right);$

In above-mentioned equation group: M_wx: replaceable little tail chamber inlet Mach number；π(M_wx): replaceable little tail chamber inlet Mach number Corresponding static pressure and stagnation pressure ratio；P_wx: the static pressure that replaceable little tail chamber inlet Mach number is corresponding, unit is pa；P_t5x: replaceable The stagnation pressure that little tail chamber inlet Mach number is corresponding, unit is pa；D_wx: replaceable little tail chamber inlet diameter, unit is mm；d_4kpx: remove The supersonic speed electromotor throat diameter of the test beyond the test engine of engine export maximum flow, unit is mm；

Wherein, real ring when the static pressure that replaceable little tail chamber inlet Mach number is corresponding and supersonic speed electromotor high-altitude flight Border pressure is identical, the outlet of stagnation pressure corresponding to replaceable little tail chamber inlet Mach number and the nozzle of supersonic speed electromotor The stagnation pressure that Mach number is corresponding is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, supersonic speed electromotor Nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed During electromotor high-altitude flight in real ambient pressure, specific heat ratio and engine testsand in the electromotor of all tests, remove The electromotor throat diameter of the electromotor beyond electromotor that nozzle rate of discharge is maximum is that supersonic speed electromotor is solid Some known parameters, the parameter in above-mentioned equation group: M_wx, π (M_wx), P_wx, P_t5x, D_wx, d_4kpx, it is in engine testsand institute Have in the electromotor of test, the ginseng that supersonic speed electromotor in addition to the electromotor that nozzle rate of discharge is maximum is corresponding Number.

Further, a length of L of described little tail room cylinder_wx, the length of described little tail room cylinder meets 500mm≤L_wx ≤600mm。

Further, the outlet of nozzle is L with the distance of the entrance section of tail room converging portion_ww, described The outlet of nozzle meets 100mm≤L with the distance of the entrance section of tail room converging portion_ww≤150mm。

Further, the outlet of nozzle is 120mm with the distance of the entrance section of tail room converging portion.

Further, the outlet of described tail room expansion segment connects injector or vacuum tank.

Arrange of the present invention behind the tail room of engine testsand gas extraction system, when engine export maximum flow Test engine when testing, the supersonic gas that nozzle outlet is discharged flows into tail room converging portion, passes through The tail cell structure of Laval nozzle shape dress, by a series of Shock Wave, finally reduces to subsonic speed, and tail room converging portion enters a kind of horse raised north of the Grean Wall Stagnation pressure P after the normal shock wave that conspicuous number is corresponding_tw, the static pressure P in the altitude simulation cabin that tail room converging portion entrance Mach number is corresponding_WAnd tail The pressure ratio of roomMeet formula (11)-(13)；

$P_{tw}={\stackrel{\‾}{P}}_{tws}{P}_{t5}---\left(11\right)$

$P_W=P_{t5}{(1+\frac{k-1}{2}{\mathrm{Mw}}^2)}^{\frac{-K}{(k-1)}}---\left(12\right)$

${\stackrel{\‾}{P}}_{tww}=\frac{P_{tw}}{P_W}---\left(13\right);$

When test engine in addition to the test engine except engine export maximum flow is tested, engines tail The supersonic gas that nozzle exit is discharged flows in the replaceable little tail room of correspondence, by the tail room of class Laval nozzle shape Structure, by a series of Shock Wave, after finally reducing to the normal shock wave that the replaceable little tail chamber inlet Mach number of subsonic speed is corresponding Stagnation pressure P_twx, the static pressure P in the altitude simulation cabin that replaceable little tail chamber inlet Mach number is corresponding_WxAnd the pressure ratio of tail room Meet formula (14)-(17)；

${\stackrel{\‾}{P}}_{twsx}={\[\frac{(k+1)M_{wx}^2}{(k-1)M_{wx}^2+2}\]}^{\frac{k}{k-1}}{\[\frac{k+1}{2{\mathrm{kM}}_{wx}^2-k+1}\]}^{\frac{1}{k-1}}---\left(14\right);$

$P_{twx}={\stackrel{\‾}{P}}_{twsx}{P}_{t5x}---\left(15\right)$

$P_{Wx}=P_{t5x}{(1+\frac{k-1}{2}{M_{wx}}^2)}^{\frac{-K}{(k-1)}}---\left(16\right)$

${\stackrel{\‾}{P}}_{twwx}=\frac{P_{twx}}{P_{Wx}}---\left(17\right);$

Wherein,For after the normal shock wave that replaceable little tail chamber inlet Mach number is corresponding with normal shock wave before overall pressure tatio.

Compared with prior art, the tail room of engine testsand gas extraction system of the present invention, sprayed by class Lavalle The tail room analogue technique of tube shape, under series Shock Wave, gets off the kinetic energy of nozzle stagnation effectively, is more than The pressure ratio of 1 improves follow-up air-extractor and passively flows to a mouthful static pressure, reduces pressure ratio needed for follow-up air-extractor, and then decreases The injector progression of follow-up air-extractor or the volume of vacuum tank, reduce cost, meanwhile, arranges replaceable little tail cell structure, The electromotor correspondence one of a kind of nozzle size changes little tail room, meets the need of sizes engine test Ask.

Accompanying drawing explanation

The invention will be further described with detailed description of the invention below in conjunction with the accompanying drawings.

Fig. 1 is the schematic diagram of the tail room of inventive engine test bay gas extraction system.

Detailed description of the invention

See Fig. 1, a kind of tail room for engine testsand gas extraction system, it is characterised in that described tail room includes solid Fixed big tail room and replaceable little tail room 10, according to nozzle 3 exiting exhaust gas flow direction, described fixing big tail room includes The tail room converging portion 4 being coaxially fixedly connected sequentially, straight section 5 and the tail room expansion segment 6 such as tail room, described replaceable little tail room 1 is arranged In described tail room converging portion 4, and it is fixedly and coaxially connected with described tail room converging portion 4；Described tail room converging portion 4, tail room etc. are straight Section 5, tail room expansion segment 6 and replaceable little tail room 10 are hollow revolving body；There is electromotor 2 and the institute of nozzle 3 Stating tail room converging portion 4 to be arranged in altitude simulation cabin 1, described tail room expansion segment 6 is arranged on outside altitude simulation cabin 1, described in start Machine 2 is supersonic speed electromotor.

Preferably, fixing big tail room is provided with the equipment water jetting cooler for cooling down nozzle 3 exiting exhaust gas.

Preferably, described replaceable little tail room 10 includes little tail room flange 8 and the little tail room cylinder 9 being fixedly and coaxially connected, Described little tail room cylinder 9 is arranged in described tail room converging portion 4, and described little tail room flange 8 is received with being fixedly installed on described tail room The fixing big tail room flange 7 of the section of holding back 4 entrance is bolted to connection.

Preferably, a diameter of D of described tail room converging portion 4 entrance_w, convergency is α_wr；The diameter of the straight sections 5 such as described tail room D_wkp, a length of L_wkp；A diameter of D of described tail room expansion segment 6 outlet_wc, the angle of flare is α_wc；Described D_w, D_wkp, L_wkpMeet following Equation group:

$M_w={\[\frac{2}{k-1}(\mathrm{\π}{\left(M_w\right)}^{\frac{-(k-1)}{k}}-1)\]}^{0.5}---\left(1\right);$

$\mathrm{\π}\left(M_w\right)=\frac{P_w}{P_{t5}}---\left(2\right);$

$D_w={\[{(1+\frac{k-1}{2}{M}_W^2)}^{\frac{k-1}{2(k-1)}}/0.5M_w(k+1)\frac{(k+1)}{2(k-1)}\]}^{0.5}{d}_{4kp}---\left(3\right);$

${\stackrel{\‾}{P}}_{tws}={\[\frac{(k+1)M_W^2}{(k-1)M_w^2+2}\]}^{\frac{k}{k-1}}{\[\frac{k+1}{2{\mathrm{kM}}_w^2-k+1}\]}^{\frac{1}{k-1}}---\left(4\right);$

$q\left(M_w\right)=\frac{M_W{\left(0.5\right(k+1\left)\right)}^{(k+1)/2(k-1)}}{{(1+0.5(k-1\left){M_W}^2\right)}^{(k+1)/2(k-1)}}---\left(5\right);$

$D_{wkp}=d_{4kp}{\left(\frac{q\left(M_w\right)}{{\stackrel{\‾}{p}}_{tws}}\right)}^{0.5}---\left(6\right);$

L_wkp=4D_wkp(7)；

In above-mentioned equation group: M_w: tail room converging portion entrance Mach number；K: specific heat ratio；π(M_w): tail room converging portion entrance Mach The static pressure of number correspondence and stagnation pressure ratio；P_w: the static pressure that tail room converging portion entrance Mach number is corresponding, unit is pa；P_t5: tail room is restrained The stagnation pressure that section entrance Mach number is corresponding, unit is pa；D_w: the diameter of tail room converging portion entrance, unit is mm；d_4kp: electromotor larynx Road diameter, unit is mm；After the normal shock wave that tail room converging portion entrance Mach number is corresponding with normal shock wave before overall pressure tatio；q (M_w): the velocity coeffficient that tail room converging portion entrance Mach number is corresponding；D_wkp: the diameter of the straight sections such as tail room, unit is mm；L_wkp: tail The length of the straight sections such as room, unit is mm；

Wherein, real environment when the static pressure that converging portion entrance Mach number in tail room is corresponding and supersonic speed electromotor high-altitude flight Pressure is identical, the outlet Mach of stagnation pressure corresponding to tail room converging portion entrance Mach number and the nozzle of supersonic speed electromotor The stagnation pressure that number is corresponding is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, starting of supersonic speed electromotor Tail nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed is started Real ambient pressure during machine high-altitude flight, specific heat ratio and electromotor throat diameter are the known ginseng that supersonic speed electromotor is intrinsic Number, the parameter in above-mentioned equation group: M_w, k, π (M_w), P_w, P_t5, W_w, d_4kp,q(M_w), D_wkp, L_wkpIt is engine testsand In all tests electromotor in, the parameter that the maximum electromotor of nozzle rate of discharge is corresponding.

Preferably, described convergency meets: 0 ＜ α_wr≤12°；The described angle of flare meets 0 ＜ α_wc≤12°。

Preferably, a diameter of D of described replaceable little tail room 10_wx, described D_wxMeet following equations group:

$M_{wx}={\[\frac{2}{k-1}(\mathrm{\π}{\left(M_{wx}\right)}^{\frac{-(k-1)}{k}}-1)\]}^{0.5}---\left(8\right);$

$\mathrm{\π}\left(M_{wx}\right)=\frac{P_{wx}}{P_{t5x}}---\left(9\right);$

$D_{wx}={\[{(1+\frac{k-1}{2}{M}_{Wx}^2)}^{\frac{k-1}{2(k-1)}}/0.5M_{wx}{(k+1)}^{\frac{(k+1)}{2(k-1)}}\]}^{0.5}{d}_{4kpx}---\left(10\right);$

In above-mentioned equation group: M_wx: replaceable little tail chamber inlet Mach number；π(M_wx): replaceable little tail chamber inlet Mach number Corresponding static pressure and stagnation pressure ratio；P_wx: the static pressure that replaceable little tail chamber inlet Mach number is corresponding, unit is pa；P_t5x: replaceable The stagnation pressure that little tail chamber inlet Mach number is corresponding, unit is pa；D_wx: replaceable little tail chamber inlet diameter, unit is mm；d_4kpx: remove The supersonic speed electromotor throat diameter of the test beyond the test engine of engine export maximum flow, unit is mm；

Wherein, real ring when the static pressure that replaceable little tail chamber inlet Mach number is corresponding and supersonic speed electromotor high-altitude flight Border pressure is identical, the outlet of stagnation pressure corresponding to replaceable little tail chamber inlet Mach number and the nozzle of supersonic speed electromotor The stagnation pressure that Mach number is corresponding is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, supersonic speed electromotor Nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed During electromotor high-altitude flight in real ambient pressure, specific heat ratio and engine testsand in the electromotor of all tests, remove The electromotor throat diameter of the electromotor beyond electromotor that nozzle rate of discharge is maximum is that supersonic speed electromotor is solid Some known parameters, the parameter in above-mentioned equation group: M_wx, π (M_wx), P_wx, P_t5x, D_wx, d_4kpx, it is in engine testsand institute Have in the electromotor of test, the ginseng that supersonic speed electromotor in addition to the electromotor that nozzle rate of discharge is maximum is corresponding Number.

Preferably, a length of L of described little tail room cylinder 9_wx, the length of described little tail room cylinder 9 meets 500mm≤L_wx ≤ 600mm, it is preferred that a length of 560mm of described little tail room cylinder 9.

Preferably, the outlet of nozzle 3 is L with the distance of the entrance section of tail room converging portion 4_ww, described The outlet of nozzle 3 meets 100mm≤L with the distance of the entrance section of tail room converging portion 4_ww≤150mm。

Preferably, the outlet of nozzle 3 is 120mm with the distance of the entrance section of tail room converging portion 4.

Preferably, the outlet of described tail room expansion segment connects injector or vacuum tank.

Arrange of the present invention behind the tail room of engine testsand gas extraction system, when engine export maximum flow Test engine when testing, the supersonic gas that nozzle outlet is discharged flows into tail room converging portion, passes through The tail cell structure of Laval nozzle shape dress, by a series of Shock Wave, finally reduces to subsonic speed, and tail room converging portion enters a kind of horse raised north of the Grean Wall Stagnation pressure P after the normal shock wave that conspicuous number is corresponding_tw, the static pressure P in the altitude simulation cabin that tail room converging portion entrance Mach number is corresponding_WAnd tail The pressure ratio of roomMeet formula (11)-(13)；

$P_{tw}={\stackrel{\‾}{P}}_{tws}{P}_{t5}---\left(11\right)$

$P_W=P_{t5}{(1+\frac{k-1}{2}{\mathrm{Mw}}^2)}^{\frac{-K}{(k-1)}}---\left(12\right)$

${\stackrel{\‾}{P}}_{tww}=\frac{P_{tw}}{P_W}---\left(13\right);$

When test engine in addition to the test engine except engine export maximum flow is tested, engines tail The supersonic gas that nozzle exit is discharged flows in the replaceable little tail room of correspondence, by the tail room of class Laval nozzle shape Structure, by a series of Shock Wave, finally reduces to subsonic speed, after the normal shock wave that replaceable little tail chamber inlet Mach number is corresponding Stagnation pressure P_twx, the static pressure P of the stratochamber that replaceable little tail chamber inlet Mach number is corresponding_WxAnd the pressure ratio of tail roomMeet Formula (14)-(17)；

${\stackrel{\‾}{P}}_{twsx}={\[\frac{(k+1)M_{wx}^2}{(k-1)M_{wx}^2+2}\]}^{\frac{k}{k-1}}{\[\frac{k+1}{2{\mathrm{kM}}_{wx}^2-k+1}\]}^{\frac{1}{k-1}}---\left(14\right);$

$P_{twx}={\stackrel{\‾}{P}}_{twsx}{P}_{t5x}---\left(15\right)$

$P_{Wx}=P_{t5x}{(1+\frac{k-1}{2}{M_{wx}}^2)}^{\frac{-K}{(k-1)}}---\left(16\right)$

${\stackrel{\‾}{P}}_{twwx}=\frac{P_{twx}}{P_{Wx}}---\left(17\right);$

Wherein,For after the normal shock wave that replaceable little tail chamber inlet Mach number is corresponding with normal shock wave before overall pressure tatio.

Pressure ratio more than 1 improves follow-up air-extractor and passively flows to a mouthful static pressure, reduces supercharging needed for follow-up air-extractor Ratio, and then decrease injector progression or the volume of vacuum tank of follow-up air-extractor, reduce cost；Meanwhile, replacing is set Little tail cell structure, the electromotor correspondence one of a kind of nozzle size is changed little tail room, is met sizes and start The demand of machine test.

Finally illustrating, above example is merely to illustrate technical scheme and unrestricted, although with reference to relatively The present invention has been described in detail by good embodiment, and it will be understood by those of skill in the art that can be to the technology of the present invention Scheme is modified and is equal to replacement, and without deviating from objective and the scope of technical solution of the present invention, it all should be contained in the present invention Right in the middle of.

Claims (10)

1. the tail room for engine testsand gas extraction system, it is characterised in that described tail room include fixing big tail room and Replaceable little tail room (10), according to nozzle (3) exiting exhaust gas flow direction, described fixing big tail room includes coaxially depending on Tail room converging portion (4) of secondary fixing connection, straight section (5) and tail room expansion segment (6) such as tail room, described replaceable little tail room (1) sets Put in described tail room converging portion (4), and be fixedly and coaxially connected with described tail room converging portion (4)；Described tail room converging portion (4), Straight section (5), tail room expansion segment (6) and the replaceable little tail rooms (10) such as tail room are hollow revolving body；There is nozzle (3) electromotor (2) and described tail room converging portion (4) are arranged in altitude simulation cabin (1), and described tail room expansion segment (6) is arranged In altitude simulation cabin (1) outward, described electromotor (2) is supersonic speed electromotor.

Tail room for engine testsand gas extraction system the most according to claim 1, it is characterised in that fixing big tail room On be provided with the equipment water jetting cooler for cooling down nozzle (3) exiting exhaust gas.

Tail room for engine testsand gas extraction system the most according to claim 1, it is characterised in that described replaceable Little tail room (10) includes little tail room flange (8) that is fixedly and coaxially connected and little tail room cylinder (9), and described little tail room cylinder (9) sets Put in described tail room converging portion (4), described little tail room flange (8) and be fixedly installed on described tail room converging portion (4) entrance Fixing big tail room flange (7) is bolted to connection.

Tail room for engine testsand gas extraction system the most according to claim 1, it is characterised in that described tail room is received A diameter of D of the section of holding back (4) entrance_w, convergency is α_wr；The diameter D of the straight sections (5) such as described tail room_wkp, a length of L_wkp；Described tail A diameter of D that room expansion segment (6) exports_wc, the angle of flare is α_wc；Described D_w, D_wkp, L_wkpMeet following equations group:

$M_w={\[\frac{2}{k-1}\left(\mathrm{\π}{\left(M_w\right)}^{\frac{-\left(k-1\right)}{k}}-1\right)\]}^{0.5}---\left(1\right);$

$\mathrm{\π}\left(M_w\right)=\frac{P_w}{P_{t5}}---\left(2\right);$

$D_w={\[{(1+\frac{k-1}{2}{M}_W^2)}^{\frac{k-1}{2(k-1)}}/0.5M_w{(k+1)}^{\frac{(k+1)}{2(k-1)}}\]}^{0.5}{d}_{4kp}---\left(3\right);$

${\stackrel{\‾}{P}}_{tws}={\[\frac{\left(k+1\right)M_W^2}{\left(k-1\right)M_w^2+2}\]}^{\frac{k}{k-1}}{\[\frac{k+1}{2{\mathrm{kM}}_w^2-k+1}\]}^{\frac{1}{k-1}}---\left(4\right);$

$q\left(M_w\right)=\frac{M_W{\left(0.5\left(k+1\right)\right)}^{\left(k+1\right)/2\left(k-1\right)}}{{\left(1+0.5\left(k-1\right){M_W}^2\right)}^{\left(k+1\right)/2\left(k-1\right)}}---\left(5\right);$

$D_{wkp}=d_{4kp}{\left(\frac{q\left(M_w\right)}{{\stackrel{\‾}{p}}_{tws}}\right)}^{0.5}---\left(6\right);$

L_wkp=4D_wkp(7)；

In above-mentioned equation group: M_w: tail room converging portion entrance Mach number；K: specific heat ratio；π(M_w): tail room converging portion entrance Mach number pair The static pressure answered and stagnation pressure ratio；P_w: the static pressure that tail room converging portion entrance Mach number is corresponding, unit is pa；P_t5: tail room converging portion enters The stagnation pressure that mouth Mach number is corresponding, unit is pa；D_w: the diameter of tail room converging portion entrance, unit is mm；d_4kp: electromotor venturi is straight Footpath, unit is mm；After the normal shock wave that tail room converging portion entrance Mach number is corresponding with normal shock wave before overall pressure tatio；q(M_w): tail The velocity coeffficient that room converging portion entrance Mach number is corresponding；D_wkp: the diameter of the straight sections such as tail room, unit is mm；L_wkp: the straight sections such as tail room Length, unit is mm；

Wherein, real ambient pressure when the static pressure that converging portion entrance Mach number in tail room is corresponding and supersonic speed electromotor high-altitude flight Identical, the exit Mach number pair of stagnation pressure corresponding to tail room converging portion entrance Mach number and the nozzle of supersonic speed electromotor The stagnation pressure answered is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, the engines tail of supersonic speed electromotor Nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed electromotor is high Real ambient pressure during empty flight, specific heat ratio and electromotor throat diameter are the known parameters that supersonic speed electromotor is intrinsic, Parameter in above-mentioned equation group: M_w, k, π (M_w), P_w, P_t5, W_w, d_4kp,q(M_w), D_wkp, L_wkpIt is in engine testsand In the electromotor of all tests, the parameter that the maximum electromotor of nozzle rate of discharge is corresponding.

Tail room for engine testsand gas extraction system the most according to claim 4, it is characterised in that described convergency Meet: 0 ＜ α_wr≤12°；The described angle of flare meets 0 ＜ α_wc≤12°。

6. according to the tail room for engine testsand gas extraction system described in claim 4 or 5, it is characterised in that described can Change a diameter of D of little tail room (10)_wx, described D_wxMeet following equations group:

$M_{wx}={\[\frac{2}{k-1}(\mathrm{\π}{\left(M_{wx}\right)}^{\frac{-(k-1)}{k}}-1)\]}^{0.5}---\left(8\right);$

$\mathrm{\π}\left(M_{wx}\right)=\frac{P_{wx}}{P_{t5x}}---\left(9\right);$

$D_{wx}={\[{(1+\frac{k-1}{2}{M}_{Wx}^2)}^{\frac{k-1}{2(k-1)}}/0.5M_{wx}{(k+1)}^{\frac{(k+1)}{2(k-1)}}\]}^{0.5}{d}_{4kpx}---\left(10\right);$

In above-mentioned equation group: M_wx: replaceable little tail chamber inlet Mach number；π(M_wx): replaceable little tail chamber inlet Mach number is corresponding Static pressure and stagnation pressure ratio；P_wx: the static pressure that replaceable little tail chamber inlet Mach number is corresponding, unit is pa；P_t5x: replaceable little tail room The stagnation pressure that entrance Mach number is corresponding, unit is pa；D_wx: replaceable little tail chamber inlet diameter, unit is mm；d_4kpx: electromotor tries In ride in the electromotor of all tests, starting of the electromotor in addition to the electromotor that nozzle rate of discharge is maximum Machine throat diameter, unit is mm；

Wherein, real environment pressure when the static pressure that replaceable little tail chamber inlet Mach number is corresponding and supersonic speed electromotor high-altitude flight Power is identical, the outlet Mach of stagnation pressure corresponding to replaceable little tail chamber inlet Mach number and the nozzle of supersonic speed electromotor The stagnation pressure that number is corresponding is identical, and the nozzle exit Mach number of supersonic speed electromotor is more than 1, starting of supersonic speed electromotor Tail nozzle exit Mach number, the stagnation pressure that the nozzle exit Mach number of supersonic speed electromotor is corresponding, supersonic speed is started During machine high-altitude flight in real ambient pressure, specific heat ratio and engine testsand in the electromotor of all tests, except starting The electromotor throat diameter of the electromotor beyond the electromotor of tail nozzle exit maximum flow is that supersonic speed electromotor is intrinsic Known parameters, the parameter in above-mentioned equation group: M_wx, π (M_wx), P_wx, P_t5x, D_wx, d_4kpx, it is all examinations in engine testsand In the electromotor tested, the parameter that supersonic speed electromotor in addition to the electromotor that nozzle rate of discharge is maximum is corresponding.

Tail room for engine testsand gas extraction system the most according to claim 3, it is characterised in that described little tail room The a length of L of cylinder (9)_wx, the length of described little tail room cylinder (9) meets 500mm≤L_wx≤600mm。

Tail room for engine testsand gas extraction system the most according to claim 4, it is characterised in that engines tail sprays The outlet of pipe (3) is L with the distance of the entrance section of tail room converging portion (4)_ww, the outlet of described nozzle (3) Cross section meets 100mm≤L with the distance of the entrance section of tail room converging portion (4)_ww≤150mm。

Tail room for engine testsand gas extraction system the most according to claim 8, it is characterised in that engines tail sprays The outlet of pipe (3) is 120mm with the distance of the entrance section of tail room converging portion (4).

Tail room for engine testsand gas extraction system the most according to claim 1, it is characterised in that described tail room The outlet of expansion segment connects injector or vacuum tank.