CN205991882U - Injector for engine testsand gas extraction system - Google Patents

Abstract

The utility model discloses a kind of injector for engine testsand gas extraction system, sequentially coaxially it is fixedly connected with low-pressure chamber according to by the flow direction of injection air-flow, changeover portion, blend converging portion, the straight sections such as blending, blend expansion segment, low pressure interior is sequentially coaxially fixedly connected with injection air-flow input section according to by the flow direction of injection air-flow, injection air-flow converging portion, the straight sections such as injection air-flow, injection air-flow expansion segment, low-pressure chamber, changeover portion, blend converging portion, the straight sections such as blending, blend expansion segment, injection air-flow input section, injection air-flow converging portion, the straight sections such as injection air-flow, injection air-flow expansion segment is hollow revolving body, injection air-flow input section is coaxial with low-pressure chamber, the outlet of the outlet of low-pressure chamber and injection air-flow expansion segment is in same vertical plane.Injector of the present utility model, injection performance is high, and then improves the efficiency of test, reduces experimentation cost.

Description

Injector for engine testsand gas extraction system

Technical field

This utility model is related to a kind of injector, especially a kind of injector for engine testsand gas extraction system.

Background technology

When in ground simulation electromotor high-altitude flight state, generally first electromotor is arranged in altitude simulation cabin, makes With air-extractor, altitude simulation cabin is carried out being evacuated and make the pressure in altitude simulation cabin and residing height during electromotor high-altitude flight The ambient pressure of degree is identical, then carries out engine ignition, carries out high-altitude flight simulation test, will 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 immediately starting Machine expellant gas discharge altitude simulation cabin, in prior art, are generally evacuated using injector, injector is to use higher pressure Injection airflow injection low pressure (or no press) by injection air-flow, complete the suction of injection air-flow by injection air-flow carry out blending injection or The device of conveying, due to injector without motion part, using reliability, is widely used in engine testsand gas extraction system；And for The injection portion of injection air-flow and the geometry in blending portion of blending injection, position relationship is provided to be the keys determining injector performance Factor, and for the injector of engine testsand gas extraction system in prior art, do not formed ripe, rational injection portion and Blending portion geometry each other, position relationship, lead to the injection degraded performance of injector, reduce the efficiency of test, simultaneously Increased experimentation cost.

Content of the invention

The purpose of this utility model is to overcome the defect of above-mentioned prior art presence to provide a kind of high injection The injector of energy.

The purpose of this utility model can be achieved through the following technical solutions：

A kind of injector for engine testsand gas extraction system, according to by the flow direction of injection air-flow sequentially coaxially Be fixedly connected with low-pressure chamber, changeover portion, blend converging portion, the straight section such as blend, blend expansion segment, described low pressure indoor according to being drawn The flow direction of stream of emanating sequentially coaxially is fixedly connected with injection air-flow input section, injection air-flow converging portion, and injection air-flow etc. is straight Section, injection air-flow expansion segment, described low-pressure chamber, changeover portion, blend converging portion, the straight section such as blending, blend expansion segment, injection air-flow Input section, injection air-flow converging portion, the straight section such as injection air-flow, injection air-flow expansion segment is hollow revolving body, described injection gas Stream input section is coaxial with described low-pressure chamber, and the outlet of described low-pressure chamber is existed with the outlet of described injection air-flow expansion segment Same vertical plane.

Further, described injection air-flow input section one end is fixedly connected with deflection cone, described deflection cone and described injection Air-flow input section is coaxial, and the summit of described deflection cone is on described low-pressure chamber entrance section.

Further, described injector includes injection airflow pipeline, described injection airflow pipeline one end and institute State injection air-flow input section to connect, the other end is connected with high-pressure air source.

Further, a diameter of D of the straight section such as described injection air-flow_akp1, a diameter of D of described injection air-flow expansion segment_a2, D_akp1And D_a2Meet following equations group：

P_am1=P_tb1(6)

In above-mentioned equation group：D_akp1：The diameter of the straight sections such as injection air-flow, unit is mm；S_akp1：The straight sections such as injection air-flow Area, unit is mm²；G_a1：The flow of injection air-flow, unit is kg/s；T_ta1：The temperature of injection air-flow, unit is K；P_takp1： Stagnation pressure in the straight sections such as injection air-flow, unit is Mpa；P_tam1：Injection air-flow is in injection air-flow expansion segment outlet Mach number Corresponding stagnation pressure, unit is Mpa；δ₁：Injection air-flow is in the total pressure recovery coefficient of injection air-flow expansion segment；P_am1：Injection air-flow exists The corresponding static pressure of injection air-flow expansion segment outlet Mach number, unit is Mpa；M_a1：Injection air-flow is in injection air-flow expansion segment Outlet Mach number；π(M_a1)：Injection air-flow is in the corresponding static pressure of injection air-flow expansion segment outlet Mach number and stagnation pressure Than；k：Specific heat ratio；P_tb1：By injection air-flow stagnation pressure, unit is Mpa；G_b1：By the flow of injection air-flow, unit is kg/s；n₁：Draw Penetrate coefficient；D_a2：The diameter of injection air-flow expansion segment, unit is mm；S_a2：The area of injection air-flow expansion segment, unit is mm²；q (M_a1)：Injection air-flow is in the corresponding velocity coeffficient of injection air-flow expansion segment outlet Mach number；Wherein, injection air-flow is in injection Air-flow expansion segment outlet Mach number is more than 1, and described injection air-flow is in injection air-flow expansion segment outlet Mach number by That knows determines by injection air-flow stagnation pressure with by the flow of injection air-flow, and described mass ratio of induced-to-inducing air is expanded in injection air-flow by injection air-flow Section outlet Mach number and the stagnation temperature of known injection air-flow and determined by the stagnation temperature of injection air-flow.

Further, a diameter of D of the straight section such as described blending_ckp1, length is L_ckp1；Blend a diameter of D of converging portion_c11, Convergency is α₁, length is L_c11；Blend a diameter of D of expansion segment_c12, the angle of flare is α₂, length is L_c12；D_ckp1, L_ckp1, D_c11, α₁₁, L_c11, D_c12, α₁₂, L_c12Meet following equations group：

S_ckp1=S_akp1×f_ackp1(12)

L_ckp1=4 × D_ckp1(13)

S_c11=1.95 × S_ckp1(15)

D_c11=D_c12(16)

In above-mentioned equation group：D_ckp1：The diameter of the straight sections such as blending, unit is mm；S_ckp1：The area of the straight sections such as blending, unit For mm²；f_ackp1：The area ratio of straight section and the straight sections such as injection airflow injection air-flow such as blend；L_ckp1：The length of the straight sections such as blending, Unit is mm；D_c11：Blend the diameter of converging portion, unit is mm；S_c11：Blend the area of converging portion, unit is mm²；D_c12：Mix The diameter of mixed expansion segment, unit is mm；L_c11：Blend the length of converging portion, unit is mm；α₁₁：Blend the convergency of converging portion, Unit is ° L_c12：Blend the length of expansion segment, unit is mm；α₁₂：Blend expansion segment the angle of flare, unit be °；Wherein, blend Deng straight section and the straight sections such as injection airflow injection air-flow area than by injection air-flow in injection air-flow expansion segment outlet Mach Number determines.

Further, the described convergency blending converging portion meets：4°≤α₁₁≤ 5 °, the described angle of flare blending expansion segment Meet：4°≤α₁₂≤5°.

Further, the angle of flare of the described convergency blending converging portion and blending expansion segment is 4.4 °.

Further, a diameter of D of described low-pressure chamber₁, the diameter of described low-pressure chamber meets equation：D₁=1.05 × D_c11, Wherein, D₁Unit be mm.

Further, the length of described changeover portion is S₁, the length of described changeover portion meets equation：S₁=D₁-D_c11, its In, S₁Unit be mm.

Further, described blending expansion segment outlet connects air-extractor or direct and atmosphere.

Compared with prior art, the injector for engine testsand gas extraction system described in the utility model, passes through Setting changeover portion, and by the outlet of the outlet of low-pressure chamber and injection air-flow expansion segment in same vertical plane, simultaneously bright The really diameter of the straight section such as injection air-flow, injection air-flow expansion segment diameter, straight section diameter, the length such as blends；Blend converging portion straight Footpath, convergency, length；Blend expansion segment diameter, the angle of flare, length；Injection air-flow expansion segment diameter, low-pressure chamber diameter, transition Geometrical relationship between segment length and/or numerical value, improve the injection performance of injector.

Brief description

With reference to the accompanying drawings and detailed description this utility model is further described.

Fig. 1 is used for the schematic diagram of the injector of engine testsand gas extraction system for this utility model.

Fig. 2 is used for the schematic diagram of the low-pressure chamber of engine testsand gas extraction system injector for this utility model.

Fig. 3 is used for the schematic diagram of the blending section of engine testsand gas extraction system injector for this utility model.

Specific embodiment

Referring to Fig. 1-3, a kind of injector for engine testsand gas extraction system, according to by the flowing side of injection air-flow To being sequentially coaxially fixedly connected with low-pressure chamber 1, changeover portion 2, blend converging portion 3, the straight section 4 such as blending, blend expansion segment 5, described Sequentially coaxially it is fixedly connected with injection air-flow input section 9 according to by the flow direction of injection air-flow, injection air-flow is received in low-pressure chamber 1 Hold back section 6, the straight section such as injection air-flow 7, injection air-flow expansion segment 8, described low-pressure chamber 1, changeover portion 2, blend converging portion 3, blend etc. Straight section 4, blends expansion segment 5, injection air-flow input section 9, injection air-flow converging portion 6, the straight section such as injection air-flow 7, injection air-flow expands Open section 8 and be hollow revolving body, described injection air-flow input section 9 is coaxial with described low-pressure chamber 1, and the outlet of described low-pressure chamber 1 cuts The outlet of face and described injection air-flow expansion segment 8 is in same vertical plane.

Preferably, described injection air-flow input section 9 one end is fixedly connected with deflection cone 10, and described deflection cone 10 is drawn with described Emanating, stream input section 9 is coaxial, and the summit of described deflection cone 10 is on described low-pressure chamber 1 entrance section.

Preferably, described injector includes injection airflow pipeline 11, described injection airflow pipeline 11 one end with Described injection air-flow input section 9 connects, and the other end is connected with high-pressure air source.

A diameter of D of the straight sections 7 such as described injection air-flow_akp1, a diameter of D of described injection air-flow expansion segment 8_a2, D_akp1With D_a2Meet following equations group：

P_am1=P_tb1(6)

In above-mentioned equation group：D_akp1：The diameter of the straight sections such as injection air-flow, unit is mm；S_akp1：The straight sections such as injection air-flow Area, unit is mm²；G_a1：The flow of injection air-flow, unit is kg/s；T_ta1：The temperature of injection air-flow, unit is K；P_takp1： Stagnation pressure in the straight sections such as injection air-flow, unit is Mpa；P_tam1：Injection air-flow is in injection air-flow expansion segment outlet Mach number Corresponding stagnation pressure, unit is Mpa；δ₁：Injection air-flow is in the total pressure recovery coefficient of injection air-flow expansion segment；P_am1：Injection air-flow exists The corresponding static pressure of injection air-flow expansion segment outlet Mach number, unit is Mpa；M_a1：Injection air-flow is in injection air-flow expansion segment Outlet Mach number；π(M_a1)：Injection air-flow is in the corresponding static pressure of injection air-flow expansion segment outlet Mach number and stagnation pressure Than；k：Specific heat ratio；P_tb1：By injection air-flow stagnation pressure, unit is Mpa；G_b1：By the flow of injection air-flow, unit is kg/s；n₁：Draw Penetrate coefficient；D_a2：The diameter of injection air-flow expansion segment, unit is mm；S_a2：The area of injection air-flow expansion segment, unit is mm²；q (M_a1)：Injection air-flow is in the corresponding velocity coeffficient of injection air-flow expansion segment outlet Mach number；Wherein, injection air-flow is in injection Air-flow expansion segment outlet Mach number is more than 1, and described injection air-flow is in injection air-flow expansion segment outlet Mach number by That knows determines by injection air-flow stagnation pressure with by the flow of injection air-flow, and described mass ratio of induced-to-inducing air is expanded in injection air-flow by injection air-flow Section outlet Mach number and the stagnation temperature of known injection air-flow and determined by the stagnation temperature of injection air-flow.

Preferably, a diameter of D of the straight section 4 such as described blending_ckp1, length is L_ckp1；Blend a diameter of D of converging portion 3_c11, Convergency is α₁, length is L_c11；Blend a diameter of D of expansion segment 5_c12, the angle of flare is α₂, length is L_c12；D_ckp1, L_ckp1, D_c11, α₁₁, L_c11, D_c12, α₁₂, L_c12Meet following equations group：

S_ckp1=S_akp1×f_ackp1(12)

L_ckp1=4 × D_ckp1(13)

S_c11=1.95 × S_ckp1(15)

D_c11=D_c12(16)

In above-mentioned equation group：D_ckp1：The diameter of the straight sections such as blending, unit is mm；S_ckp1：The area of the straight sections such as blending, unit For mm²；f_ackp1：The area ratio of straight section and the straight sections such as injection airflow injection air-flow such as blend；L_ckp1：The length of the straight sections such as blending, Unit is mm；D_c11：Blend the diameter of converging portion, unit is mm；S_c11：Blend the area of converging portion, unit is mm²；D_c12：Mix The diameter of mixed expansion segment, unit is mm；L_c11：Blend the length of converging portion, unit is mm；α₁₁：Blend the convergency of converging portion, Unit is ° L_c12：Blend the length of expansion segment, unit is mm；α₁₂：Blend expansion segment the angle of flare, unit be °；Wherein, blend Deng straight section and the straight sections such as injection airflow injection air-flow area than by injection air-flow in injection air-flow expansion segment outlet Mach Number determines.

Preferably, the described convergency blending converging portion meets：4°≤α₁₁≤ 5 °, the described angle of flare blending expansion segment is completely Foot：4°≤α₁₂≤5°.

Preferably, the angle of flare of the described convergency blending converging portion and blending expansion segment is 4.4 °.

Preferably, a diameter of D of described low-pressure chamber 1₁, the diameter of described low-pressure chamber 1 meets equation：D₁=1.05 × D_c11, Wherein, D₁Unit be mm.

Preferably, the length of described changeover portion 2 is S₁, the length of described changeover portion 2 meets equation：S₁=D₁-D_c11, its In, S₁Unit be mm.

Preferably, described blending expansion segment 5 outlet connects air-extractor or direct and atmosphere.

The operation principle of injector described in the utility model is：Gases at high pressure in high-pressure air source are conveyed by injection air-flow Pipeline enters injection air-flow input section, and described gases at high pressure are through the injection air-flow converging portion of class Laval nozzle shape, injection The straight sections such as air-flow, form supersonic speed high pressure draught after injection air-flow expansion segment, and then injection enters along deflection cone from low pressure chamber inlet The low pressure entering by injection air-flow, the supersonic speed injection air-flow of high pressure and low pressure by injection air-flow in class Laval nozzle shape Blending converging portion, the straight section such as blend, blend expansion segment and be sufficiently mixed, improve by the static pressure of injection air-flow, after blending When mixed airflow static pressure is more than or equal to 0.11Mpa, injector outlet can directly and atmosphere, and mixed airflow after blending is quiet When pressure is less than 0.11Mpa, injector outlet still needs to reconnect one-level injector.

Finally illustrate, above example is merely to illustrate the technical solution of the utility model and unrestricted, although ginseng According to preferred embodiment, this utility model is described in detail, it will be understood by those of skill in the art that can be to this reality Modified and equivalent substitute with new technical scheme, the objective without deviating from technical solutions of the utility model and scope, its All should cover in the middle of right of the present utility model.

Claims (10)

1. a kind of injector for engine testsand gas extraction system is it is characterised in that described injector is according to by injection gas The flow direction of stream is sequentially coaxially fixedly connected with low-pressure chamber (1), changeover portion (2), blends converging portion (3), the straight section such as blending (4), blend expansion segment (5), draw according to being sequentially coaxially fixedly connected with by the flow direction of injection air-flow in described low-pressure chamber (1) Emanate and flow input section (9), injection air-flow converging portion (6), the straight section such as injection air-flow (7), injection air-flow expansion segment (8) is described low Pressure chamber (1), changeover portion (2), blend converging portion (3), the straight section (4) such as blending, blend expansion segment (5), injection air-flow input section (9), injection air-flow converging portion (6), the straight section such as injection air-flow (7), injection air-flow expansion segment (8) is hollow revolving body, described Injection air-flow input section (9) is coaxial with described low-pressure chamber (1), and the outlet of described low-pressure chamber (1) is expanded with described injection air-flow The outlet opening section (8) is in same vertical plane.

2. injector according to claim 1 is it is characterised in that described injection air-flow input section (9) one end is fixedly connected There is deflection cone (10), described deflection cone (10) is coaxial with described injection air-flow input section (9), the summit of described deflection cone (10) exists On described low-pressure chamber (1) entrance section.

3. injector according to claim 1 is it is characterised in that include injection airflow pipeline (11), described injection Airflow pipeline (11) one end is connected with described injection air-flow input section (9), and the other end is connected with high-pressure air source.

4. injector according to claim 1 is it is characterised in that a diameter of D of the straight section such as described injection air-flow (7)_akp1, A diameter of D of described injection air-flow expansion segment (8)_a2, described D_akp1And D_a2Meet following equations group：

$D_{akp1}=\sqrt{\frac{4S_{akp1}}{3.14}}---\left(1\right)$

$S_{akp1}=\frac{G_{a1}\×\sqrt{T_{ta1}}}{0.0404\×P_{takp1}}---\left(2\right)$

$P_{takp1}=\frac{P_{tam1}}{{\mathrm{\δ}}_1}---\left(3\right)$

$P_{tam1}=\frac{P_{am1}}{\mathrm{\π}\left(M_{a1}\right)}---\left(4\right)$

$\mathrm{\π}\left(M_{a1}\right)={(1+\frac{k-1}{2}{M_{a1}}^2)}^{-\frac{k}{k-1}}---\left(5\right)$

P_am1=P_tb1(6)

$G_{a1}=\frac{G_{b1}}{n_1}---\left(1\right)$

$D_{a2}=\sqrt{\frac{4S_{a2}}{3.14}}---\left(8\right)$

$S_{a2}=\frac{S_{akp1}}{{\mathrm{\δ}}_1*q\left(M_{a1}\right)}---\left(9\right)$

$q\left(M_{a1}\right)=\frac{M_{a1}{\left(0.5\right(k+1\left)\right)}^{(k+1)/2(k-1)}}{{(1+0.5(k-1\left){M_{a1}}^2\right)}^{(k+1)/2(k-1)}}---\left(10\right)$

In above-mentioned equation group：D_akp1：The diameter of the straight sections such as injection air-flow, unit is mm；S_akp1：The area of the straight sections such as injection air-flow, Unit is mm²；G_a1：The flow of injection air-flow, unit is kg/s；T_ta1：The temperature of injection air-flow, unit is K；P_takp1：Injection gas Stagnation pressure in the straight sections such as stream, unit is Mpa；P_tam1：Injection air-flow is corresponding in injection air-flow expansion segment outlet Mach number Stagnation pressure, unit is Mpa；δ₁：Injection air-flow is in the total pressure recovery coefficient of injection air-flow expansion segment；P_am1：Injection air-flow is in injection gas The corresponding static pressure of stream expansion segment outlet Mach number, unit is Mpa；M_a1：Injection air-flow cuts in the outlet of injection air-flow expansion segment Face Mach number；π(M_a1)：Injection air-flow is in the corresponding static pressure of injection air-flow expansion segment outlet Mach number and overall pressure tatio；k：Than Ratio of specific heat；P_tb1：By injection air-flow stagnation pressure, unit is Mpa；G_b1：By the flow of injection air-flow, unit is kg/s；n₁：Mass ratio of induced-to-inducing air； D_a2：The diameter of injection air-flow expansion segment, unit is mm；S_a2：The area of injection air-flow expansion segment, unit is mm²；q(M_a1)：Draw Emanate stream in the corresponding velocity coeffficient of injection air-flow expansion segment outlet Mach number；Wherein, injection air-flow expands in injection air-flow Open section outlet Mach number and be more than 1, described injection air-flow is in injection air-flow expansion segment outlet Mach number by known quilt Injection air-flow stagnation pressure and being determined by the flow of injection air-flow, described mass ratio of induced-to-inducing air is exported in injection air-flow expansion segment by injection air-flow The stagnation temperature of section Mach number and known injection air-flow and being determined by the stagnation temperature of injection air-flow.

5. injector according to claim 4 is it is characterised in that a diameter of D of the straight section such as described blending (4)_ckp1, length For L_ckp1；Blend a diameter of D of converging portion (3)_c11, convergency is α₁, length is L_c11；Described blend expansion segment (5) a diameter of D_a2, the angle of flare is α₂, length is L_c12；Described D_ckp1, L_ckp1, D_c11, α₁₁, L_c11, D_c12, α₁₂, L_c12Meet following equations group：

$D_{ckp1}=\sqrt{\frac{4S_{ckp1}}{3.14}}---\left(11\right)$

S_ckp1=S_akp1×f_ackp1(12)

L_ckp1=4 × D_ckp1(13)

$D_{c11}=\sqrt{\frac{4S_{c11}}{3.14}}---\left(14\right)$

S_c11=1.95 × S_ckp1(15)

D_c11=D_c12(16)

$L_{c11}=\frac{\frac{1}{2}(D_{c11}-D_{ckp1})}{\tan \frac{{\mathrm{\α}}_{11}}{2}}---\left(17\right)$

$L_{c12}=\frac{\frac{1}{2}(D_{c12}-D_{ckp1})}{\tan \frac{{\mathrm{\α}}_{12}}{2}}---\left(18\right)$

In above-mentioned equation group：D_ckp1：The diameter of the straight sections such as blending, unit is mm；S_ckp1：The area of straight section such as blend, unit is mm²；f_ackp1：The area ratio of straight section and the straight sections such as injection airflow injection air-flow such as blend；L_ckp1：The length of the straight sections such as blending, single Position is mm；D_c11：Blend the diameter of converging portion, unit is mm；S_c11：Blend the area of converging portion, unit is mm²；D_c12：Blend The diameter of expansion segment, unit is mm；L_c11：Blend the length of converging portion, unit is mm；α₁₁：Blend the convergency of converging portion, single Position is ° L_c12：Blend the length of expansion segment, unit is mm；α₁₂：Blend expansion segment the angle of flare, unit be °；Wherein, blend etc. The area of straight section and the straight sections such as injection airflow injection air-flow than by injection air-flow in injection air-flow expansion segment outlet Mach number Determine.

6. injector according to claim 5 is it is characterised in that the convergency of described blending converging portion meets：4°≤α₁₁ ≤ 5 °, the described angle of flare blending expansion segment meets：4°≤α₁₂≤5°.

7. injector according to claim 5 it is characterised in that the convergency of described blending converging portion and blend expansion segment The angle of flare be 4.4 °.

8. injector according to claim 5 is it is characterised in that a diameter of D of described low-pressure chamber (1)₁, described low-pressure chamber (1) diameter meets equation：D₁=1.05 × D_c11, wherein, D₁Unit be mm.

9. injector according to claim 8 is it is characterised in that the length of described changeover portion (2) is S₁, described changeover portion (2) length meets equation：S₁=D₁-D_c11, wherein, S₁Unit be mm.

10. injector according to claim 1 is it is characterised in that described blending expansion segment (5) outlet connects air-extractor Or direct and atmosphere.