CN207701245U - A kind of big flow liquid conveying system frequency run system - Google Patents
A kind of big flow liquid conveying system frequency run system Download PDFInfo
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- CN207701245U CN207701245U CN201721781163.3U CN201721781163U CN207701245U CN 207701245 U CN207701245 U CN 207701245U CN 201721781163 U CN201721781163 U CN 201721781163U CN 207701245 U CN207701245 U CN 207701245U
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- conveying system
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Abstract
The utility model is related to a kind of big flow liquid conveying system frequency run system, solves the problems, such as that existing big flow liquid conveying system frequency run lacks and be suitable for the high fluid pulsation excitation system of wide frequency ranges, excitation energy.System includes testing stand, liquid conveying system, waterpower excitation system, accumulator and orifice union；Liquid conveying system includes sequentially connected main pipe, oxidant main valve, combustion chamber oxidant head cavity and ejector filler；Waterpower excitation system includes the first throttle circle and the second throttle being connected on driving source pipeline, and bypass line is provided between first throttle circle and the second throttle, and rotating disc type fluctuation pressure driver is arranged on bypass line；Testing stand is connected with main pipe by testing stand main line, and accumulator and orifice union are arranged on testing stand main line；The outlet of waterpower excitation system is connected in the combustion chamber head cavity or main line of liquid conveying system.
Description
Technical field
The utility model is related to liquid-propellant rocket engine fields, and in particular to a kind of big flow liquid conveying system frequency is special
Property pilot system, for analyze liquid-propellant rocket engine pump after liquid conveying system frequency response characteristic.
Background technology
Liquid-propellant rocket engine propellant liquid conveying system is complex, in engineering practice find there are it is a variety of with push away
It is asked into the relevant dynamics problem of agent liquid conveying system frequency characteristic, such as the oscillation of the POGO problems, valve automation of low frequency
The coupled oscillations combustion problem of topic, fuel assembly and liquid conveying system, the dynamic spray characteristic issues of ejector filler, if to above-mentioned
Problem is studied, and the dynamic test for carrying out different frequency scope is needed, and the frequency to study complex fluid transport system is rung
Answer characteristic.Since engine liquid body conveying system is complicated, the especially pump pressure type rocket engine of big flow contains pipe
Multiple components such as road, valve, thrust chamber head cavity, ejector filler, the experiment of such fluid frequency response characteristic are generally difficult to implement, a side
Face, which is the absence of, is suitable for the high fluid pulsation excitation system of wide frequency ranges, excitation energy；On the other hand, the fluid liquid of big flow
Body conveying system Dynamic boundary condition is difficult to simulate on liquid flow test platform, especially to acoustics closed end inlet boundary condition
Simulation lacks guiding method；In addition, how flow, the pressure parameter of Selection experiment platform, improve test data signal-to-noise ratio and
Accuracy and prodigious problem.
Utility model content
The purpose of this utility model is to solve existing big flow liquid conveying system frequency run and lack to be suitable for width
The fluid body transport system dynamics boundary of the high fluid pulsation excitation system of frequency range, excitation energy and big flow
Condition provides a kind of big flow liquid conveying system frequency run system the problems such as being difficult to simulate on liquid flow test platform
System.
The technical solution of the utility model is：
A kind of big flow liquid conveying system frequency run system, including testing stand, liquid conveying system, waterpower swash
Vibrating system, accumulator and orifice union；The liquid conveying system includes sequentially connected main pipe, oxidant main valve, burning
Room oxidant head cavity and ejector filler；The waterpower excitation system includes the first throttle circle and second being connected on driving source pipeline
Throttle is provided with bypass line, the setting of rotating disc type fluctuation pressure driver between the first throttle circle and the second throttle
On bypass line；The testing stand is connected with main pipe by testing stand main line, and the accumulator and orifice union are all provided with
It sets on testing stand main line；The waterpower excitation system outlet is connected to the combustion chamber oxidant head cavity of liquid conveying system
In.
Further, the liquid conveying system arranges fluctuation pressure measuring point along journey.
Further, the liquid conveying system is at least 4 along the quantity of journey fluctuation pressure measuring point.
Further, the liquid conveying system along the quantity of journey fluctuation pressure measuring point at 10 or more.
Further, the branch line diameter for connecting accumulator is identical as the caliber of testing stand main line.
Meanwhile the utility model also provides a kind of experiment based on big flow liquid conveying system frequency run system
Method includes the following steps：
1) liquid conveying system is configured：Liquid conveying system includes sequentially connected main pipe, oxidant main valve, combustion chamber
Oxidant head cavity and ejector filler, and in liquid conveying system fluctuation pressure measuring point is arranged along journey；
2) Selection experiment platform main road flow rate working conditions：If testing stand ability meets liquid conveying system full flow ability,
Testing stand main flow is the working flow of liquid conveying system within the engine；If testing stand ability cannot meet full flow energy
Power, then it is abundant turbulence state that Selection experiment platform main flow, which meets inside liquid conveying system,；
3) boundary condition of liquid conveying system within the engine is simulated on testing stand：Liquid conveying system arrival end mould
It is intended to be acoustics closed end boundary, liquid conveying system outlet end is modeled as acoustics beginning boundary；
4) it calculates and swashs using rotating disc type fluctuation pressure driver according to the frequency range of testing stand main road flow and setting
The average flow rate and pressure needed for source capsule road are encouraged, and builds the waterpower excitation system for generating medium, high frequency fluctuation pressure signal, in water
Oscillatory pressure pick-up measuring point and steady state pressure Sensor are arranged in power excitation system outlet end；
5) outlet of waterpower excitation system is connected in the combustion chamber oxidant head cavity of liquid conveying system；
6) accumulator is set on the testing stand main line of liquid conveying system entrance boundary upstream, ensures pressure accumulation in experiment
Device includes the air cushion of 1/5~1/3 total measurement (volume)；
7) testing stand main road leads to liquid, and flow is incrementally increased to the flow rate working conditions of design；
8) waterpower excitation system leads to liquid, the electrical power of rotating disc type fluctuation pressure driver, by waterpower excitation system stable state
Pressure gradually increases to setting value；
9) the motor control voltage of rotating disc type fluctuation pressure driver is altered in steps so that the fluctuation pressure excitation frequency of generation
Rate is continuously enlarged from 0Hz to the highest frequency value studied, then from highest frequency value linear reduction to 0Hz, is constituted one and is swept
Frequency Energizing cycle completes the frequency run to research object.
Further, liquid conveying system is at least 4 along the quantity of journey fluctuation pressure measuring point in the step 1).
Further, in the step 1) liquid conveying system along journey fluctuation pressure measuring point quantity at 10 or more.
Further, in the step 2), the minimum of testing stand main flow is：Meet in liquid conveying system main pipe
Reynolds number be more than 105。
Further, in the step 3), liquid conveying system arrival end is modeled as acoustics closed end boundary, and big impedance is arranged
Orifice union, when not generating cavitation situation, the impedance absolute value of orifice union is more than the characteristic impedance 2 of downstream main pipe
Times；Liquid conveying system outlet end is modeled as acoustics beginning boundary, and directly logical extraneous or connection circulation area expands 5 times or more
Fixation pressure container in.
Further, in the step 4), the average flow rate of driving source pipeline be testing stand main line flow 8%~
15%, driving source loine pressure is more than main road pressure 2 times or more.
Further, in the step 6), accumulator is set on testing stand main line, the branch line for connecting accumulator is straight
Diameter is identical as testing stand main line caliber.
Further, in the step 9), swept frequency excitation frequency is to be continuously enlarged from 0Hz to highest frequency value, then from most
High frequency values are subsequently reduced to 0Hz, frequency variation rate≤12Hz/s.
The advantages of the utility model is：
1. frequency-swept range is wide：It is conventionally used to the piston of carrier rocket liquid propellant liquid conveying system POGO experiments
Formula excitation system frequency range is within 50Hz, and the reciprocating motion of piston needs the powerful energy, and it is defeated cannot to meet liquid
Send the needs that system is studied within the scope of acoustic resonance.The utility model uses rotating disc type fluctuation pressure driver, frequency range
Basic, normal, high frequency can be completely covered, frequency range is more than 1000Hz, has reached liquid conveying system acoustic resonance range.
2. excitation energy is sufficient, signal-to-noise ratio is high：Tradition is applied to the loud speaker class driving source of the gas operatic tunes, acoustic pressure too small
It is suitable for the gas of density and viscosity all very littles, is applied to the driving source range of flow of single injector dynamic spray test in 100g/s
Within, for the big flow liquid-propellant rocket engine liquid conveying system of 10kg/s magnitudes, the energy of driving source is obviously insufficient.For
The sufficiently high excitation energy of guarantee and signal-to-noise ratio, the utility model using big flow rotating disc type fluctuation pressure driver device, increase
Adding system throttle, the mode for improving driving source steady state pressure, main road increase accumulator achieve the purpose that raising signal-to-noise ratio, and
The proper ratio range of excitation source flux and mainstream flow is determined.
3. the feasible simulation of Dynamic boundary condition：The utility model provides the liquid delivery system that simulation is needed on testing stand
It unites Dynamic boundary condition, it is proposed that analogy method, the orifice union of big impedance is arranged in liquid conveying system entrance, and (impedance is exhausted
Should be greater than 2 times of the characteristic impedance of downstream main pipe to value), to simulate entrance as acoustics closed end boundary；Liquid conveying system exports
Directly logical extraneous (or fixation pressure container of 5 times of circulation area of connection or more), with simulation outlet for acoustics beginning boundary.
4. the process of proposition, the continuous swept frequency excitation method of backhaul, in primary experiment, swept frequency excitation frequency continuously increases from 0Hz
The big highest frequency value that need to extremely study, then it is subsequently reduced to 0Hz from highest frequency value, it can disposably complete entire frequency range
Interior swept frequency excitation, test efficiency are high, and pass through the repeatability of the data comparison test data into, backhaul.
Description of the drawings
Fig. 1 is the liquid flow test system construction drawing of the utility model；
Fig. 2 is the utility model liquid conveying system structure chart；
Fig. 3 is the utility model waterpower excitation system structure chart.
Fig. 4 is the flow diagram of the utility model method；
Reference numeral：1- liquid conveying systems, 2- waterpower excitation systems, 3- orifice unions, 4- accumulators, 5- first throttles
Circle, 6- main pipes, 7- oxidant main valves, the combustion chambers 8- oxidant head cavity, 9- ejector fillers, 10- driving source pipelines, 11- second are saved
Stream circle, 12- rotating disc type fluctuation pressure drivers, 13- bypass lines, 14- testing stands, 15- testing stand main lines.
Specific implementation mode
The technical solution of the utility model is clearly and completely described with reference to the accompanying drawings of the specification.
The utility model provides the system and method for carrying out frequency run to big flow liquid conveying system, is used for
After exploration rocket engine pump propellant liquid conveying system medium, high frequency range frequency response characteristic, it is defeated to obtain liquid
Send the acoustic resonant frequencies and the vibration shape of system.The utility model gives the selection model of liquid conveying system after rocket motor pump
It encloses, test flow operating mode, boundary condition imitation principle, waterpower excitation system design and duty parameter, accumulator setting requirements, arteries and veins
Dynamic pressure point layout, experiment process and swept frequency excitation method, can completely cover basic, normal, high frequency, and frequency range is more than
1000Hz has reached liquid conveying system acoustic resonance range.The utility model confirms that excitation energy is sufficient, believes through overtesting
It makes an uproar than high, the big flow liquid-propellant rocket engine liquid conveying system of suitable 10kg/s magnitudes, after obtaining certain h type engine h pump
Resonant frequency and fluctuation pressure vibration shape distribution, data redundancy of the liquid conveying system within 1200Hz are good.
A kind of big flow liquid conveying system frequency run system as shown in Figure 1, Figure 2, Figure 3 shows, including testing stand
14, liquid conveying system 1, waterpower excitation system 2, accumulator 4 and orifice union 3；Liquid conveying system 1 includes sequentially connected
Main pipe 6, oxidant main valve 7, combustion chamber oxidant head cavity 8 and ejector filler 9；Waterpower excitation system 2 includes being connected to driving source
First throttle circle 5 on pipeline 10 and the second throttle 11, bypass pipe is provided between first throttle circle 5 and the second throttle 11
Road 13, rotating disc type fluctuation pressure driver 12 are arranged on bypass line 13；Testing stand 14 and main pipe 6 are responsible for by testing stand
Road 15 connects, and accumulator 4 and orifice union 3 are arranged on testing stand main line 15；The outlet of waterpower excitation system 2 is connected to liquid
In the combustion chamber oxidant head cavity 8 of body conveying system 1.Further, the liquid conveying system is surveyed along journey arrangement fluctuation pressure
Point.Liquid conveying system arranges fluctuation pressure measuring point along journey.Liquid conveying system is at least 4 along the quantity of journey fluctuation pressure measuring point
It is a, liquid conveying system along journey fluctuation pressure measuring point quantity at 10 or more, connect the branch line diameter of accumulator and examination
The caliber for testing platform main line is identical.
As shown in figure 4, the utility model additionally provides a kind of big flow liquid conveying system frequency run system
Test method, the frequency for carrying out medium, high frequency range to propellant liquid conveying system after liquid-propellant rocket engine high-capacity pump are rung
It should test, to obtain the acoustic resonant frequencies and the vibration shape of liquid conveying system, include the following steps：
1) it includes being sequentially connected to select true liquid-propellant rocket engine propellant liquid conveying system, liquid conveying system
Main pipe, oxidant main valve, combustion chamber oxidant head cavity and ejector filler, and liquid conveying system along journey arrange fluctuation pressure
Measuring point；The quantity of fluctuation pressure measuring point is at least 4, preferably at 10 or more；
2) Selection experiment platform main road flow rate working conditions：If testing stand ability meets liquid conveying system full flow ability,
Testing stand main flow is the working flow of liquid conveying system within the engine；If testing stand ability cannot meet full flow energy
Power, then it is abundant turbulence state that Selection experiment platform main flow, which need to meet inside liquid conveying system,；Testing stand main flow it is minimum
Value is that the Reynolds number met in liquid conveying system main pipe is more than 105；
3) boundary condition of liquid conveying system within the engine is simulated on liquid flow test platform：Liquid conveying system entrance
End is modeled as acoustics closed end boundary, the orifice union of big impedance is arranged, when not generating cavitation situation, the impedance of orifice union is exhausted
To being worth 2 times of the characteristic impedance more than downstream main pipe；Liquid conveying system outlet end is modeled as acoustics beginning boundary, directly logical outer
Boundary or connection circulation area expand in 5 times or more of fixation pressure container；
4) excitation is calculated using rotating disc type fluctuation pressure driver according to the frequency range of experiment main road flow and research
Average flow rate needed for source capsule road and pressure, and the waterpower excitation system for generating medium, high frequency fluctuation pressure signal is built, in waterpower
Oscillatory pressure pick-up measuring point and steady state pressure Sensor are arranged in excitation system outlet end；The average flow rate of driving source pipeline
It is the 8%~15% of mainstream flow, driving source loine pressure is more than main road pressure 2 times or more；
5) outlet of waterpower excitation system is connected to the liquid line of research object (big flow complex fluid transport system)
Or in fuel assembly head cavity；
6) accumulator of big volume is set on the testing stand main line of liquid conveying system entrance boundary upstream, in experiment
Ensure the air cushion that accumulator includes 1/5~1/3 total measurement (volume)；Connect the branch line diameter and testing stand main line caliber of accumulator
It is identical；
7) testing stand main road leads to liquid, and flow is incrementally increased to the flow rate working conditions of setting；
8) waterpower excitation system leads to liquid, the electrical power of rotating disc type pulsation pressure generator, by waterpower excitation system stable state
Pressure gradually increases to design value；
9) be altered in steps fluctuation pressure driver motor control voltage so that the fluctuation pressure driving frequency of generation from
0Hz is continuously enlarged to the highest frequency value studied, then from highest frequency value linear reduction to 0Hz, is constituted a frequency sweep and is swashed
It encourages the period, that is, completes the frequency run to research object, frequency variation rate≤12Hz/s.
In order to study the frequency characteristic of liquid conveying system after certain type big flow liquid-propellant rocket engine oxidant pump, use
Tthe utility model system has carried out liquid conveying system after this pump the frequency run of medium, high frequency range, the utility model
Steps are as follows for specific embodiment：
1) it includes sequentially connected leading to select liquid-propellant rocket engine propellant liquid conveying system, liquid conveying system
Pipe, oxidant main valve, combustion chamber oxidant head cavity and ejector filler, and in liquid conveying system fluctuation pressure measuring point is arranged along journey；
9 fluctuation pressure measuring points are arranged along journey, 3 fluctuation pressure measuring points are arranged in burning oxygen head cavity, in spray ante-chamber pair in oxygen main pipe
Claim arrangement 2 fluctuation pressure measuring points；
2) since the full flow of liquid conveying system is very big, testing stand carries out drop flow simulation, Selection experiment platform main flow
For 25kg/s, it is 3.31 × 10 to calculate Reynolds number in oxygen main pipe5, meet abundant turbulence state；
3) boundary condition of liquid conveying system within the engine is simulated on testing stand：In liquid conveying system arrival end
High impedance orifice union is installed, it is to simulate acoustics closed end boundary (i.e. flow pulsation amount is 0), ejector filler outlet end is directly logical outer
Boundary, as acoustics beginning boundary (i.e. pressure fluctuation amount is 0)；
4) according to experiment main road flow and the frequency range that need to be studied, rotating disc type fluctuation pressure driver, turret apertures are selected
Diameter is 6mm, and the pressure of driving source pipeline is 4.5MPa, builds the waterpower excitation system for generating medium, high frequency fluctuation pressure signal, two
The aperture of a throttle is 7mm, a diameter of 10mm of waterpower excitation system pressure duct, is arranged in waterpower excitation system outlet end
Symmetrical fluctuation pressure Sensor and steady state pressure Sensor；
5) outlet of waterpower excitation system is connected in the oxidant head cavity of combustion chamber or in main line, ensures pulsating pressure
Only possible flat, straight, short of pipeline between power driver and oxidant head cavity；
6) accumulator that 300L volumes are installed on testing stand pipeline ensures that accumulator includes 1/5~1/3 total appearance in experiment
Long-pending air cushion；
7) testing stand main road leads to liquid, and flow is incrementally increased to the 25kg/s flow rate working conditions of experiment setting, remained unchanged；
8) waterpower excitation system leads to liquid, the electrical power of rotating disc type fluctuation pressure driver, by waterpower excitation system stable state
Pressure mean value gradually increases to setting value 4.5MPa, and the motor of fluctuation pressure driver maintains initial extremely low running speed；
9) it is programmed by PID, the motor control voltage of fluctuation pressure driver is incrementally increased, so that pulsating pressure in 300s
Power driving frequency at the uniform velocity increases to 1200Hz from 0Hz, then is at the uniform velocity reduced to 0Hz from 1200Hz in 300s, completes one and sweeps
Frequency Energizing cycle completes the frequency run of liquid conveying system after the right h type engine h oxygen pump.
Claims (5)
1. a kind of big flow liquid conveying system frequency run system, it is characterised in that：It is defeated including testing stand (14), liquid
Send system (1), waterpower excitation system (2), accumulator (4) and orifice union (3)；
The liquid conveying system (1) includes sequentially connected main pipe (6), oxidant main valve (7), combustion chamber oxidant head cavity
(8) and ejector filler (9)；
The waterpower excitation system (2) includes first throttle circle (5) and the second throttle being connected on driving source pipeline (10)
(11), bypass line (13) is provided between the first throttle circle (5) and the second throttle (11), rotating disc type fluctuation pressure swashs
Device (12) is encouraged to be arranged on bypass line (13)；
The testing stand (14) and main pipe (6) are connected by testing stand main line (15), the accumulator (4) and orifice union
(3) it is arranged on testing stand main line (15)；
Waterpower excitation system (2) outlet is connected in the combustion chamber oxidant head cavity (8) of liquid conveying system (1).
2. big flow liquid conveying system frequency run system according to claim 1, it is characterised in that：The liquid
Body conveying system (1) arranges fluctuation pressure measuring point along journey.
3. big flow liquid conveying system frequency run system according to claim 2, it is characterised in that：The liquid
Body conveying system (1) is at least 4 along the quantity of journey fluctuation pressure measuring point.
4. big flow liquid conveying system frequency run system according to claim 3, it is characterised in that：The liquid
Body conveying system (1) along journey fluctuation pressure measuring point quantity at 10 or more.
5. big flow liquid conveying system frequency run system according to any one of claims 1 to 4, feature exist
In：It is characterized in that：The branch line diameter for connecting accumulator is identical as the caliber of testing stand main line (15).
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108087155A (en) * | 2017-12-19 | 2018-05-29 | 西安航天动力研究所 | A kind of big flow liquid conveying system frequency run system and method |
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- 2017-12-19 CN CN201721781163.3U patent/CN207701245U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108087155A (en) * | 2017-12-19 | 2018-05-29 | 西安航天动力研究所 | A kind of big flow liquid conveying system frequency run system and method |
| CN108087155B (en) * | 2017-12-19 | 2024-02-09 | 西安航天动力研究所 | Test method of frequency characteristic test system of high-flow liquid conveying system |
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