CN100523761C - Dynamic pressure probe and method for measuring high temp jet dynamic pressure by the probe - Google Patents
Dynamic pressure probe and method for measuring high temp jet dynamic pressure by the probe Download PDFInfo
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- CN100523761C CN100523761C CNB2006100907673A CN200610090767A CN100523761C CN 100523761 C CN100523761 C CN 100523761C CN B2006100907673 A CNB2006100907673 A CN B2006100907673A CN 200610090767 A CN200610090767 A CN 200610090767A CN 100523761 C CN100523761 C CN 100523761C
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Abstract
The invention discloses a dynamic pressure measuring probe and a method for measuring high temperature jet dynamic pressure by this probe. And it comprises a water cooled conical pressure probe and pressure sensor, where the water cooled conical pressure probe comprises outer tube whose head is made with sampling hole and whose center is provided with water-air isolating tube, the interacvity of the water-air isolating tube is formed with an airflow channel and a cooling water channel is formed between the water-air isolating tube and outer tube, the tail end of the outer tube is connected with the pressure sensor, the sensing surface of the pressure sensor corresponds to the airflow channel, and the pressure sensor is connected in turn with amplifier and signal collection system by signal lines. And the invention reduces inlet water pressure requirements and reduces measuring cost, and can conveniently and quickly obtain dynamic pressure distribution on jet cross section, largely reducing measuring time.
Description
Technical field
The present invention relates to a kind of dynamic pressure measurement probe and with the method for this probe measurement high temp jet dynamic.
Background technology
The hot plasma jet is as the high energy beam current with high temperature, high enthalpy characteristic, all have a wide range of applications at Aero-Space, machining, metallurgy, chemical industry and bioengineering field, parameters such as the temperature of hot plasma jet and speed are the important parameters that characterizes its flow characteristics.According to jet temperature that measures and dynamic pressure data derivation effluxvelocity is a kind of speed-measuring method commonly used.The plasma jet temperature is generally at 3000-15000K, and it generally is to cooperate by water-cooled pitot tube and U type pipe (or microbarograph) to carry out that conventional hot plasma jet dynamic is measured, and belongs to contact measurement method.Promptly the pitot tube fixed placement in jet position to be measured, the pitot tube head has a thieff hatch over against jet incoming flow position, has the gas passage to link to each other with U type pipe behind the thieff hatch, can obtain the dynamic pressure of this position of jet by the variation of U type pipe water column.Because the jet temperature is very high, therefore when measuring jet dynamic, pitot tube is water-cooled well.General pitot tube is made integrative-structure to pipe shaft down to pitot tube bearing integral body from the head, and the pitot tube head is circular, and chilled water must flow through near the pitot tube head, and can not form the dead band of current at head, otherwise pitot tube will be burnt out; Because the pitot tube pressure measurement belongs to contact measurement method, can produce disturbance to tested air-flow.In order to reduce disturbance to tested air-flow, should reduce the size of pitot tube, so the passage of Inlet and outlet water is very little as far as possible, need to adopt high-pressure hydraulic pump to entering the chilled water supercharging of pitot tube, improve discharge with this and guarantee cooling effect; Though reduce the pitot tube size is the most effectual way that reduces disturbance, yet special process technology will make the price surge of pitot tube, and general demander can't be born; The maximum temperature of plasma jet often surpasses 10,000 degree, particularly when having added the high gas of thermal conductivities such as hydrogen in the Gas Jet, the use of pitot tube needs SC, otherwise the pitot tube head may be caused pitot tube integral body to be scrapped by scaling loss, and this has also limited the trial to the actual usable range of pitot tube.Owing to the natural period of oscillation very long (second-time) of U type pipe, it can not respond the jet dynamic signal fast simultaneously.Therefore in order to measure the accurate signal of jet dynamic, pitot tube needs the long period to be placed in the high temp jet, and this has also quickened the ablation of pitot tube head to a certain extent, thereby has shortened the serviceable life of pitot tube.How accurate and effective can be saved again and is operable to that local to measure jet dynamic be that people have problem to be solved always.
Summary of the invention
The objective of the invention is to overcome the defective of above-mentioned existing pressure testing method, provide that a kind of cost is low, efficient is high, dynamic pressure measurement probe that can quick and convenient measurement high temp jet dynamic and with the method for this probe measurement high temp jet dynamic.
For achieving the above object, technical solution of the present invention is:
A kind of method of using dynamic pressure measurement probe measurement high temp jet dynamic, at first adjust the position between plasma generator and the dynamic pressure measurement probe, the thieff hatch of assurance dynamic pressure measurement probe and plasma generator axis are on same straight line, mark probe present position this moment moves on to the jet outside to probe by gearing then; After plasma generator produces plasma jet, the dynamic pressure measurement probe is moved on to fast the position that mixes up in advance, and do suitable fine setting, when the signal that arrives with sensor sensing is maximum for well, according to the conversion relation between described pressure transducer response signal and the actual pressure, promptly obtain jet-core region dynamic pressure fluctuation signal.
Further, by making dynamic pressure measurement probe edge perpendicular to the quick inswept jet area of the direction of jet axis, pressure-measuring probe is moved on to the position that mixes up in advance fast, and pressure transducer is understood the dynamic pressure signal of real-time response plasma jet in this process, obtains the radial distribution of jet dynamic thus.
The structure of the dynamic pressure measurement probe that uses in the said method is, comprise water-cooled taper pressure probe and pressure transducer, this water-cooled taper pressure probe comprises outer tube, outer tube head has thieff hatch, the center of described outer tube is provided with the aqueous vapor isolated tube, form gas channel at this aqueous vapor isolated tube inner chamber, between aqueous vapor isolated tube and outer tube, form cooling-water duct, be connected with pressure transducer at described outer tube end, the sensitive surface of this pressure transducer is corresponding with described gas channel, and this pressure transducer connects amplifier, signal acquiring system successively by signal wire.
Further, described outer tube comprises outer tube body and the conical head that removably connects, and this conical head is provided with thieff hatch.
Further, the diameter of described thieff hatch is less than 1mm.
Further, the ratio of the length of described gas channel and diameter is 20-60.
Further, described gas channel end is provided with the flared tube of Diameter Gradual Change.
Further, the expansion half-angle of described flared tube is less than or equal to 50 °.
After adopting device and method of the present invention, because working pressure sensor, reduced the residence time of dynamic pressure measurement probe in high temp jet, can reduce requirement to the cooling water feeding pressure, reduce and measure cost, because of the dynamic pressure measurement probe has the very high speed of response, the dynamic pressure of jet xsect can be obtained quickly and easily again, Measuring Time can be reduced significantly.The head of probe is detachable and be designed to taper, and conical head can reduce in measuring process the disturbance to jet, the accuracy that improves measurement result; Conical head is detachable, makes this dynamic pressure measurement probe select different center probe bore size according to measurement requirement, and can change the conical head cone angle to inquire into its disturbing influence to jet; In addition, because the jet extreme temperatures, end of probe is the part of ablating easily, and this detachable design can avoid probe integral body to scrap because of the probe scaling loss, is more convenient for the experiment measuring of exploration.And be provided with the Inlet and outlet water isolated tube between the aqueous vapor isolated tube of dynamic pressure measurement probe of the present invention and the outer tube, form the chilled water intake tunnel between Inlet and outlet water isolated tube and the aqueous vapor isolated tube, form the chilled water exhalant canal between Inlet and outlet water isolated tube and the outer tube, guarantee the cooling effect of chilled water, improve the serviceable life of probe; The thieff hatch diameter of this device is less than 1mm, thereby guarantee that measurement result has higher spatial resolution, the length of gas channel and the ratio of diameter are 20-60, the gas channel end is provided with the flared tube of Diameter Gradual Change, the expansion half-angle of flared tube is less than or equal to 50 °, reduced the dynamic pressure loss that the abrupt change of cross-section causes, made measurement result truer.
Description of drawings
Fig. 1 is the structural representation of dynamic pressure measurement probe;
Fig. 2 schemes over time for jet dynamic;
Fig. 3 is the radial distribution measurement result figure of jet dynamic.
Embodiment:
High temp jet dynamic of the present invention the time outage response measurement method required dynamic pressure measurement probe as shown in Figure 1, comprise water-cooled taper pressure probe and pressure transducer, this water-cooled taper pressure probe 1 comprises outer tube 11, outer tube 11 comprises outer tube body 111 and the conical head 112 that removably connects, these conical head 112 front ends have thieff hatch 113, the center of this outer tube 11 connects aqueous vapor isolated tube 12, in aqueous vapor isolated tube 12, be formed centrally gas channel 14, between aqueous vapor isolated tube 12 and outer tube 11, be provided with Inlet and outlet water isolated tube 13, form the chilled water intake tunnel between Inlet and outlet water isolated tube 13 and the aqueous vapor isolated tube 12, intake tunnel is provided with water inlet, form the chilled water exhalant canal between Inlet and outlet water isolated tube 13 and the outer tube 11, this exhalant canal is provided with water delivering orifice; Be provided with probe base 15 at described outer tube 11 ends, be fixed with pressure transducer 16 on this probe base 15, the sensitive surface 161 of this pressure transducer 16 is corresponding with gas channel 14, and is provided with packoff between pressure transducer 16 and the probe base 15; This pressure transducer 16 connects amplifier 18, signal acquiring system 19 successively by signal wire 17.
As shown in Figure 1, during use, high temperature gas flow A acts on the sensitive surface 161 of pressure transducer 16 by pressure-measuring probe head thieff hatch 113 and gas channel 14, pressure transducer 16 is converted to millivolt voltage signal of level to the pressure signal of sensing, and is gathered by signal acquiring system 19 by signal wire 17 and amplifier 18.By demarcating the good actual pressure and the relation curve of sensor output voltage signal in advance, can obtain actual dynamic pressure data.Pressure-measuring probe designs for water-cooled, and chilled water enters the water-cooled path of probe by water inlet, and until end of probe, Inlet and outlet water isolated tube 13 is divided into cooling water path in the water path and goes out water passage, and chilled water flows out pressure-measuring probe through water delivering orifice.Aqueous vapor isolated tube 12 separates gas channel 14 and water-cooled path, and outer tube 11 separates the high temperature gas flow of probe outside.
For guaranteeing that measurement result has higher spatial resolution, the diameter of described thieff hatch 113 need be done little as far as possible, and the diameter of thieff hatch 113 is less than 1mm in the present embodiment.The design of gas channel 14 need be considered factors such as thieff hatch aperture, passage length, channel cross-section version, be that gas channel 14 and thieff hatch 113 can not be that the aperture differs too many abrupt change of cross-section design, because of when the pipeline section sudden enlargement, fluid can produce certain flow losses (being mainly eddy current loss), it is shock resistance, because shock resistance effect, jet will have the dynamic pressure loss, thereby make the dynamic pressure distorted signals that measures; Square being directly proportional of dynamic pressure loss coefficient and big or small area of section difference and heavy in section ratio, it is many more that both areas differ, and the dynamic pressure loss coefficient is big more; Gas channel 14 need have suitable length, to guarantee the air-flow in the abundant cooling channel, makes response signal depart from the possibility of True Data thereby reduce pressure transducer 16 because of warm the floating of the generation of being heated; When guaranteeing the air-flow cooling, need the volume of control gas channel 14, be beneficial to the response of probe; Because being delivered to sensor sensing face 161, the dynamic pressure information of measurement point needs the experience regular hour, volume is big more, time is long more, thereby influence the response of probe, if that is: measured signal is a high-frequency pulse signal, the excessive dither that is unfavorable for the probe response measured signal of gas channel volume, thus the authenticity of measurement result influenced; In the present embodiment, the length of gas channel 14 and the ratio range of diameter are between 20-60; The end of gas channel 14 is consolidated with pressure transducer 16, because gas channel 14 is bigger with the diameter difference of pressure transducer 16 sensitive surface 161, in this patent, gas channel 14 ends are provided with the flared tube 20 of Diameter Gradual Change, reduce the dynamic pressure loss that the abrupt change of cross-section causes as far as possible, the expansion half-angle of flared tube 20 should be not more than 50 °, to obtain real dynamic pressure data as far as possible.
For adjusting the position between pressure-measuring probe head thieff hatch 113 and the jet measurement point easily, described pressure-measuring probe is fixed in can front and back, on the level, the gearing that moves up and down, measuring jet dynamic in time during variation characteristic, pass through gearing, rapidly the dynamic pressure measurement probe is moved to the jet measurement point, because the dynamic pressure measurement probe has the very high speed of response, therefore can in the extremely short time, obtain the time dependent data of jet dynamic.And for the jet dynamic distributed data, when probe by gearing along perpendicular to the quick inswept jet area of the direction of jet axis the time, the dynamic pressure signal that pressure transducer 16 output in real time responds, according to the conversion relation between pressure transducer response signal and the actual pressure signal, Measuring Time and pressure probe translational speed multiply each other simultaneously, can obtain jet dynamic along jet distribution radially.By change probe along Jet Axis to the position, can obtain the jet dynamic radial distribution of different axial locations apace.Because working pressure sensor in the measuring process, it has the very high speed of response, can respond the dynamic pressure signal fast, therefore can adopt the method for pressure-measuring probe along the quick inswept jet area of direction of vertical fluid axis, obtains the dynamic pressure of jet.
Pressure-measuring probe thieff hatch 113 diameters of choosing in the present embodiment are 0.6mm, and gas channel 14 diameters are 1.2mm, and length is 50mm.Pressure transducer 16 has the response frequency of 40kHz, is output as the mV signal, and maximum range is 60kPa.Pressure transducer 16 is by the strain amplifier power supply, and by the oscillograph collection, final data is by Computer Storage after strain amplifier amplifies 100 times for Shu Chu mV signal simultaneously.Chilled water is provided by the cooling circulating water machine, and the cooling water feeding pressure is adjusted to 4 kg/cm.
When Fig. 2 is in different flow state for jet the jet-core region dynamic pressure over time, wherein the last figure of Fig. 2 is the dynamic pressure measurement result that jet is in the Laminar Flow state, figure below is the dynamic pressure measurement result that jet is in the turbulent flow state.At first to adjust the height and the levelness of conical nose thieff hatch 113 before the measurement, make its axis and plasma generator axis point-blank, write down this position, by gearing, pressure-measuring probe be removed generator exports then; Striking subsequently, generator produces plasma jet, after adjusting jet parameters, fast pressure-measuring probe is moved on to the position, jet-core region by gearing, just jet-core region dynamic pressure signal that can gaging pressure sensor real-time response, according to pressure transducer response signal of demarcating in advance and the conversion relation between the actual pressure signal, can obtain jet-core region dynamic pressure fluctuation signal, Measuring Time has only a millisecond magnitude.See having dither in the dynamic pressure signal when jet is in turbulent flow from figure, and ripple frequency is consistent with the arc voltage ripple frequency that produces jet, promptly pressure probe can respond the dynamic pressure signal that high frequency changes.Fig. 3 is the radial distribution result apart from the plasma jet dynamic pressure of generator exports 5mm place that the dynamic pressure measurement device of application drawing 1 obtains.The movement velocity of gearing is 111mm/s in the measurement, and the about 5mm of demonstration jet diameter among the figure, the residence time of pressure-measuring probe in the jet 43ms that only has an appointment is described, just can obtain along jet dynamic pressure radially, Duan time so, be to measure with the mode of conventional water-cooled pitot tube and the combination of U type pipe can not accomplish that this has further proved the high efficiency of measurement jet dynamic method provided by the invention when jet dynamic distributes.
Claims (8)
1, a kind of method of using dynamic pressure measurement probe measurement high temp jet dynamic, it is characterized in that, at first adjust the position between plasma generator and the dynamic pressure measurement probe, the thieff hatch of assurance dynamic pressure measurement probe and plasma generator axis are on same straight line, mark probe present position this moment moves on to the jet outside to pressure-measuring probe by gearing then; After plasma generator produces plasma jet, the dynamic pressure measurement probe is moved on to fast the position that mixes up in advance, and do suitable fine setting, when the signal that arrives with sensor sensing is maximum for well, according to the conversion relation between described pressure transducer response signal and the actual pressure, promptly obtain jet-core region dynamic pressure fluctuation signal.
2, the method for claim 1, it is characterized in that, by making dynamic pressure measurement probe edge perpendicular to the quick inswept jet area of the direction of jet axis, pressure-measuring probe is moved on to fast the position that mixes up in advance, pressure transducer is understood the dynamic pressure signal of real-time response plasma jet in this process, obtains the radial distribution of jet dynamic thus.
3, method as claimed in claim 1 or 2, wherein, the structure of described dynamic pressure measurement probe is, comprise water-cooled taper pressure probe and pressure transducer, this water-cooled taper pressure probe comprises outer tube, outer tube head has thieff hatch, the center of described outer tube is provided with the aqueous vapor isolated tube, form gas channel at this aqueous vapor isolated tube inner chamber, between aqueous vapor isolated tube and outer tube, form cooling-water duct, be connected with pressure transducer at described outer tube end, the sensitive surface of this pressure transducer is corresponding with described gas channel, and this pressure transducer connects amplifier successively by signal wire, signal acquiring system.
4, method as claimed in claim 3 is characterized in that, the outer tube of described dynamic pressure measurement probe comprises outer tube body and the conical head that removably connects, and this conical head is provided with thieff hatch.
5, method as claimed in claim 4 is characterized in that, the diameter of the thieff hatch of described dynamic pressure measurement probe is less than 1mm.
6, method as claimed in claim 3 is characterized in that, the length of the gas channel of described dynamic pressure measurement probe and the ratio of diameter are 20-60.
7, method as claimed in claim 6 is characterized in that, the gas channel end of described dynamic pressure measurement probe is provided with the flared tube of Diameter Gradual Change.
8, method as claimed in claim 7 is characterized in that, the expansion half-angle of the flared tube of described dynamic pressure measurement probe is less than or equal to 50 °.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100907673A CN100523761C (en) | 2006-06-30 | 2006-06-30 | Dynamic pressure probe and method for measuring high temp jet dynamic pressure by the probe |
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| CNB2006100907673A CN100523761C (en) | 2006-06-30 | 2006-06-30 | Dynamic pressure probe and method for measuring high temp jet dynamic pressure by the probe |
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| CN1869623A CN1869623A (en) | 2006-11-29 |
| CN100523761C true CN100523761C (en) | 2009-08-05 |
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| CN102455231B (en) * | 2010-10-25 | 2013-09-11 | 北京卫星环境工程研究所 | Testing system for pressure and temperature of supersonic engine plume field |
| CN106706204B (en) * | 2017-02-20 | 2022-06-21 | 华能国际电力股份有限公司 | Pressure sensor cooling device suitable for high temperature environment test |
| CN107131999A (en) * | 2017-04-18 | 2017-09-05 | 北京航空航天大学 | A kind of high-temperature water cooling stable state pressure-measuring probe |
| CN107063560A (en) * | 2017-04-24 | 2017-08-18 | 北京航空航天大学 | A kind of high-temperature water cooling dynamic pressure measurement probe |
| CN107036758A (en) * | 2017-05-05 | 2017-08-11 | 北京航空航天大学 | A kind of air cooling high temperature dynamic pressure probe |
| CN107167283A (en) * | 2017-05-05 | 2017-09-15 | 北京航空航天大学 | A kind of air cooling High Temperature and Stable State pressure probe |
| CN108871664B (en) * | 2018-06-26 | 2024-01-19 | 成都英鑫光电科技有限公司 | Air pressure measuring device and system |
| CN109540372B (en) * | 2018-11-12 | 2021-02-09 | 中国飞行试验研究院 | Novel multi-mode pressure measurement probe |
| CN112630466B (en) * | 2020-12-03 | 2023-10-31 | 深圳市蜉飞科技有限公司 | Airspeed meter is with atmospheric pressure collection structure and fixed wing unmanned aerial vehicle |
| CN112649172B (en) * | 2020-12-21 | 2022-12-16 | 中国航天空气动力技术研究院 | Static pressure probe and high-enthalpy shock tunnel static pressure measurement method |
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| US4783994A (en) * | 1988-01-13 | 1988-11-15 | The Administrator Of The National Aeronautics And Space Administration | Pressure measuring probe |
| US5076103A (en) * | 1990-08-31 | 1991-12-31 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Water cooled static pressure probe |
| CN2738207Y (en) * | 2004-10-22 | 2005-11-02 | 中国科学院力学研究所 | Disturbance reducing enthalpy probe |
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2006
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4783994A (en) * | 1988-01-13 | 1988-11-15 | The Administrator Of The National Aeronautics And Space Administration | Pressure measuring probe |
| US5076103A (en) * | 1990-08-31 | 1991-12-31 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Water cooled static pressure probe |
| CN2738207Y (en) * | 2004-10-22 | 2005-11-02 | 中国科学院力学研究所 | Disturbance reducing enthalpy probe |
Non-Patent Citations (2)
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| Heat and mass transfer during in-flight nitridationof molybdenum disilicide powder in an induction plasmareactor. Gervais Soucy et. al.Materials Science and Engineering. 2001 * |
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