CN103267681A - Method and device for measuring oil volume elastic modulus - Google Patents

Method and device for measuring oil volume elastic modulus Download PDF

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Publication number
CN103267681A
CN103267681A CN201310148011XA CN201310148011A CN103267681A CN 103267681 A CN103267681 A CN 103267681A CN 201310148011X A CN201310148011X A CN 201310148011XA CN 201310148011 A CN201310148011 A CN 201310148011A CN 103267681 A CN103267681 A CN 103267681A
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CN
China
Prior art keywords
fluid
bulk modulus
oil
measurement
pressurized reservoir
Prior art date
Application number
CN201310148011XA
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Chinese (zh)
Inventor
乌建中
范昌龙
誾耀保
乐韵斐
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同济大学
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Priority to CN201310148011XA priority Critical patent/CN103267681A/en
Publication of CN103267681A publication Critical patent/CN103267681A/en

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Abstract

The invention discloses a method for measuring an oil volume elastic modulus. A measure result of the method is more accurate. Based on the definition of a liquid volume elastic modulus, the oil compression amount is subjected to volume compensation in the measure test. The invention also discloses a device for measuring an oil volume elastic modulus. The device comprises a pressurization device, an oil pipe transition block and a measure device. The measure device comprises a water tank, a compression oil tank, a pressurization oil tank, a graduated glass tube and a piston rod ruler. The method comprises the steps that the pressurization device carries out pressurization on the compression oil tank by the pressurization oil tank; the change of the liquid level in the graduated glass tube is read so that the micro volume deformation of the compression oil tank is obtained; the oil compression amount is subjected to volume compensation; and the volume elastic modulus of the oil in the compression oil tank is calculated accurately. The device is convenient for operation and can be realized easily. The method has high efficiency and can produce an accurate result.

Description

A kind of fluid bulk modulus measuring method and device
Technical field
The invention belongs to hydraulic transmission technology field, relate to electrohydraudic servomechanism, especially fluid bulk modulus measuring method and device.
Background technology
Elastic modulus is an important physical parameter of fluid, characterize the rigidity of fluid, accurately whether its value, directly influence natural frequency and the damping ratio of Hydraulic Elements and system, thereby affect the correctness of precision, stability, dynamic quality and result of study to systematic analysis, therefore, be that the research of elastic modulus is important problem in the hydraulic technique field to the fluid compressibility, method and device that a kind of intuitively easy, pinpoint accuracy of development and Design is measured the fluid bulk modulus have outstanding practical value.
Summary of the invention
The object of the present invention is to provide a kind of fluid bulk modulus measuring method and device.
The fluid bulk modulus is defined as:
K = V 0 ΔP ΔV
In the formula:
K-fluid bulk modulus;
V 0The volume of-fluid original state;
△ P-fluid pressure change amount;
△ V-fluid stereomutation the amount corresponding with △ P.
By piston the fuel tank inner fluid is exerted pressure, fluid records the decrement △ V of fluid this moment with compressed, and this △ V not only is merely the decrement △ V of fluid Fluid, and comprise that the fluid container is the distortion △ V of fuel tank Fuel tank, that is: △ V=△ V Fluid+ △ V Fuel tank, therefore need be negative to the decrement △ V(of fluid) and compensation, the K value is revised,
Be K ':
V wherein 0, △ P, △ V can directly record, if can record △ V Fuel tank, then K just can try to achieve.
Generally speaking, fluid under pressure, the deformation ratio of fuel tank is more small, is difficult to accurately to obtain △ V with theoretical Calculation Method Fuel tank
For measuring △ V Fuel tank, solution of the present invention is: adopt drainage to survey △ V Fuel tank, can obtain accurate fluid bulk modulus K ' value by further calculating.
Drainage is that the fluid fuel tank is immersed in the water (or other liquid), measures fuel tank volume change △ V indirectly Fuel tankMethod.Specifically pressurize the pistons, fluid is compressed, and the fuel tank distortion is expanded, and water surface elevation changes in the container, can draw the subtle change △ V of fuel tank volume Fuel tank
Drainage is measured:
(1) be volume V 0Fluid to be measured put into fuel tank;
(2) give the suitable pressure P of piston 1, record fuel tank fluid this moment volume V 1With container glass pipe liquid level H 1
(3) increase piston pressure to P 2, record fuel tank fluid this moment volume V 2With container glass pipe liquid level H 2
Then:
△P=P 2-P 1
△V=V 1-V 2=△H 1·S 1
(S wherein 1Be piston effective area),
△ V Fuel tank=(H 2-H 1) S 2=△ HS 2
(S wherein 2Be circle useful area in the glass tube),
According to formula
Can release:
A kind of fluid bulk modulus measurement mechanism that can be used for realizing said method, comprise: pressue device, oil pipe transition block and measurement mechanism, also comprise pressure transducer and display, it is arranged on the oil pipe transition block, by the activity draw bail, for example be threaded; Described pressue device, oil pipe transition block and measurement mechanism are linked in sequence by the fluid flexible pipe.
Further: described pressue device is hydraulic hand-pump, and the pump head of described hydraulic hand-pump is provided with tensimeter.
Described oil pipe transition block is the hollow and thin-walled piece, is provided with four screws up and down, and last hole is pressure sensor interface, and following hole is unloading port, about mouthful be the fluid hose connection, be connected to described pressue device and measurement mechanism respectively.
Described measurement mechanism is respectively water tank, pressure oil tank and pressurized reservoir three-decker from outside to inside; Preferably: water tank, pressure oil tank and pressurized reservoir are the cylinder thin-walled box, described three the casees coaxial, the end flushes, and is fixed on the ring flange; Further preferred: described pressurized reservoir is two rank cylinder hollow tubes, and the pressurized reservoir small diameter cylinders is stretched out ring flange by the ring flange hollow space, is furnished with the piston identical with the pressurized reservoir internal diameter in the pressurized reservoir.
Described pressurized reservoir small diameter cylinders side offers a screw and is used for connecting the pressurization oil pipe.
Be respectively equipped with suspension ring hole, scale glass tube fixed orifice, piston rod scale holder and oil hole on the described ring flange from outside to inside.
Described scale glass tube is to be threaded with flange face, and stands on the described ring flange.
Described piston rod scale is welded on the piston rod scale holder perpendicular to flange surface.
Described water tank bottom is provided with unloading port.
Owing to adopted such scheme, advantage of the present invention is: 1. based on the definition of liquid volume elastic modulus, in measuring test the fluid decrement is carried out volume compensation, make the result more accurate reliable.2. because the totally-enclosed design of pressure oil tank of measurement mechanism, can to the fluid of different temperatures and different air contents under different pressures, measure 3. install simple and reliable, easy and simple to handle.4. shortening measuring period and measurement cost reduce greatly.
Description of drawings
Fig. 1 is the vertical view of fluid bulk modulus measurement mechanism embodiment of the present invention.
Fig. 2 is that fluid bulk modulus shown in Figure 1 is measured measurement mechanism longitudinal profile structural map.
Fig. 3 is fluid bulk modulus measurement mechanism connection diagram of the present invention.
Embodiment
The present invention is described further below in conjunction with the accompanying drawing illustrated embodiment.
Fig. 1 and Fig. 2 are fluid bulk modulus measurement mechanism structure of the present invention.As shown in the figure, comprise: water tank 203, pressure oil tank 201 and pressurized reservoir 212 are welded on the ring flange 213 from outside to inside successively, ring flange 213 ring-type hollows wherein, pressurized reservoir 212 is two rank cylinder hollow tubes, and pressurized reservoir 212 small diameter cylinders are stretched out ring flange by ring flange 213 hollow spaces; Piston rod 210 closely contacts with pressurized reservoir 212 inwalls by O-ring seal; Be respectively 2 of suspension ring hole 102(symmetries from outside to inside on the ring flange 213), scale glass tube fixed orifice 104, piston rod scale holder 101 and oil hole 103(evenly distribute 4), wherein, scale glass tube fixed orifice 104 and oil hole 103 are to connect ring flange 213; Scale glass tube 205 is fixed in the scale glass pore 104 perpendicular to ring flange by being threaded, piston rod scale 207 is welded on the piston rod scale holder 101 perpendicular to flange surface, pressurization oil pipe 209 is parallel to flange surface and is vertically fixed on the pressurized reservoir 212 small diameter cylinders sides, and it is connected to and is threaded; Pressure transducer 211 is vertically fixed on the flange surface by one of them oil hole, and it is connected to and is threaded; Water tank wall is provided with Unloading Device 215.
Pressure oil tank 201, the fluid of elastic modulus to be measured is equipped with in the inside, the purpose of this covering device is the microdeformation that will measure this fuel tank, the effect of piston end cap 202 is strokes of limited piston bar 210, water (or other liquid) is filled in water tank 203 the insides, water in the water tank 203 and scale glass tube 205 communicate, during measurement, change to represent the volume change of pressure oil tank 201 with water surface elevation in the scale glass tube 205, fluid to be measured is by oil hole 103, injection pressure oil tank 201, piston rod scale 207 is parallel with piston rod 210, in order to demarcate the height of piston rod bidding quotation 208.In the test, refuel in pressurized reservoir 212 by pressurization oil pipe 209, pressurized reservoir 212 pressure increase, promote piston rod and move down the fluid to be measured that compresses in the pressure oil tank 201, and then oil liquid pressure to be measured increases (its pressure and pressurized reservoir internal pressure ratio are fixed) in the pressure oil tank 201, make the pressure oil tank volume increase, that is to say the volume that we need measure.Pressure transducer 211 is fixed on the flange face, and communicates with pressure oil tank 201, measures the real-time pressure of fluid to be measured.
Fig. 3 is the device connection diagram, comprising: pressue device 301, select hydraulic hand-pump for use.Pressure gauge outfit 302, unloading port 304, they all are fixed on the oil pipe transition block 303, and pressue device 301, oil pipe transition block 303 and measurement mechanism 306 are linked in sequence by fluid flexible pipe 305.
Measure in the test, treat each parts of system install connect finish after, in pressure oil tank, add fluid to be measured, the record institute liquid that refuels amasss.Again from the scale glass tube toward the slow water filling of water tank, a little until the liquid level scale glass tube of emerging.Then with slowly pressurization of pressue device (hydraulic hand-pump) (this moment, piston descended, and the glass tube liquid level raises, and it is big that pressure sensor readings becomes), record piston rod scale, glass tube liquid level scale and pressure sensor readings one time; Slowly pressurize with hydraulic hand-pump again, increased preset value until pressure, record piston rod scale, glass tube liquid level scale and pressure sensor readings one time.So repeatedly till pressure sensor readings reaches the required maximum pressure value of test.Bring all data of record into just can calculate the fluid bulk modulus in the correction formula exact value.
Fluid bulk modulus measurement mechanism of the present invention carries out volume compensation to the fluid decrement based on the definition of liquid volume elastic modulus in measuring test, make the result more accurate reliable.The totally-enclosed design of the pressure oil tank of measurement mechanism can be measured under different pressures the fluid of different temperatures and different air contents, and installs simple and reliablely, easy and simple to handle, shortens measuring period and measures cost and reduce greatly.By obtaining the bulk modulus of fluid, can calculate frequency characteristic and the stiffness characteristics of electrohydraudic servomechanism theoretically, thereby static state, dynamic perfromance to electrohydraudic servomechanism are carried out theory and experimental evaluation, and the frequency characteristic of electrohydraudic servomechanism under the following operating mode are predicted with fault analysis basic data is provided.
The above-mentioned description to embodiment is can understand and apply the invention for ease of those skilled in the art.The person skilled in the art obviously can easily make various modifications to these embodiment, and needn't pass through performing creative labour being applied in the General Principle of this explanation among other embodiment.Therefore, the invention is not restricted to the embodiment here, those skilled in the art are according to announcement of the present invention, and not breaking away from the improvement that category of the present invention makes and revise all should be within protection scope of the present invention.

Claims (10)

1. the method measured of a fluid bulk modulus, it is characterized in that: the fluid container that fluid will be housed is immersed in the liquid, and by the pressurization of the fluid in the oil dropping apparatus, fluid is compressed, the fuel tank distortion is expanded, according to the change amount Δ V of the fuel-displaced liquid container volume of water surface elevation change calculations in the container Fuel tank, calculate fluid bulk modulus K ' according to following formula afterwards:
Wherein: V 0The volume of-fluid original state;
Δ P-fluid pressure change amount;
Δ V-fluid stereomutation the amount corresponding with Δ P.
2. fluid bulk modulus measurement mechanism that can be used for realizing the described method of claim 1, comprise: pressue device, oil pipe transition block and measurement mechanism, it is characterized in that: also comprise pressure transducer and display, it is arranged on the oil pipe transition block, connects by the activity draw bail; Described pressue device, oil pipe transition block and measurement mechanism are linked in sequence by the fluid flexible pipe.
3. fluid bulk modulus measurement mechanism according to claim 2, it is characterized in that: described pressue device is hydraulic hand-pump, and the pump head of described hydraulic hand-pump is provided with tensimeter.
4. fluid bulk modulus measurement mechanism according to claim 2, it is characterized in that: described oil pipe transition block is the hollow and thin-walled piece, be provided with four screws up and down, last hole is pressure sensor interface, following hole is unloading port, about mouthful be the fluid hose connection, be connected to described pressue device and measurement mechanism respectively.
5. fluid bulk modulus measurement mechanism according to claim 2, it is characterized in that: described measurement mechanism is respectively water tank, pressure oil tank and pressurized reservoir three-decker from outside to inside; Preferably: water tank, pressure oil tank and pressurized reservoir are the cylinder thin-walled box, described three the casees coaxial, the end flushes, and is fixed on the ring flange; Further preferred: described pressurized reservoir is two rank cylinder hollow tubes, and the pressurized reservoir small diameter cylinders is stretched out ring flange by the ring flange hollow space, is furnished with the piston identical with the pressurized reservoir internal diameter in the pressurized reservoir.
6. fluid bulk modulus measurement mechanism according to claim 5 is characterized in that: described pressurized reservoir small diameter cylinders side offers a screw and is used for connecting the pressurization oil pipe.
7. fluid bulk modulus measurement mechanism according to claim 5 is characterized in that: be respectively equipped with suspension ring hole, scale glass tube fixed orifice, piston rod scale holder and oil hole on the described ring flange from outside to inside.
8. fluid bulk modulus measurement mechanism according to claim 7, it is characterized in that: described scale glass tube is to be threaded with flange face, and stands on the described ring flange.
9. fluid bulk modulus measurement mechanism according to claim 7, it is characterized in that: described piston rod scale is welded on the piston rod scale holder perpendicular to flange surface.
10. fluid bulk modulus measurement mechanism according to claim 5, it is characterized in that: described water tank bottom is provided with unloading port.
CN201310148011XA 2013-04-25 2013-04-25 Method and device for measuring oil volume elastic modulus CN103267681A (en)

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Cited By (13)

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Publication number Priority date Publication date Assignee Title
CN103674703A (en) * 2013-12-12 2014-03-26 中国航空工业集团公司第六三一研究所 Test method and device for volume-elasticity modulus of liquid
CN103940731A (en) * 2014-04-18 2014-07-23 中国海洋石油总公司 Hydraulic oil elasticity modulus and thermal expansion coefficient measuring device
CN104142166A (en) * 2014-07-28 2014-11-12 北京机械设备研究所 Hydraulic closed oil tank oil scale corresponding to temperatures
CN104199995A (en) * 2014-07-15 2014-12-10 哈尔滨电机厂有限责任公司 Temperature compensation method for initial pressure of single-corrugation elastic oil tank
CN105004663A (en) * 2015-07-15 2015-10-28 中国计量科学研究院 Gas cylinder volume expansion accurate measurement device
CN103940731B (en) * 2014-04-18 2016-11-30 中国海洋石油总公司 Hydraulic oil elastic modelling quantity and thermal coefficient of expansion measurement apparatus
CN108760519A (en) * 2018-07-26 2018-11-06 中国人民解放军海军工程大学 A kind of fluid bulk modulus detection sensor and detection method
CN109596287A (en) * 2018-12-13 2019-04-09 无锡赛晶电力电容器有限公司 Capacitor oil compensates rational test method under a kind of High aititude
CN110160882A (en) * 2019-05-22 2019-08-23 燕山大学 A kind of gas-liquid two-phase fluid bulk modulus measuring device and method
CN110657871A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Gas weighing system
CN110657869A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Buoyancy compensation weighing device and buoyancy compensation method
CN110657870A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Gas weighing device
CN110857880A (en) * 2018-08-23 2020-03-03 中国石油天然气股份有限公司 Gas weighing system

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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103674703B (en) * 2013-12-12 2016-04-20 中国航空工业集团公司第六三一研究所 A kind of liquid volume elastic modulus method of testing and proving installation
CN103674703A (en) * 2013-12-12 2014-03-26 中国航空工业集团公司第六三一研究所 Test method and device for volume-elasticity modulus of liquid
CN103940731A (en) * 2014-04-18 2014-07-23 中国海洋石油总公司 Hydraulic oil elasticity modulus and thermal expansion coefficient measuring device
CN103940731B (en) * 2014-04-18 2016-11-30 中国海洋石油总公司 Hydraulic oil elastic modelling quantity and thermal coefficient of expansion measurement apparatus
CN104199995A (en) * 2014-07-15 2014-12-10 哈尔滨电机厂有限责任公司 Temperature compensation method for initial pressure of single-corrugation elastic oil tank
CN104199995B (en) * 2014-07-15 2017-07-11 哈尔滨电机厂有限责任公司 The temperature compensation of single-ripple elastic tank initial pressure
CN104142166B (en) * 2014-07-28 2017-06-16 北京机械设备研究所 A kind of hydraulic closed fuel tank oil scale corresponding with temperature
CN104142166A (en) * 2014-07-28 2014-11-12 北京机械设备研究所 Hydraulic closed oil tank oil scale corresponding to temperatures
CN105004663A (en) * 2015-07-15 2015-10-28 中国计量科学研究院 Gas cylinder volume expansion accurate measurement device
CN110657871A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Gas weighing system
CN110657869A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Buoyancy compensation weighing device and buoyancy compensation method
CN110657870A (en) * 2018-06-28 2020-01-07 中国石油天然气股份有限公司 Gas weighing device
CN108760519A (en) * 2018-07-26 2018-11-06 中国人民解放军海军工程大学 A kind of fluid bulk modulus detection sensor and detection method
CN110857880A (en) * 2018-08-23 2020-03-03 中国石油天然气股份有限公司 Gas weighing system
CN109596287A (en) * 2018-12-13 2019-04-09 无锡赛晶电力电容器有限公司 Capacitor oil compensates rational test method under a kind of High aititude
CN110160882A (en) * 2019-05-22 2019-08-23 燕山大学 A kind of gas-liquid two-phase fluid bulk modulus measuring device and method
CN110160882B (en) * 2019-05-22 2020-03-31 燕山大学 Device and method for measuring volume elastic modulus of gas-liquid two-phase fluid

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