CN209802916U - Hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device - Google Patents
Hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device Download PDFInfo
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- CN209802916U CN209802916U CN201920532756.9U CN201920532756U CN209802916U CN 209802916 U CN209802916 U CN 209802916U CN 201920532756 U CN201920532756 U CN 201920532756U CN 209802916 U CN209802916 U CN 209802916U
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Abstract
the utility model discloses a hydraulic pressure loading formula viscidity resistance coefficient and inertia resistance coefficient testing arrangement, the device is including experiment pipe and tuber pipe, the one end of experiment pipe passes through the ring flange with the other end of tuber pipe and is connected, the other end inner wall of experiment pipe slides and is equipped with the clamp plate, the experiment intussuseption between clamp plate and the ring flange is filled with the waste rock that has certain particle diameter, the clamp plate outside is connected with a push rod, the push rod is driven by a hydraulic press, install the differential gauge on the experiment pipe, two probe correspondences of differential gauge set up the both ends in waste rock filling area, the one end of tuber pipe is connected with fan and vacuum pump respectively, install anemometer and vacuum gauge on the tuber pipe respectively, anemometer surveys the wind speed in the tuber pipe, the vacuum of tuber pipe is surveyed to the vacuum gauge, the differential gauge. The utility model discloses be convenient for test viscous drag coefficient and inertial resistance coefficient under the different porosity in succession.
Description
Technical Field
the utility model relates to a coefficient of resistance test technical field especially relates to hydraulic pressure loading formula viscous drag coefficient and inertial resistance coefficient testing arrangement.
background
At present, most of coal mine roof management modes in China adopt a collapse method, and after a coal seam is mined, an overlying strata collapses to form a goaf. The goaf is essentially a porous medium formed by rocks and residual coal, and accords with the characteristics of an O-shaped ring, namely the goaf close to a roadway side, a cutting hole and a working surface has large gaps and high permeability; the middle part of the goaf is compacted, the gap is small, and the permeability is small.
Gas released by residual coal in the goaf enters an upper corner under the carrying of air leakage of a working face, and the gas concentration on the working face is easy to exceed the limit. The air leakage of the working face enters the goaf and leads to the separation of O2The coal is easy to be brought into the goaf to cause coal nature and cause fire in the goaf. Therefore, extensive scholars deeply research on the flowing rule of the gas in the goaf, wherein CFD simulation is an important research means. In numerical simulation, all studies consider the goaf as a porous medium, and then serve as the two most important parameters for studying the goaf: the viscous resistance coefficient and the inertial resistance coefficient are important to accurately measure the two parameters.
In terms of testing these two parameters, the patent (CN 201710113586.6) provides a measuring device for the viscous resistance coefficient and the inertial resistance coefficient of a porous medium material, which solves these two parameters by polynomial fitting by testing the pressure difference between two ends of the porous medium and the wind speed before flowing through the porous medium. The patent (CN 201410777349.6) provides a device for measuring the viscous resistance coefficient and the inertial resistance coefficient of oil-water migration in soil, and the two parameters are solved by polynomial fitting by testing the pressure difference between two ends of a porous medium and the flow rate before flowing through the porous medium. The patent (CN 201710560756.5) provides a method for measuring the coefficient of flow resistance of tobacco shreds to mainstream smoke, the velocity of the mainstream smoke is calculated by using a PIV system experiment, the pressure difference between the two ends of an inlet and an outlet of the tobacco shreds is measured by using a pressure gauge, and then the two parameters are solved by polynomial fitting.
The wide range of scholars provide different testing means and devices according to the research needs, but the devices can only test static porous media, namely, the research object is static and the pore structure can not be changed. And for the coal mine goaf, the pore structures at different positions are different. The current testing equipment can not continuously test the viscous resistance coefficient and the inertia resistance coefficient under different porosities.
Disclosure of Invention
An object of the utility model is to provide a hydraulic pressure loading formula viscous drag coefficient and inertial drag coefficient testing arrangement.
The utility model adopts the technical proposal that:
a hydraulic loading type viscous resistance coefficient and inertial resistance coefficient testing device comprises an experiment tube and an air tube, wherein one end of the experiment tube is connected with the other end of the air tube through a flange, a pressing plate is arranged on the inner wall of the other end of the experiment tube in a sliding mode, gangue with a certain particle size is filled in the experiment tube between the inner side of the pressing plate and the flange at one end of the experiment tube, a push rod with scales is connected to the opposite outer side of the pressing plate, the push rod is driven by a hydraulic machine, the pressing plate moves back and forth along the axial direction of the experiment tube under the driving of the push rod to change gaps among the gangue to form porous media with different porosity, a differential pressure gauge is arranged on the experiment tube, two probes of the differential pressure gauge are correspondingly arranged at two ends of a gangue filling area, one end of the air tube is respectively connected with a fan and a vacuum pump, an anemometer and a vacuum, the differential pressure gauge, the anemometer and the vacuum gauge are all connected with a signal acquisition instrument.
Furthermore, one end of the experiment pipe is provided with an experiment pipe flange, the other end of the air pipe is provided with an air pipe flange, and the experiment pipe flange and the air pipe flange are connected and matched; one probe of the differential pressure meter is arranged on the outer side of the pressing plate, and the other probe of the differential pressure meter is arranged on one side of the air pipe close to the air pipe flange plate.
furthermore, the access ports of the differential pressure gauge, the anemometer, the vacuum meter, the fan and the vacuum pump are all provided with control valves.
Furthermore, a protective net is arranged in the middle of the flange of the experiment pipe, and the diameter of a round hole in the protective net is smaller than the size of the selected gangue.
furthermore, circular holes are uniformly formed in the pressing plate, and the diameter of each circular hole is smaller than the size of the selected gangue.
Furthermore, one end of the air pipe is respectively connected with the fan and the vacuum pump through a connecting pipe, the connecting pipe is a three-way connecting pipe, and the connecting pipe is formed by PVC materials.
Further, the experiment pipe and the air pipe are fixedly arranged on the plurality of pillars.
Further, the cross section of experiment pipe is the square, and the round hole of a certain amount has been seted up to the experiment pipe equidistance, and the round hole is used for installing the differential pressure gauge so that the probe homoenergetic of differential pressure gauge sets up in the clamp plate outside under the condition of different porosities, and the experiment pipe all adopts the steel sheet shaping.
Further, it still includes rubber buffer and the closing plate that is used for airtight experiment, the closing plate replaces the clamp plate when the gas tightness test and seals the other end of experiment pipe, and the rubber stopper seals unnecessary round hole on the experiment pipe when the gas tightness test.
the test method of the hydraulic loading type viscous resistance coefficient and inertia resistance coefficient test device comprises the following steps:
Step 1, assembling a testing device, sealing redundant round holes of an experiment tube by using a rubber plug, sealing the other end of the experiment tube by using a sealing plate, and keeping all control valves in a closed state;
And 2, carrying out air tightness test: opening a vacuum pump valve and a vacuum meter valve, and vacuumizing the pipeline by using a vacuum pump to ensure that the vacuum indication number is less than-0.09 MPa;
Step 3, observing the number of vacuum representations within one hour;
When the number of the vacuum meters does not change within one hour, the tightness of the testing device is good, and step 4 is executed;
When the reading of the vacuum gauge changes greatly or returns to 0 within one hour, the test device is poorly sealed and step 1 is performed;
And 4, carrying out an initial wind resistance test: the sealing plate is detached, the vacuum meter valve and the vacuum pump valve are closed, the fan valve is opened, the pressure plate is placed in the experiment pipe to a certain depth, two ends of the differential pressure gauge are respectively arranged on the outer side of the pressure plate and the flange of the experiment pipe, and the differential pressure gauge and the anemometer are connected to the information acquisition instrument; then the fan is started and the rotating speed of the fan is adjusted, the self resistance of the system is tested under the condition of different wind speeds, and a value Pi is recorded, wherein i represents different wind speeds;
And 5, carrying out working wind resistance test: unloading the probe of the pressure difference meter on the experiment pipe, withdrawing the pressure lever, putting the gangue in the experiment pipe, pushing the pressure lever into the experiment pipe to make the gangue form porous media with different porosities, installing the pressure difference meter probe behind the pressure plate, testing the pressure difference under different wind speeds under certain porosity conditions, recording as Δ Pij, i representing different wind speeds, j representing different porosities, and Δ Pij-Pi representing the actual pressure difference loss of the porous media,
And 6, calculating a viscous resistance coefficient and an inertial resistance coefficient through a fitting relational expression of the pressure difference and the wind speed, finishing the experiment, dismounting the pressure difference meter, the anemometer and the vacuum pump, withdrawing the pressure lever, dumping out the gangue in the experiment pipe, and finishing the equipment.
The utility model adopts the above technical scheme, through the space that the clamp plate control waste rock occupied, and then adjust the porosity of waste rock, the porosity of different positions departments in the simulation is in the pit, and then deduces the change law of collecting space area viscidity resistance coefficient, inertial resistance coefficient, provides the foundation for seeking collecting space area gas and gush out law, smooth law. The utility model discloses simple structure is convenient for test viscous drag coefficient and inertial resistance coefficient under the different porosities in succession.
drawings
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments;
Fig. 1 is a schematic structural diagram of the hydraulic loading type viscous resistance coefficient and inertial resistance coefficient testing device of the present invention.
Fig. 2 is a schematic diagram of the state of the present invention during the sealing test process.
Fig. 3 is an elevation view of the experimental pipe flange of the present invention.
1-a hydraulic press; 2-a push rod; 3-an experimental tube; 4, pressing a plate; 5-gangue; 6-a pillar; 7-an experiment pipe flange plate and 7-1 protective net; 8-air pipe flange; 9-a valve; 10-differential pressure gauge; 11-a signal acquisition instrument; 12-an anemometer; 13-a valve; 14-vacuum gauge; 15-a valve; 16-air pipe; 17-a connecting tube; 18-a valve; 19-a fan; 20-a vacuum pump; 21-a valve; 22-sealing plate.
Detailed Description
As shown in one of figures 1-3, the utility model discloses a hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device, which comprises an experiment tube 3 and an air tube 16, wherein one end of the experiment tube 3 is connected with the other end of the air tube 16 through a flange, a pressing plate 4 is arranged on the inner wall of the other end of the experiment tube 3 in a sliding manner, gangue 5 with certain particle size is filled in the experiment tube 3 between the inner side of the pressing plate 4 and the flange at one end of the experiment tube 3, a push rod 2 with scales is connected with the relative outer side of the pressing plate 4, the push rod 2 is driven by a hydraulic machine 1, the pressing plate 4 is driven by the push rod 2 to move back and forth along the axial direction of the experiment tube 3 to change the gap between the gangue 5 to form porous media with different porosity, a differential pressure gauge 10 is arranged on the experiment tube 3, two probes of the differential pressure gauge 10 are correspondingly arranged at the two ends of a gangue 5 filling, an anemometer 12 and a vacuum meter 14 are respectively arranged on the wind pipe 16, the anemometer 12 detects the wind speed in the wind pipe 16, the vacuum meter 14 detects the vacuum degree of the wind pipe 16, and the differential pressure gauge 10, the anemometer 12 and the vacuum meter 14 are all connected with a signal acquisition instrument 11.
Specifically, the push rod 2 is provided with scales, and the experiment tube 3 is long1The length l of the push rod 2 entering the experiment tube 32the section of the experimental pipe 3 is a rectangular section, the length is a, and then the volume V occupied by the gangue 5 can be calculated1=（l1- l2）×a2Is known tothe mass m and the density rho of the waste rock 5 can be solved to obtain the volume V of the waste rock 52And (V) m/ρ, and the porosity = (V) when the plunger 2 enters into a different depth1-V2）/V1。
Furthermore, one end of the experiment tube 3 is provided with an experiment tube flange 7, the other end of the air tube is provided with an air tube flange 8, and the experiment tube flange 7 is connected and matched with the air tube flange 8; one probe of the differential pressure meter 10 is arranged on the outer side of the pressure plate 4, and the other probe of the differential pressure meter 10 is arranged on one side of the air pipe 16 close to the air pipe flange 8. The middle of the experimental pipe flange 7 is provided with a protective net 7-1.
furthermore, the inlets of the differential pressure gauge 10, the anemometer 12, the vacuum gauge 14, the fan 19 and the vacuum pump 20 are provided with control valves 9 (13, 15, 18, 21).
furthermore, circular holes are uniformly formed in the pressing plate 4, and the diameter of each circular hole is smaller than the size of the selected gangue 5.
furthermore, one end of the air pipe 16 is respectively connected with a fan 19 and a vacuum pump 20 through a connecting pipe 17, the connecting pipe 17 is a three-way connecting pipe 17, and the connecting pipe 17 is made of a PVC material.
further, the experimental pipe 3 and the wind pipe are installed and fixed on a plurality of pillars 6.
Further, the cross section of experiment pipe 3 is the square, and the equidistant round hole of having seted up a certain amount on experiment pipe 3, the round hole is used for installing differential pressure gauge 10 so that the probe homoenergetic of differential pressure gauge 10 can set up in the clamp plate 4 outside under the condition of different porosities, and experiment pipe 3 adopts steel sheet 3 shaping.
Further, it still includes rubber buffer and closing plate 22 that are used for airtight experiment, closing plate 22 replaces clamp plate 4 to seal the other end of experiment pipe 3 when the gas tightness test, and the rubber stopper seals unnecessary round hole on experiment pipe 3 when the gas tightness test.
The test method of the hydraulic loading type viscous resistance coefficient and inertia resistance coefficient test device comprises the following steps:
Step 1, assembling a testing device to ensure that redundant round holes of an experiment tube 3 are sealed by rubber plugs, the other end of the experiment tube 3 is sealed by a sealing plate 22, and all control valves are in a closed state;
specifically, the specific steps of the test device assembly are: firstly fixing a support 6 on the ground, then installing an experiment tube 3 and an air pipe on the support 6, further connecting the experiment tube 3 and the air pipe through a flange plate, respectively installing a vacuum meter 14 and an anemometer 12 on the experiment tube 3 and the air pipe, simultaneously sealing redundant through holes of the experiment tube 3 by rubber plugs, sealing one end of the experiment tube 3 by a sealing plate 22, respectively connecting one end of the air pipe with a fan 19 and a vacuum pump 20 through a connecting pipe 17, and simultaneously ensuring that all valves are in a closed state;
And 2, carrying out air tightness test: opening a valve of a vacuum pump 20 and a valve of a vacuum meter 14, and vacuumizing the pipeline by using the vacuum pump 20 to ensure that the reading number of the vacuum meter 14 is less than-0.09 MPa;
step 3, observing the number of the 14 indications of the vacuum meter in one hour;
When the indication number of the vacuum meter 14 does not change within one hour, the tightness of the testing device is good, and step 4 is executed;
When the reading of the vacuum gauge 14 changes greatly or returns to 0 within one hour, the test device is poorly sealed and step 1 is performed;
And 4, carrying out an initial wind resistance test: the sealing plate 22 is detached, the valve of the vacuum meter 14 and the valve of the vacuum pump 20 are closed, the valve of the fan 19 is opened, the pressure plate 4 is placed in the experiment pipe 3 to a certain depth, two ends of the differential pressure gauge 10 are respectively arranged on the outer side of the pressure plate 4 and the position of the experiment pipe flange 7, and the differential pressure gauge 10 and the anemometer 12 are connected to the information acquisition instrument; then the fan 19 is started and the rotating speed of the fan 19 is adjusted, the self resistance of the system under the condition of different wind speeds is tested, and a Δ Pi is recorded, wherein i represents different wind speeds;
And 5, carrying out working wind resistance test: the probe of the pressure difference meter 10 on the experiment pipe 3 is dismounted, the pressure lever is withdrawn, the gangue 5 is put in the experiment pipe 3, the pressure lever is pushed into the experiment pipe 3 to enable the gangue 5 to form porous media with different porosities, the probe of the pressure difference meter 10 is arranged behind the pressure plate 4, the pressure difference under different wind speed conditions under certain porosity conditions is tested and is recorded as Δ Pij, i represents different wind speeds, j represents different porosities, Δ Pij-Pi represents the actual pressure difference loss of the porous media,
And 6, calculating a viscous resistance coefficient and an inertial resistance coefficient through a fitting relational expression of the pressure difference and the wind speed, finishing the experiment, dismounting the differential pressure gauge 10, the anemometer 12 and the vacuum pump 20, withdrawing the compression bar, dumping the gangue 5 in the experiment pipe 3, and finishing the equipment.
the utility model adopts the above technical scheme, through the space that the clamp plate control waste rock occupied, and then adjust the porosity of waste rock, the porosity of different positions departments in the simulation is in the pit, and then deduces the change law of collecting space area viscidity resistance coefficient, inertial resistance coefficient, provides the foundation for seeking collecting space area gas and gush out law, smooth law. The utility model discloses simple structure is convenient for test viscous drag coefficient and inertial resistance coefficient under the different porosities in succession.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. Hydraulic pressure loading formula viscous drag coefficient and inertial drag coefficient testing arrangement, its characterized in that: the device comprises an experiment pipe and an air pipe, wherein one end of the experiment pipe is connected with the other end of the air pipe through a flange plate, a pressing plate is arranged on the inner wall of the other end of the experiment pipe in a sliding mode, gangue with a certain particle size is filled in the experiment pipe between the inner side of the pressing plate and the flange plate at one end of the experiment pipe, a push rod with scales is connected to the opposite outer side of the pressing plate, the push rod is driven by a hydraulic machine, the pressing plate moves back and forth along the axial direction of the experiment pipe under the driving of the push rod to change gaps among the gangue to form porous media with different porosities, a differential pressure gauge is arranged on the experiment pipe, two probes of the differential pressure gauge are correspondingly arranged at two ends of a gangue filling area, one end of the air pipe is respectively connected with a fan and a vacuum pump, an anemometer and, the anemometer and the vacuum meter are both connected with a signal acquisition instrument.
2. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: the one end of experiment pipe is equipped with the experiment pipe ring flange, and the other end of tuber pipe is equipped with the tuber pipe ring flange, and experiment pipe ring flange and tuber pipe ring flange are connected the cooperation.
3. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 2, wherein: one probe of the differential pressure meter is arranged on the outer side of the pressing plate, and the other probe of the differential pressure meter is arranged on one side of the air pipe close to the air pipe flange plate.
4. the hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: and the access ports of the differential pressure gauge, the anemometer, the vacuum meter, the fan and the vacuum pump are all provided with control valves.
5. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: round holes are uniformly formed in the pressing plate, and the diameter of each round hole is smaller than the size of the selected gangue.
6. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: one end of the air pipe is respectively connected with the fan and the vacuum pump through a connecting pipe, the connecting pipe is a three-way connecting pipe, and the connecting pipe is formed by adopting a PVC material.
7. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: the experiment pipe and the air pipe are fixedly arranged on the plurality of pillars.
8. The hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 1, wherein: the cross section of experiment pipe is the square, and the round hole of a certain amount is seted up to experiment pipe equidistance, and the round hole is used for installing the differential pressure gauge so that the probe homoenergetic of differential pressure gauge sets up in the clamp plate outside under the condition of different porosities, and the experiment pipe all adopts the steel sheet shaping.
9. the hydraulic loading viscous drag coefficient and inertial drag coefficient testing apparatus of claim 8, wherein: it still includes rubber buffer and the closing plate that is used for airtight experiment, the closing plate replaces the clamp plate when the gas tightness test and seals the other end of experiment pipe, and rubber stopper seals unnecessary round hole on the experiment pipe when the gas tightness test.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920532756.9U CN209802916U (en) | 2019-04-18 | 2019-04-18 | Hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920532756.9U CN209802916U (en) | 2019-04-18 | 2019-04-18 | Hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device |
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| Publication Number | Publication Date |
|---|---|
| CN209802916U true CN209802916U (en) | 2019-12-17 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920532756.9U Expired - Fee Related CN209802916U (en) | 2019-04-18 | 2019-04-18 | Hydraulic loading type viscous resistance coefficient and inertia resistance coefficient testing device |
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| Country | Link |
|---|---|
| CN (1) | CN209802916U (en) |
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2019
- 2019-04-18 CN CN201920532756.9U patent/CN209802916U/en not_active Expired - Fee Related
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20191217 Termination date: 20200418 |