CN112834165B - Device and method for testing drag force of liquid drop along fiber axial direction airflow - Google Patents
Device and method for testing drag force of liquid drop along fiber axial direction airflow Download PDFInfo
- Publication number
- CN112834165B CN112834165B CN202011644140.4A CN202011644140A CN112834165B CN 112834165 B CN112834165 B CN 112834165B CN 202011644140 A CN202011644140 A CN 202011644140A CN 112834165 B CN112834165 B CN 112834165B
- Authority
- CN
- China
- Prior art keywords
- fiber
- drag force
- axial
- weight
- theta
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M10/00—Hydrodynamic testing; Arrangements in or on ship-testing tanks or water tunnels
Abstract
The invention discloses a liquid drop axial airflow drag force experiment device which comprises a high-pressure air source, an electromagnetic valve, a steady flow circular tube, a fiber, a first support plate, a second support plate, a first strain gauge, a second strain gauge, a weight, liquid drops, a data acquisition card and a computer, wherein the high-pressure air source is connected with the electromagnetic valve, the electromagnetic valve is connected with the steady flow circular tube, the fiber is arranged at the air outlet end of the steady flow circular tube, the two ends of the fiber are respectively fixed on the first support plate and the second support plate, the first strain gauge and the second strain gauge are respectively adhered on the first support plate and the second support plate, the first strain gauge and the second strain gauge are respectively connected with a voltage signal and the data acquisition card, the data acquisition card is connected with the computer, and the weight is hung on the fiber. The invention can accurately obtain the airflow drag force of liquid drops along the axial direction of the fiber, and has the advantages of simple structure, environmental protection, energy saving and low manufacturing cost.
Description
Technical Field
The invention relates to the field of measurement of dynamic drag force of air flow on liquid drops, in particular to an experimental device and method for drag force of liquid drops on air flow along the axial direction of fibers.
Background
The behaviors of deformation, movement and the like of liquid drops under the action of airflow are widely existed in real life, such as spraying in industry and spraying process in agriculture.
When the liquid drops on the fibers are blown by cross wind, the liquid drops form radial drag force and axial drag force under the action of the airflow vortex street. Due to the influence of factors such as droplet shape and vortex shedding, the axial drag force is not completely and symmetrically distributed along the direction of the airflow, which causes the droplets to periodically move along the axial direction of the fiber.
Currently, there is no effective experimental measurement of the drag of the droplets along the fiber axis. Most researches assume that liquid drops are standard round spheres, fibers are standard cylinders, and the air flow drag force borne by the liquid drops is calculated by adopting an empirical formula of fluid mechanics cylindrical streaming and spherical streaming, but the air flow drag force is greatly different from the actual shape and the stress condition of the liquid drops.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a device and a method for testing the drag force of liquid drops along the axial direction of a fiber airflow.
The technical scheme of the invention is as follows: the utility model provides a liquid drop is along fibre axial air current drag experimental apparatus, includes high pressurized air source, solenoid valve, stationary flow pipe, fibre, first backup pad, second backup pad, first foil gage, second foil gage, weight, liquid drop, data acquisition card and computer, high pressurized air source is connected with the solenoid valve, the solenoid valve is connected with the stationary flow pipe, the end of giving vent to anger of stationary flow pipe is equipped with the fibre, fibrous both ends are fixed respectively in first backup pad and second backup pad, paste first foil gage and second foil gage in first backup pad and the second backup pad respectively, first foil gage and second foil gage respectively with voltage signal access data acquisition card, data acquisition card is connected with the computer. Weights are hung on the fibers.
The first supporting plate and the second supporting plate are respectively arranged on the fixing support.
An experiment method based on an experiment device for liquid drop along fiber axial airflow drag force is characterized in that weights are loaded on fibers, and the distances between the weights and a first supporting plate and between the weights and a second supporting plate are L respectively a And L b Measuring F of the first and second strain gauges ya And F yb Obtaining the axial tension F of the fiber to the supporting plate ya ，F yb And L a ，L b A corresponding relation; the liquid drops are adhered to the fibers, and high-pressure gas in the high-pressure gas source enters the flow stabilizing circular tube through the electromagnetic valve to form stable gas flow; the droplets are blown by a steady transverse gas flow, subject to a radial drag force F x And axial drag force F' ya And F' yb (ii) a Calibrating F according to the weight y Corresponding to L, and calculating to obtain F' y Corresponding L' and axial drag force F experienced by the droplet ayis 。
The fiber axial tension is calibrated in the following way:
when the weight is placed on the fiber, tension is formed on two sides of the fiber, and the weight comprises the following components:
wherein G is w Weight of the weight; theta can be calculated according to the measured result by the formula 1 a And L a 、F ya Is a corresponding relation of (a), i.e. theta a ＝Θ(L a ,F ya ) (ii) a Calibration results for θ b The same applies.
The liquid drop standing force is obtained by the following method:
when the droplets rest on the fibres, tension is likewise created on both sides of the fibres, having
G d ＝F ya1 sin(θ a1 )+F yb1 sin(θ b1 ) (formula 2)
Wherein G is d Is the drop weight;
according to measured F ya1 ，F yb1 ，L a1 ，L b1 Theta can be calculated from (equation 3) a1 And theta b1 G is calculated from (formula 2) d Namely the liquid drop stress under the static condition; theta obtained by calibrating axial tension of fiber a ＝Θ(L a ,F ya ) And comparing the measured result with the measured result, and verifying the accuracy of the liquid drop standing stress result.
The axial drag force of the transverse gas flow on the liquid droplets is obtained by:
when the droplets are subjected to a transverse gas flow, a radial drag force F is generated wx And a transverse drag force F wy At this time have
From measured F ya2 ，F yb2 ，L a2 ，L b2 θ 'can be calculated from (formula 3)' a2 And θ' b2 Due to axial drag force F of the air flow wy Much smaller than G d And F wx Therefore, may be used of theta' a2 And θ' b2 Instead of theta a2 And theta b2 F can be calculated according to (equation 5) wy I.e. the airflow axial drag force.
The invention can accurately obtain the airflow drag force of liquid drops along the fiber axial direction, and has the advantages of simple structure, environmental protection, energy saving and low manufacturing cost.
Drawings
FIG. 1 is a schematic structural view of a test apparatus according to the present invention;
FIG. 2 is a schematic view of the force applied by a liquid droplet resting on a fiber;
in the figure: 1-high pressure gas source, 2-electromagnetic valve, 3-steady flow round tube, 4-fiber, 5 a-first supporting plate, 5 b-first supporting plate, 6 a-first strain gauge, 6 b-second strain gauge, 7-weight, 8-liquid drop, 9-data acquisition card, and 10-computer.
Detailed Description
The invention is further described below with reference to the accompanying drawings:
as shown in fig. 1, an experimental apparatus for droplet drag force along fiber axial direction airflow includes a high pressure gas source 1, a solenoid valve 2, a steady flow circular tube 3, a fiber 4, a first support plate 5a, a second support plate 5b, a first strain gauge 6a, a second strain gauge 6b, a weight 7, a droplet 8, a data acquisition card 9 and a computer 10, wherein the high pressure gas source 1 is connected with the solenoid valve 2, the solenoid valve 2 is connected with the steady flow circular tube 3, the air outlet end of the steady flow circular tube 3 is provided with the fiber 4, two ends of the fiber 4 are respectively fixed on the first support plate 5a and the second support plate 5b, the first support plate 5a and the second support plate 5b are respectively installed on a fixed support, the first strain gauge 6a and the second strain gauge 6b are respectively adhered on the first support plate 5a and the second support plate 5b, the first strain gauge 6a and the second strain gauge 6b are respectively connected with the data acquisition card 9, and the data acquisition card 9 is connected with the computer 10. Weights 7 are hung on the fibers 4.
As shown in figures 1 and 2, in the experimental method based on the experimental device for the airflow drag force of the liquid drops along the axial direction of the fiber, the weight 7 is loaded on the fiber 4, and the distances between the weight 7 and the first supporting plate 5a and the second supporting plate 5b are respectively L a And L b Measuring the first strain gauge 6a and the second strain gaugeF of two strain gauges 6b ya And F yb To obtain the axial tension F of the fiber 4 to the supporting plate ya ，F yb And L a ，L b A corresponding relation; the liquid drops 8 are adhered to the fibers 4, and high-pressure gas in the high-pressure gas source 1 enters the flow stabilizing circular tube 3 through the electromagnetic valve 2 to form stable gas flow; said droplets 8 being blown by a steady transverse air flow, subject to a radial drag force F x And axial drag force F' ya And F' yb (ii) a Calibrating F according to weight y Corresponding to L, and calculating to obtain F' y Corresponding L' and axial drag force F experienced by the droplet ayis 。
The axial tension of the fibre 4 is calibrated by the following means:
when the weight 7 is placed on the fibre 4, a pulling force is formed on both sides of the fibre 4, with:
wherein, G w The weight of a weight 7 is N; theta can be calculated by the formula 1 according to the measured result a And L a 、F ya In a corresponding relationship of (a), i.e. theta a ＝Θ(L a ,F ya ) (ii) a Calibration results for θ b The same applies.
The liquid drop standing force is obtained by the following method:
when the droplets 8 rest on the fibres 4, tension is likewise created on both sides of the fibres 4, with
G d ＝F ya1 sin(θ a1 )+F yb1 sin(θ b1 ) (formula 2)
Wherein G is d Is the drop weight in N;
according to measured F ya1 ，F yb1 ，L a1 ，L b1 Theta can be calculated from (equation 3) a1 And theta b1 Calculated by (equation 2)To obtain G d Namely, the liquid drop is stressed under the static condition; theta obtained by calibrating axial tension of fiber a ＝Θ(L a ,F ya ) And comparing the measured result with the measured result, and verifying the accuracy of the liquid drop standing stress result.
The axial drag of the transverse gas flow on the droplets 8 is obtained by:
when the droplets 8 are subjected to a transverse gas flow, a radial drag force F is generated wx And a lateral drag force F wy At this time have
From measured F ya2 ，F yb2 ，L a2 ，L b2 θ 'can be calculated from (formula 3)' a2 And θ' b2 Due to axial drag force F of the air flow wy Much smaller than G d And F wx Therefore, may be made of θ' a2 And θ' b2 In place of theta a2 And theta b2 F can be calculated according to (equation 5) wy I.e. the airflow axial drag force.
Claims (6)
1. The utility model provides a liquid drop is along fibre axial air current drag experimental apparatus, includes high pressurized air source (1), solenoid valve (2), stationary flow pipe (3), fibre (4), first backup pad (5 a), second backup pad (5 b), first foil gage (6 a), second foil gage (6 b), weight (7), liquid drop (8), data acquisition card (9) and computer (10), its characterized in that: high pressurized air source (1) is connected with solenoid valve (2), solenoid valve (2) are connected with stationary flow pipe (3), the end of giving vent to anger of stationary flow pipe (3) is equipped with fibre (4), it has weight (7) to hang on fibre (4), the both ends of fibre (4) are fixed respectively on first backup pad (5 a) and second backup pad (5 b), paste first foil gage (6 a) and second foil gage (6 b) on first backup pad (5 a) and second backup pad (5 b) respectively, first foil gage (6 a) and second foil gage (6 b) insert data acquisition card (9) with voltage signal respectively, data acquisition card (9) are connected with computer (10).
2. The apparatus for testing the drag force of liquid drops along the axial direction of a fiber according to claim 1, wherein: the first supporting plate (5 a) and the second supporting plate (5 b) are respectively arranged on the fixed support.
3. An experimental method based on an experimental device for droplet drag force along fiber axial direction according to any one of claims 1-2, characterized in that: the weight (7) is loaded on the fiber (4), and the distances between the weight (7) and the first supporting plate (5 a) and the second supporting plate (5 b) are L respectively a And L b Measuring F of the first strain gauge (6 a) and the second strain gauge (6 b) ya And F yb Obtaining the axial tension F of the fiber (4) to the supporting plate ya ，F yb And L a ，L b A corresponding relation; the liquid drops (8) are adhered to the fibers (4), and high-pressure gas in the high-pressure gas source (1) enters the flow stabilizing circular tube (3) through the electromagnetic valve (2) to form stable gas flow; said droplets (8) being blown by a steady transverse air flow, subject to a radial drag force F x And axial drag force F' ya And F' yb (ii) a Calibrating F according to the weight y Corresponding to L to obtain F' y Corresponding L' and axial drag force F experienced by the droplet ayis 。
4. The experimental method of claim 3, which is based on the experimental device for the drag force of the liquid drops along the axial direction of the fiber, and is characterized in that: the fiber axial tension is calibrated in the following way:
when the weight (7) is placed on the fiber (4), tension is formed on two sides of the fiber (4), and the tension comprises the following components:
wherein G is w Weight of the weight; theta can be calculated according to the measured result by the formula 1 a And L a 、F ya Is a corresponding relation of (a), i.e. theta a ＝Θ(L a ,F ya ) (ii) a Calibration results for θ b The same applies.
5. The experimental method of claim 4 based on the experimental device for the droplet drag force along the axial direction of the fiber, wherein: the liquid drop standing force is obtained by the following method:
when the liquid drop (8) is placed on the fiber (4), tension is formed on both sides of the fiber (4) in the same way, including
G d ＝F ya1 sin(θ a1 )+F yb1 sin(θ b1 ) (formula 2)
Wherein G is d Is the drop weight;
according to measured F ya1 ，F yb1 ，L a1 ，L b1 From equation 3, θ can be calculated a1 And theta b1 Calculated from equation 2 to obtain G d Namely the liquid drop stress under the static condition; theta obtained by calibrating axial tension of fiber a ＝Θ(L a ,F ya ) And comparing the measured result with the measured result, and verifying the accuracy of the liquid drop standing stress result.
6. The experimental method based on the experimental device for the airflow drag force of the liquid drops along the axial direction of the fiber as claimed in claim 5, wherein: the axial drag force of the transverse gas flow on the liquid droplets is obtained by:
when the droplets are subjected to a transverse gas flow, a radial drag force F is generated wx And a lateral drag force F wy At this time have
From measured F ya2 ，F yb2 ，L a2 ，L b2 From equation 3,. Theta.' a2 And θ' b2 Due to axial drag force F of the air flow wy Much smaller than G d And F wx Therefore, may be used of theta' a2 And θ' b2 In place of theta a2 And theta b2 F can be calculated according to equation 5 wy I.e. the airflow axial drag force.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011644140.4A CN112834165B (en) | 2020-12-31 | 2020-12-31 | Device and method for testing drag force of liquid drop along fiber axial direction airflow |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011644140.4A CN112834165B (en) | 2020-12-31 | 2020-12-31 | Device and method for testing drag force of liquid drop along fiber axial direction airflow |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112834165A CN112834165A (en) | 2021-05-25 |
| CN112834165B true CN112834165B (en) | 2023-02-03 |
Family
ID=75927204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011644140.4A Active CN112834165B (en) | 2020-12-31 | 2020-12-31 | Device and method for testing drag force of liquid drop along fiber axial direction airflow |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112834165B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113588155B (en) * | 2021-07-20 | 2023-03-28 | 杭州电子科技大学 | Fiber and liquid drop stress measuring device and method based on image identification method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104237109A (en) * | 2014-07-02 | 2014-12-24 | 南京航空航天大学 | Method and device for measuring deformation and breakage process characteristics of single liquid drop in airflow |
| CN111400978A (en) * | 2020-06-08 | 2020-07-10 | 西南石油大学 | Critical liquid carrying flow calculation method considering liquid drop deformation and multi-parameter influence |
| CN111665170A (en) * | 2020-06-16 | 2020-09-15 | 中国石油大学(华东) | Liquid drop impact experimental device for quantitatively controlling deformation and tension of flexible substrate through ventilation |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102009001526A1 (en) * | 2009-03-12 | 2010-09-16 | Endress + Hauser Flowtec Ag | A vortex flow meter for monitoring and / or measuring a distributed particle and / or droplet flow |
| WO2017079507A1 (en) * | 2015-11-06 | 2017-05-11 | Regents Of The University Of Michigan | Droplet-based microfluidic rheometer system |
| CN206348096U (en) * | 2016-12-13 | 2017-07-21 | 中国海洋大学 | A kind of experiment pulls force measuring device with heaving pile |
-
2020
- 2020-12-31 CN CN202011644140.4A patent/CN112834165B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104237109A (en) * | 2014-07-02 | 2014-12-24 | 南京航空航天大学 | Method and device for measuring deformation and breakage process characteristics of single liquid drop in airflow |
| CN111400978A (en) * | 2020-06-08 | 2020-07-10 | 西南石油大学 | Critical liquid carrying flow calculation method considering liquid drop deformation and multi-parameter influence |
| CN111665170A (en) * | 2020-06-16 | 2020-09-15 | 中国石油大学(华东) | Liquid drop impact experimental device for quantitatively controlling deformation and tension of flexible substrate through ventilation |
Non-Patent Citations (2)
| Title |
|---|
| 气井携液临界流量研究;彭朝阳;《新疆石油地质》;20100228;第31卷(第01期);第72-74页 * |
| 电场对协流式微流控装置中乳液液滴生成行为的调控机理;李蕾 等;《物理学报》;20180831;第67卷(第17期);176801 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112834165A (en) | 2021-05-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Xu et al. | Experimental investigation on multi-mode flow-induced vibrations of two long flexible cylinders in a tandem arrangement | |
| CN105527075B (en) | Method and device for moment calibration for resonance fatigue test | |
| US7424832B1 (en) | Cable tensiometer for aircraft | |
| CN105910891A (en) | Testing device for damage concrete stress-strain whole curve caused by environment corrosion | |
| CN112834165B (en) | Device and method for testing drag force of liquid drop along fiber axial direction airflow | |
| CN201152812Y (en) | Radial directional hydrodynamic-hydrostatic gas bearing experiment bench | |
| CN205879700U (en) | Gentle softness of cable detects machine | |
| CN108344645A (en) | A kind of hot bend test deflection measuring apparatus and measurement method | |
| US2782636A (en) | Internal balances for wind force measurements on aerodynamic objects | |
| CN108507753B (en) | Output signal combination method of three-component optical fiber balance | |
| CN104655002A (en) | Rock specimen deformation measurement device and radial and axial deformation measurement method | |
| JP2013516611A (en) | Device for measuring strain in components | |
| CN112129445A (en) | Bow net contact force on-line test scheme | |
| CN101349604B (en) | Apparatus and method for testing and monitoring pipe real time pressure | |
| CN207946294U (en) | Cylindrical structure transversely deforming measuring device | |
| CN205691410U (en) | The damage concrete stress strain full curve test device that environmental corrosion causes | |
| CN109342194A (en) | A kind of rock sample transversely deforming measuring device | |
| CN101413782A (en) | Double-shaft radial extensometer under high hydraulic environment | |
| CN209689818U (en) | A kind of easy force sensor caliberating device | |
| CN109693813B (en) | Ground simulation pay-off of compatible many specifications spool | |
| CN201611248U (en) | Error comparing measuring instrument for taper angle of taper hole | |
| US2785569A (en) | Wind tunnel force and moment measuring device | |
| CN114136624B (en) | Direction-adjustable thrust measurement rack center loading calibration device | |
| CN202974770U (en) | Young modulus measurer | |
| CN113607317A (en) | Indirect measuring method and system for raceway contact stress |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |