CN103017683A - Device and method for measuring liquid jet on outermost boundary - Google Patents
Device and method for measuring liquid jet on outermost boundary Download PDFInfo
- Publication number
- CN103017683A CN103017683A CN2012105956582A CN201210595658A CN103017683A CN 103017683 A CN103017683 A CN 103017683A CN 2012105956582 A CN2012105956582 A CN 2012105956582A CN 201210595658 A CN201210595658 A CN 201210595658A CN 103017683 A CN103017683 A CN 103017683A
- Authority
- CN
- China
- Prior art keywords
- jet
- camera
- plane
- boundary
- laser
- 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.)
- Pending
Links
Images
Abstract
The invention discloses a device and a method for measuring liquid jet on an outermost boundary. The device comprises a computer, a camera, a test section and a laser generator, jets are injected in the test section, laser sheet-light emitted by the laser generator irradiates on jet droplets, a focal plane of the camera, the laser sheet-light and an observing plane are on a same plane, the camera is used for shooting droplets in a laser plane, a camera shooting face and a laser sheet-light incident plane are transparent, the measuring device is disposed in a darkroom environment, and the computer collects shot images and binarize the images to obtain a jet boundary figure and calculates physical boundary distance information of the jet boundary figure. The method includes: A, demarcating the measuring device; B, utilizing the camera to shoot the droplets, and obtaining image results; C, converting the image results into a grayscale map, and extracting a boundary; and D, calculating the physical distance information of the jet boundary. By the device and the method for measuring liquid jet on the outermost boundary, quantitative information of the droplets, formed after the liquid jets are crushed, on the outermost boundary in a whole flow field observing plane, can be obtained.
Description
Technical field
The present invention relates to measuring method and image processing field, particularly a kind of measurement mechanism and method of obtaining hydrofluidic outermost border.
Background technology
In the engine take liquid fuel as propellant, the fragmentation of hydrofluidic and atomizing are very important processes.When the research spray of jet and atomization characteristics, the distribution of the drop that forms behind the jet crushing is a very important measurement parameter, and it has determined the blending degree of the atomizing of hydrofluidic and itself and air-flow.Jet outermost border is the outer boundary of the drop that forms behind the jet crushing maximum region that can reach.
The form of expression of the maximum extent of hydrofluidic in crossflow is the penetration depth of hydrofluidic.In the hydrofluidic fragmentation and atomization process in the research crossflow, document " Lin K C; Kennedy P J; Jackson T A.Structures of water jets in a Mach 1.94supersonic crossflow.AIAA-2004-971 " and " Thomas RH; Schetz J A.Distributions across the plume of transverse liquid and slurry jets in supersonic crossflow[J] .AIAA Journal; 1985,23 (12): 1892-1901 " penetration depth of jet is defined as jet-core region trapped fluid mist outermost profile apart from the maximum normal distance of bottom surface.Aspect the research of obtaining jet outermost border, the method that usually adopts is PDPA method, High Speed Photography, schlieren method, shadowing method and sheet light method.
The PDPA method adopts the mode of one-point measurement can obtain the local volume flow rate of the drop of jet crushing formation, and obtains the peripheral boundary of jet according to the definition of different jet boundaries.Document " Lin K C; Kennedy P J; Jackson T A.Structures of water jets in a Mach 1.94supersonic crossflow.AIAA-2004-971 " and " Wu P K; Kirkendall K A; Fuller R P; et al.Spray structure of liquid jets atomized in subsonic crossflow [J] .Journal of Propulsion and Power, 1998,14 (2); 173-182 " volume flow rate that jet peripheral boundary point in the crossflow is defined as jet is the point of 0.01cc/ (scm2) or 0.02cc/ (scm2), both are not too identical for the definition of liquid mist periphery; Simultaneously the PDPA method is taked is that single-point in the stream field is measured, the jet boundary information that its efficient is lower, be difficult to the whole flow field of disposable acquisition.
High Speed Photography, shadowing method and schlieren method can both obtain the general profile of jet main flow, document " Lai Lin. the flow field test of the super burn engine of band cavity firing chamber and simulation study [D]. Changsha: the .2003 of the National University of Defense Technology " adopt different digital image processing techniques for different measuring methods, the result who obtains is not quite similar, and document " Liu Jing; Xu Xu. horizontal liquid jetting atomization progress in the high velocity air. Proceedings of Mechanics .2009; Vol.39No.3.273-283 " point out, adopt High Speed Photography, shadowing method, the jet penetration that schlieren method obtains is less than the result of PDPA method, reason is High Speed Photography, shadowing method and schlieren method are difficult to catch the drop that becomes with the interior jet crushing-type that measures the peripheral liquid mist of jet main flow thin area, so what adopt that above method obtains is not the border of the outermost of jet.
When application sheet light method is carried out the research of jet extended boundary, document " Chaouki Ghenai; Hayri Sapmaz; Cheng-Xian Lin.Penetration height correlation for non-aerated and aerated transverse liquid jets in supersonic cross flow; Exp Fluids (2009) 49:121-129 " acts on plane of vision with laser sheet optical and at the optical information perpendicular to the location arrangements cameras record particle scattering of plane of vision, but its digital picture that sheet light method is obtained adopts the Canny method to process, be that the shade of gray threshold value of choosing is filtered to digital picture with the people namely, obtain the larger location of pixels point of shade of gray as the border of jet.The Canny method that it is used in the processing procedure of image, human factor and uncertainty are larger, and the threshold value of shade of gray is chosen the considerable influence that defines to jet boundary; Simultaneously because the CONCENTRATION DISTRIBUTION of drop is inhomogeneous, so that in the image result that sheet light method obtains, intensity profile is inhomogeneous, pixel corresponding to shade of gray maximal value is not one to fix on the jet peripheral boundary, it may be on the separation of dense liquid mist and thin liquid mist, so the Canny method is processed the not necessarily outermost border of jet of the border result that obtains; In addition, it is clear and definite not to adopt the Canny method to process the physical significance of the jet boundary that sheet light image result obtains.
As a whole, at present more for the acquisition methods on hydrofluidic border in the air-flow, but the outermost border of the jet that these methods are difficult to obtain, adopting simultaneously different digital processing methods that the image result that obtains is processed the jet boundary that obtains is not quite similar, and some observation procedure efficient is lower, is badly in need of the research method of obtaining jet outermost border of a kind of fast, efficient and quantification of development.
Summary of the invention
For the deficiencies in the prior art, the object of the present invention is to provide measurement mechanism and the method on a kind of hydrofluidic outermost border, can obtain the drop outermost peripheral amount of defining information in whole flow observation plane that the hydrofluidic fragmentation forms afterwards.
The measurement mechanism on a kind of hydrofluidic outermost of the present invention border comprises computing machine 1, camera 8, test section 7, laser generator 2.
Utilize the measuring method on a kind of hydrofluidic outermost border of said apparatus, may further comprise the steps:
Further, in the described step 3 two-value to be treated to and to adopt gray threshold be 0 two-value disposal route.
Further, described step 3 also comprises negative process after extracting the border.
Because the present invention adopts laser sheet optical that whole flow field is observed, so the present invention is more simpler, quick than the single-spot way of PDPA; Simultaneously because the gray threshold that image is processed among the present invention is chosen for 0, so with respect to High Speed Photography, shadowing method, the more unique and quantification of the resulting result of schlieren method; The present invention is according to the be scattering into picture of drop to laser in addition, and the image processing method physical significance in higher speed Photographic technique, shadowing method, schlieren method and the sheet light method is clearer and more definite.
Description of drawings
Fig. 1: the measuring method process flow diagram on a kind of hydrofluidic outermost of the present invention border
Fig. 2: the measurement mechanism structural representation on a kind of hydrofluidic outermost of the present invention border
Fig. 3: the laser sheet optical test findings figure that utilizes the present invention to obtain
Fig. 4: laser sheet optical test findings figure is carried out two-value result figure
Fig. 5: Boundary Extraction is figure as a result
Embodiment
Below in conjunction with accompanying drawing the present invention is described in detail.
Present embodiment is the measurement mechanism on a kind of hydrofluidic outermost border, and its structural representation as shown in Figure 2.Comprise computing machine 1, camera 8, test section 7, laser generator 2.
Jet is from test section 7 bottoms ejections, deviation, fragmentation under the effect of air-flow 4, is atomized into droplet, and camera 8 is used for taking droplet; Laser generator 2 sends laser sheet optical 3 and is radiated on the droplet, and the focal plane 6 of camera 8, laser sheet optical 3 are in same plane with the plane that will observe.Camera 8 shooting faces and laser sheet optical 3 planes of incidence of test section 7 correspondences are transparent, and its lap blacking keeps testing laboratory's darkroom environment, prevent reflection and the interference of laser beyond the test section plane of vision, prevent that the external interference light signal from entering camera 8.The opening and closing of computing machine 1 control laser generator 2 gather the captured image of camera 8 simultaneously.
The effect of jet by air-flow 4 forms droplet, opens laser generator 2, and laser sheet optical 3 irradiations are come, as long as the position that has drop to exist, drop will scattering laser, makes laser signal enter camera 8 imagings, and the gray-scale value of respective pixel is not 0; The position that does not have drop, scattering laser not, the gray-scale value of camera 8 imaging respective pixel is 0.Computing machine is processed imaging, obtains its border.
The present embodiment introduction be to utilize air-flow 4 that jet is formed droplet, can also be by other modes such as nozzle formation droplet that directly atomizes.
Utilize said apparatus to measure the method on hydrofluidic outermost border, as shown in Figure 1.Specifically may further comprise the steps:
Regulate focal length and the laser sheet optical plane of camera, make focal plane 6, laser plane 3 and the institute's plane of vision of wanting coincidence of camera, focus finish after, obtain scale corresponding to plane of vision pixel distance and physical distance.Then, guarantee that whole measurement mechanism and measuring process are in the environment of darkroom, do not add any drop in the flow field, open laser instrument, test shooting, obtain image result, all pixel gray-scale values are 0 in the image result.
Open laser instrument; Test section 7 interior stream penetratings pass into gas 4, and jet deviation, fragmentation, atomizing form droplet; Utilize 8 pairs of jets of camera and droplet to take, obtain image result.Fig. 3 is the image of the drop scattering laser sheet light that obtains.In the measuring process, adjust the size of camera 8 apertures and the size of laser instrument 2 energy, make the image result that obtains clear and without over-exposed phenomenon.
Change gained image result in the step 2 into gray-scale map first, because gray scale is for the some grades that are divided into according to logarithmic relationship between white and the black, and gray scale is divided into 256 rank of 0-255, and gray-scale value is 0 expression black, gray-scale value is 255 expression whites, and the image that represents with gray scale is called gray-scale map.Adopting gray threshold is that 0 two-value disposal route is carried out two-value to this gray-scale map and processed, and namely all gray-scale values will change 255 into greater than the gray-scale value of 0 pixel in the image, be white, and all gray-scale values to be the gray-scale value of 0 pixel still remain 0, be black.
In plane of vision, as long as the position that has drop to exist, drop will make laser signal enter camera 8 imagings by scattering laser, the corresponding pixel points gray-scale value will be greater than 0, therefore carry out corresponding grey scale value in the image after two-value is processed and be 255 pixel and be the position that drop exists, thereby obtain the droplet distribution scope, acquired results as shown in Figure 4.Adopt known Sobel boundary extraction method, acquired results carried out Boundary Extraction after above two-value was processed, and obtained the jet boundary image again.And then carry out negative process, can obtain as shown in Figure 5 more clearly jet boundary image.
According to step 1 gained scale, the pixel distance on border in the gained image result is converted into the actual physics distance, change the pixel distance information of jet into physical distance information, thereby determine the greatest physical border of jet expansion.
The present invention expands optical illumination in blocks flow field to laser beam through compound lens, use digital camera to take the flow field, according to the scattering properties of particle to laser, the instantaneous picture result of the particle in the flow field that obtains, process according to the gained image result, obtain the greatest physical border of jet expansion.
Various not illustrating the restriction of essence of an invention Composition of contents, the person of an ordinary skill in the technical field after having read instructions can to before described embodiment make an amendment or be out of shape, do not deviate from essence of an invention and scope.
Claims (4)
1. the measurement mechanism on a hydrofluidic outermost border comprises computing machine (1), camera (8), test section (7), laser generator (2);
Jet (5) sprays in the test section (7), the laser sheet optical (3) that laser generator (2) sends is radiated on the droplet of jet atomization formation, the focal plane of camera (8), laser sheet optical (2) and the plane that will observe are in same plane, and camera (8) is used for taking the droplet in the laser plane; Camera (8) shooting face and laser sheet optical (3) plane of incidence that test section (7) is corresponding are transparent, whole measurement mechanism is in the darkroom environment, and computing machine (1) gathers the captured image of camera (8), the image of taking is carried out the physical distance information that the two-value processing is obtained jet boundary figure, calculated jet boundary.
2. utilize the measuring method on a kind of hydrofluidic outermost border of claim 1, may further comprise the steps:
Step 1, calibration measurements device obtain scale corresponding to plane of vision pixel distance and physical distance;
Step 2, utilize camera (8) that droplet is taken, obtain image result;
Step 3, the image result during with the resulting jet stability of step 2 are converted into gray-scale map, again this gray-scale map are carried out two-value and process, and extract the border;
Step 4, the scale that obtains according to step 1 calculate the physical distance information of jet boundary.
3. the measuring method on a kind of hydrofluidic outermost as claimed in claim 2 border is characterized in that: to be treated to and to adopt gray threshold be 0 two-value disposal route to two-value in the described step 3.
4. the measuring method on a kind of hydrofluidic outermost as claimed in claim 2 border, it is characterized in that: described step 3 also comprises negative process after extracting the border.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012105956582A CN103017683A (en) | 2012-12-31 | 2012-12-31 | Device and method for measuring liquid jet on outermost boundary |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012105956582A CN103017683A (en) | 2012-12-31 | 2012-12-31 | Device and method for measuring liquid jet on outermost boundary |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103017683A true CN103017683A (en) | 2013-04-03 |
Family
ID=47966562
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012105956582A Pending CN103017683A (en) | 2012-12-31 | 2012-12-31 | Device and method for measuring liquid jet on outermost boundary |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103017683A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104501737A (en) * | 2014-12-19 | 2015-04-08 | 中国人民解放军国防科学技术大学 | Device and method for positioning boundary of liquid jet spray |
| CN104569482A (en) * | 2014-12-31 | 2015-04-29 | 江苏大学 | Surface speed measurement device and method for high-speed liquid jet |
| CN105241381A (en) * | 2015-10-09 | 2016-01-13 | 中国水产科学研究院东海水产研究所 | Method for measuring mouth of trawlnet model |
| CN105547185A (en) * | 2016-01-15 | 2016-05-04 | 中国人民解放军国防科学技术大学 | Method for obtaining lateral jet boundary of liquid |
| CN108548817A (en) * | 2018-03-26 | 2018-09-18 | 清华大学 | Multiphase bouyant jet tests generating means and oil droplet bubble shadow image processing method |
| CN110234981A (en) * | 2017-01-16 | 2019-09-13 | 阿普塔尔法国简易股份公司 | Analysis is as distributing method spraying caused by the device of fluid medicine |
| CN113203359A (en) * | 2021-03-23 | 2021-08-03 | 上海工程技术大学 | Fog column automatic check out system based on machine vision |
| CN114935310A (en) * | 2022-05-06 | 2022-08-23 | 北京航空航天大学 | Device and method for measuring micro displacement of liquid jet surface |
| CN114937401A (en) * | 2022-05-06 | 2022-08-23 | 北京航空航天大学 | Hydrodynamics experiment system and method for eliminating liquid jet total reflection area |
| CN115988342A (en) * | 2023-03-20 | 2023-04-18 | 中国空气动力研究与发展中心计算空气动力研究所 | Device, method, system and medium for shooting flow display image |
-
2012
- 2012-12-31 CN CN2012105956582A patent/CN103017683A/en active Pending
Non-Patent Citations (6)
| Title |
|---|
| CHAOUKI GHENAI等: "Penetration height correlations for non-aerated and aerated transverse liquid jets in supersonic cross flow", 《EXPERIMENTS IN FLUIDS》 * |
| PEI-KUAN WU等: "Spray Structures of Liquid Jets Atomized in Subsonic Crossflows", 《JOURNAL OF PROPULSION AND POWER》 * |
| THOMAS RH等: "Distributions across the plume of transverse liquid and slurry jets in supersonic crossflow", 《AIAA JOURNAL》 * |
| 刘静等: "高速气流中横向液体射流雾化研究进展", 《力学进展》 * |
| 吕为等: "新型双出口合成射流激励器的流场特征研究", 《实验流体力学》 * |
| 王嘉梅: "《基于MATLAB的数字信号处理与实践开发》", 31 December 2007 * |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104501737A (en) * | 2014-12-19 | 2015-04-08 | 中国人民解放军国防科学技术大学 | Device and method for positioning boundary of liquid jet spray |
| CN104569482A (en) * | 2014-12-31 | 2015-04-29 | 江苏大学 | Surface speed measurement device and method for high-speed liquid jet |
| CN104569482B (en) * | 2014-12-31 | 2018-01-16 | 江苏大学 | A kind of high-velocity liquid jet superficial velocity measurement apparatus and method |
| CN105241381A (en) * | 2015-10-09 | 2016-01-13 | 中国水产科学研究院东海水产研究所 | Method for measuring mouth of trawlnet model |
| CN105547185A (en) * | 2016-01-15 | 2016-05-04 | 中国人民解放军国防科学技术大学 | Method for obtaining lateral jet boundary of liquid |
| CN105547185B (en) * | 2016-01-15 | 2018-03-09 | 中国人民解放军国防科学技术大学 | The acquisition methods on liquid transverse jet border |
| CN110234981A (en) * | 2017-01-16 | 2019-09-13 | 阿普塔尔法国简易股份公司 | Analysis is as distributing method spraying caused by the device of fluid medicine |
| CN108548817A (en) * | 2018-03-26 | 2018-09-18 | 清华大学 | Multiphase bouyant jet tests generating means and oil droplet bubble shadow image processing method |
| CN108548817B (en) * | 2018-03-26 | 2021-08-03 | 清华大学 | Multiphase floating jet experiment generating device and oil drop bubble shadow image processing method |
| CN113203359A (en) * | 2021-03-23 | 2021-08-03 | 上海工程技术大学 | Fog column automatic check out system based on machine vision |
| CN114935310A (en) * | 2022-05-06 | 2022-08-23 | 北京航空航天大学 | Device and method for measuring micro displacement of liquid jet surface |
| CN114937401A (en) * | 2022-05-06 | 2022-08-23 | 北京航空航天大学 | Hydrodynamics experiment system and method for eliminating liquid jet total reflection area |
| CN114937401B (en) * | 2022-05-06 | 2023-03-14 | 北京航空航天大学 | Hydrodynamics experiment system and method for eliminating liquid jet total reflection area |
| CN114935310B (en) * | 2022-05-06 | 2023-03-14 | 北京航空航天大学 | Device and method for measuring micro displacement of liquid jet surface |
| CN115988342A (en) * | 2023-03-20 | 2023-04-18 | 中国空气动力研究与发展中心计算空气动力研究所 | Device, method, system and medium for shooting flow display image |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103017683A (en) | Device and method for measuring liquid jet on outermost boundary | |
| CN104501737B (en) | A kind of device and method of liquid jet spraying boundary alignment | |
| Tian et al. | A 3D LIF system for turbulent buoyant jet flows | |
| CN103033133B (en) | A kind of acquisition methods of oscillatory boundary of jet in cross-flow of liquid | |
| Zhou et al. | Study on imaging method for measuring droplet size in large sprays | |
| He et al. | Simultaneous density and velocity measurements in a supersonic turbulent boundary layer | |
| JP2008180630A (en) | Fluid measuring system, fluid measuring method and computer program | |
| CN110118143A (en) | A kind of drop point test device and method by spraying | |
| Hijazi et al. | The use of high-speed imaging systems for applications in precision agriculture | |
| Knorsch et al. | Comparison of shadowgraph imaging, laser-Doppler anemometry and X-ray imaging for the analysis of near nozzle velocities of GDI fuel injectors | |
| Gomez et al. | Time-resolved volumetric (4D) laser induced fluorescence imaging of primary spray breakup | |
| Berthoumieu | Experimental study of supercooled large droplets impact in an icing wind tunnel | |
| Geipel et al. | Characterization of flame front structure in a dual-mode scramjet combustor with OH-PLIF | |
| Schulz et al. | A measuring system for monitoring multi-nozzle spraying tools | |
| Titov et al. | Development of optical remote sensing technique for monitoring of water basins | |
| Acharya et al. | Fluorescent PIV using atomized liquid particles | |
| Deshmukh et al. | Studies on microscopic structure of diesel sprays under atmospheric and high gas pressures | |
| Kleinwächter et al. | Concept for optical full-scale measurements of ship propeller inflow and bubble size distribution | |
| Conrad et al. | Influence of nozzle geometry parameters on the propagation of fuel spray investigated with linear and non-linear regression models | |
| Binjuwair et al. | In-Cylinder Flow Structure Analysis by Particle Image Velocimetry Under Steady State Condition | |
| Lewińska | Analysis of measurement methods for fuel injection spray parameters from marine engine injector | |
| CN114170294A (en) | Liquid fuel spray area discrimination and transient evaporation amount calculation method based on ballistic light imaging | |
| Murphy et al. | Droplet sizing and imaging of agricultural sprays using particle/droplet image analyses | |
| De Cock et al. | Agricultural spray measurement by high-speed shadow imagery | |
| Steinvall et al. | Identification of handheld objects and human activities in active and passive imaging |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130403 |