Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for measuring particle diameter

A technology of particle size and particle size, which is applied in the field of particle size optical measurement, can solve the problems affecting the determination of particle diameter, high requirements for laser intensity stability, and affecting particle image point size, so as to avoid the limitation of laser light intensity and improve the image Quality, the effect of eliminating systematic errors

Inactive Publication Date: 2008-07-30
TONGJI UNIV
View PDF0 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that various digital image analysis preprocessing methods will affect the size of the particle image point, thereby affecting the determination of the true size of the particle diameter; at the same time, this method has high requirements for the stability of the laser intensity. Once the laser intensity changes , it is necessary to reset various digital image analysis and processing methods; in addition, particle imaging is also affected by laser diffraction and PIV system errors

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for measuring particle diameter
  • Method for measuring particle diameter
  • Method for measuring particle diameter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0019] The present invention will be described in further detail below in conjunction with the embodiment of measuring the particle size information of the tracer particles added in the flow field of the tank:

[0020] (1) Since the flow velocity of the flume flow field is slow, the particles in the flow field are relatively large and sparse, and the measurement resolution is not high, so the parameters of the particle image velocity field instrument imaging system used for grayscale statistical discrimination query are set As follows: the wavelength of the laser light emitted by the semiconductor pumped continuous laser is λ=532nm, the side length of the square hole of the orifice plate installed in front of the camera lens used is b′=14mm, and the vertical distance from the camera lens to the laser light path is d 1 =500mm, the angle between the laser light path and the axis of the camera lens is θ 0 =90°, laser sheet light pulse width is camera two exposure time t 1 = 5ms ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a method of measuring a particle diameter by utilizing gray level difference of particle images, and belongs to the technical field of optical measurement of the particle diameter. The method utilizes an imaging system of a particle image speed field apparatus to obtain the particle images with gray level difference, wherein, the particle images are formed in the way that a flow field is exposed twice, and the imaging system of the particle image speed field apparatus is used for distinguishing and enquiring gray level statistics. The particle images are pretreated by using an image treatment technology, and a method of using particle image gray level autocorrelation to measure the particle velocity is used to realize that one same particle is performed exposure twice to be conjugated with image points of corresponding two particles. The size of the particle diameter can be obtained by the total gray level of the image points of the two particles via a solution formula of the particle diameter, so the particle diameter information of entire flow field is obtained. By using the invention, the demand of the stability of laser intensity is lowered, and the systematic errors and the affection of digital image treatment technology and laser diffraction on measuring results of the particle diameter are reduced. Besides, the invention overcomes the shortcoming and the defection in the prior art and has substantial characteristics and obvious improvement.

Description

technical field [0001] The invention belongs to the technical field of particle size optical measurement, and relates to a method for measuring particle size in a flow field, in particular to a method for measuring particle size in a flow field by using a particle image velocity field instrument (PIV) to take a particle image in a flow field and using the difference in gray scale of the particle image Methods. Background technique [0002] The experimental measurement of particle size and velocity distribution is the main content of flow field display and its quantitative analysis. PIV (Particle Image Velocimetry) integrates computer image processing and optical technology. It has the advantages of being able to measure the transient velocity of the entire flow field in the research space and has little interference with the flow field. It has become a test and analysis of flow field. Very effective tool. However, PIV technology cannot be used for particle size measurement...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01B11/10G06T7/00
Inventor 吴志军田志松黄成杰李理光
Owner TONGJI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com