Device and method for measuring molecular diffusion coefficient in gas medium

A technology of molecular diffusion and gas medium, applied in measurement devices, analytical materials, instruments, etc., can solve the problem of no effective method, and achieve the effect of improving the measurement signal-to-noise ratio

Active Publication Date: 2014-07-16
NORTHWEST INST OF NUCLEAR TECH
View PDF5 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For the measurement of molecular diffusion coefficient in gaseous media under general non-static conditions, especially in combustion environment, there is no effective method at present

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
  • Device and method for measuring molecular diffusion coefficient in gas medium
  • Device and method for measuring molecular diffusion coefficient in gas medium
  • Device and method for measuring molecular diffusion coefficient in gas medium

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment

[0037] Figure 4 It is a device for measuring molecular diffusion coefficient in gas medium based on the principle of OH dissociation. The marking laser is generated by an ArF excimer laser with a wavelength of 193nm, a single pulse energy of about 30mJ, and a pulse width of 20ns. The marking laser is used to dissociate H in the measured gas medium 2O, producing OH. The displayed laser is generated by a tunable dye laser system with a wavelength of 282nm, a single pulse energy of about 2mJ, and a pulse width of 8ns. Through wavelength tuning, the display laser can be resonantly absorbed by OH and generate corresponding fluorescent radiation. The central wavelength of OH fluorescence radiation is 310nm, and the width is about 10nm.

[0038] The ICCD camera used to detect the spatial distribution of OH, the exposure time is 20ns, and a filter is placed in front of the camera lens to filter out various background interferences. The time delay adjustment device used is a digi...

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

PropertyMeasurementUnit
wavelengthaaaaaaaaaa
widthaaaaaaaaaa
wavelengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a device and a method for measuring a molecular diffusion coefficient in a gas medium. The device comprises a mark laser, a display laser, an ICCD (Intensified Charge Coupled Device) camera and a delay generator, wherein output laser of the mark laser is shaped as a mark linear laser beam; an output laser beam of the display laser is shaped as a sheet-shaped display laser beam; the mark linear laser beam is arranged in a plane of the sheet-shaped display laser beam; the sheet-shaped display laser beam is positioned in the gas medium to be detected; the ICCD camera directly faces to the sheet-shaped display laser beam; three paths of delay output ends of the delay generator are respectively connected with the mark laser, the display laser and the ICCD camera. The invention establishes a new molecular diffusion observing method. The observation method is capable of accurately measuring the molecular diffusion process under the unstable condition; the observation method can be used for observing the diffusion process of part of the molecules which are not observed by the prior art, thereby measuring the diffusion coefficient of the gas molecule.

Description

technical field [0001] The invention belongs to the observation of molecular diffusion process, in particular to a device and method for measuring molecular diffusion coefficient in gas medium. Background technique [0002] For a gas mixture composed of two or more molecules, as long as their relative concentrations are different between points, there must be a spontaneous diffusion process to reduce the heterogeneity of the components. This kind of macroscopic mass transfer independent of any convection inside the system is defined as molecular diffusion. Diffusion is caused by the random motion of molecules that will lead to complete mixing. The basic mathematical model describing diffusion - Fick's law of diffusion introduces the diffusion coefficient, which is a physical quantity that expresses the diffusion ability of a substance. Diffusion coefficient is a key parameter in the study of diffusion process, therefore, the measurement of diffusion coefficient becomes one ...

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): G01N13/00
Inventor 张振荣李国华叶景峰胡志云邵珺刘晶儒叶锡生
Owner NORTHWEST INST OF NUCLEAR TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap