Method for measuring effective diffusion coefficient and porosity of porous medium
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
A technology of diffusion coefficient and porous medium, applied in the field of testing, can solve the problems of toxicity of test gas, cumbersome measurement, difficult to measure quickly and accurately, etc.
Inactive Publication Date: 2012-06-20
DALIAN JIAOTONG UNIVERSITY
View PDF2 Cites 27 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
The method for measuring the porosity of porous materials in the prior art is generally the pressure-volume method. The disadvantage of this method is that the measurement is cumbersome, it is not easy to measure quickly and accurately, it cannot adapt to the actual needs of chemical industry and scientific research, and the test gas is toxic. Hazardous to human body and environment
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
Click on the blue label to locate the original text in one second.
Reading with bidirectional positioning of images and text.
Smart Image
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0084] The liquid with ethanol as component A and air as component B, first measure the diffusion coefficient D of ethanol vapor in air AB , and then measure the effective diffusion coefficient D of ethanol vapor in the porous carbon paper ABP .
[0085] D ABP = ρ AL RTl p BM , p M A θ · z - z 0 p AX - p A 2
[0086] Determination of effective diffusion coefficient D of ethanol vapor in porous carbon paper ABP ...
Embodiment 2
[0137] Taking water as component A of liquid and component B as air, first measure the diffusion coefficient D of water vapor in air under different conditions AB , and then measure the effective diffusion coefficient D of water vapor in the porous carbon paper ABP .
[0138] Determination of effective diffusion coefficient D of water vapor in porous carbon paper ABP The parameters of are as follows:
[0139] R——gas constant, 8.314×10 3 N m / (kmol K);
[0140] m A - the molar mass of component A (water), 18.09kg / kmol;
[0141] θ——component A (water) liquid level in the evaporation tube by z 0 The time taken to drop to z, 18000s;
[0144] p AX ——Partial pressure of component A (water) under different conditions (calculated from formula (7)), Pa;
[0145] ρ AL ——Density of component A (water) at different temperatures, kg / m 3 ;
[0146] ...
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
Property
Measurement
Unit
thickness
aaaaa
aaaaa
Login to view more
Abstract
A method for measuring the effective diffusion coefficient and the porosity of a porous medium includes steps as follows: using an evaporation tube method to measure the binary gas diffusion coefficient DAB of component A in component B and the effective diffusion coefficient DABP of component A in the measured porous medium, utilizing the relation between DAB and DABP to work out the ratio epsilon/tau of the measured porous medium porosity to the tortuosity factor, and obtaining the porosity of the measured porous medium according to the tortuosity factor tau. The invention has the advantageof rapidly and accurately measuring the porosity of the porous medium and the effective diffusion coefficient of a gas in the porous medium, thereby providing conditions for chemical engineering and scientific research practice.
Description
technical field [0001] The invention belongs to the technical field of testing, in particular to a method for measuring the effective diffusion coefficient and porosity of porous media. Background technique [0002] Diffusion processes pervade various fields of chemical engineering, such as catalysis, adsorption, and membrane separation processes, where the diffusion of fluid mixtures in porous media is a decisive factor in determining process performance. Diffusion of gas in porous media is different from diffusion in free media. Due to the resistance of solid media, the corresponding diffusion coefficient will decrease. Different porous materials have different porosity and tortuosity factors. Therefore, it is of great significance to accurately and quickly measure the porosity of porous materials and the effective diffusion coefficient of gas in porous media in chemical engineering and scientific research. The method for measuring the porosity of porous materials in the...
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
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to view more