Study On Structure Characteristics Of Porous Media Based On Image Analysis-bituminous Coal And Rubble

The porous medium is a media with lots of pores inside, which is widely used inthe areas of chemical, metallurgy, building materials, oil exporation, nuclear reactions,aerospace and so on. The structure of porous media is the basis of porous mediaapplications, which determines the porous medium flow, heat and mass transfer,chemical reactions and so on. Therefore, the study of the structure characteristics ofporous media has important significance on people’s livelihood and engineeringapplications.Basis on digital image processing and analysis method, appling IPP and MATLABsoftware, this paper extracted and analyzed the average diameter, pore area percentage,pore area, pore radius ratio, pore fractal dimension and outline fractal dimension ofpores in bituminous coal and rubble heap. Therefore, this paper obtained the changinglaw of number of pores, percentage of pore area, pore area, pore perimeter and poreradius ratio along with pore diameter. Moreover, this paper summarized the relationshipof total porosity and outline fractal dimension, total porosity and pore fractal dimensionof the bituminous coal. Finally, this paper compared and analyzed similarities anddifferences of the pore structure parameters of two kinds of random porous media.The studies show that:(1) The curve trend of the number of pores in two kinds ofrandom porous media is similar, the pore number are dramatically decrease when porediameter is small, then slightly increase when the pores become big. The number ofpores is (relative) small pores>(relative) middle pores>(relative) big pores. Theresults show that the pore distribution of bituminous coal and rubble is similar.(2) Thecurve trend of pore area of two kinds of random porous media is similar. The pore areaincreased with the increase of pore diameter.(3) The curve trend of pore area percentageand pore radius ratio of two kinds of random porous media is obviously different.(4)The mean porosity in descending order: bituminous coal500X (7.2223%), bituminous coal1000X (6.8050%), rubble (6.2292%), bituminous coal2000X (5.3979%),bituminous coal3000X (5.0721%).(5) The outline fractal dimension of two kinds ofrandom porous medium is relatively consistent, which shows that the internal channelcharacteristics of two kinds of random porous medium is similar. The pore fractaldimension of rubble is bigger than bituminous coal, which suggests that both of porousmedium have differences on pore size distribution. And, the pore fractal dimension oftwo kinds of random porous medium is bigger than outline fractal dimension.(6) Forthe same bituminous coal samples total porosity, pore average diameter, pore perimeterand pore area increase with the decrease of the magnification times. However, poreradius ratio fistly increases and than decreases.