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Gas hydrate is today the world's major potential energy. In recent years, the hydrate exploration recognition technology has gradually become a hot research topic in geophysics. This paper, the penetration as reflect hydrate nature of the target parameters exploring through the SDR model and Darcy's law and Poiseuille equation combined with the hydrate formation permeability with hydrate saturation relationship, in order for the identification of gas hydrate new reserves estimated explore. This paper studies the SDR model of the nuclear magnetic resonance, including the basic principles of nuclear magnetic resonance, the specific process parameters T 2 distribution spectra and NMR porosity the φN MR measurements calculated, and the NMR experiments. On this basis, a review of previous experimental results, analysis of the growth characteristics of hydrate in porous media, the establishment of a numerical simulation of the SDR model. Water, movable water bound by artificial transform ratio, porosity, permeability simulation test, and the relaxation time corresponding to explore the numerical simulation of the process, the factors restricting the penetration hydrate saturation changes. The results show that the permeability changes are not influenced by the relaxation time, but has a certain degree of contact with the proportion of bound water, movable water porosity. Subsequently, the tube - ball porous medium model represents the pore space, using a combination of Darcy's law and Poiseuille equation method to establish a new model for calculation of permeability. In this process, the first pores in series and parallel connection structure, and the hydrate formation process as a process of throwing the ball to the pore space, and from microscopic to explore the hydrate growth and pore connectivity The impact of changes in permeability. Body porosity, pore channel permeability through the introduction of the nucleation rate mechanism analysis confirmed the crucial influence of the pore channels of fluid flow capacity. Previous experimental studies have shown that, with increasing hydrate saturation, the penetration rate of descent is not fixed, and even, in some of hydrate saturation within a penetration rate essentially unchanged. This as a reference, the results of all of the analog contrast compare. And discovered that, when using SDR model, the numerical simulation of the permeability curve and Masuda model N = 10 when the results are similar, but larger difference Minagawa experiment. Using Darcy's law and Poiseuille equation, the penetration rate of the analog value is slightly higher, but the trend of of Minagawa experimental results are consistent will appear flat stages of the penetration. In particular, when hydrate crystals into the pore channel priority, the higher the probability of priority, the greater penetration of flat range.
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