Dynamic Response Physical Simulation of Coal Reservoir Parameters During Coalbed Methane Drainage

According to the detail study on the evolution of the coal reservoir parameters hard to be conducted in the coalbed methane drainage project site, based on the physical simulation technology, real coal samples were applied to establish a similar physical model to experience and study the dynamic response feature meth od of the coal reservoir parameters during the coalbed methane drainage process.An independent research and developed physical simulation experiment system of th e coalbed methane drainage was applied to the physical simulation experiment of the coalbed methane drainage in a single seam under a 3D stress condition. The dyn amic evolution laws of the coal reservoir gas drainage flow, gas pressure, flow field, temperature and other parameters were obtained preliminarily. The gas drainage flo W was sharply increased in the initial gas drainage period and then was steadily decreased. The gas pressure with a distance more closed to the borehole would be dec reased more rapidly. The velocity of the gas flow closed to the borehole was high. At the initial gas drainage period, the temperature variation of the coal reservoir was small and in the late drainage period, with the desorption of the absorption gas, the temperature variation would be steadily increased. The study results could provide t he basic parameters and theoretical basis to the design of the numerical simulation and the coalbed methane drainage project.