Research On Numerical Simulation Application Of Coalbed Methane

Pinnate horizontal multilateral well and vertical well fracturing are efficient technology which can increase coalbed gas recovery rate. In this dissertation, the numerical simulation technique is used providing necessary theory basis and guidance scheme for the implement of these two technology. The main research as follows:1 , The software of Pinnate horizontal multilateral well is consummated. With a coalbed gas Pinnate horizontal multilateral well as an example, the productivity is forecasted. It is proved that the software is suitable for numerical simulation.2, The effect of increase and the stratum pressure is compared between the pinnate horizontal multilateral well and the vertical hydraulic fracturing well. The main lateral and side laterals extending widely in stratum makes the stratum pressure drow down rapidly and uniformly in controlled area, which facilitates the desorption and diffusion of adsorbed gas.3 , The effect of formation parameters and wellbore structures parameters on the gas production rate of pinnater horizontal multilateral well are analyzed. We gain the according of electing and evaluating good reservoir and the priciples on designing wellbore structure. The recovery effectiveness of multi-main lateral distributing uniformly is superior to single main lateral. There exists the optimal value of space between side laterals. The formation parameters are the prime factor which can effect the gas production.4, The geological model is developed which can effect the heterogeneous reservoir characteristic. The effect of heterogeneous on the gas production is analyzed. The method of...