As an unconventional energy, coalbed methane (CBM) mainly exists in coal bed with adsorption, whose productivity is different\nfromconventional gas reservoir. This paper explains the wellbore pressure drop, surface pipeline network simulation, and reservoir\ncalculation model of CBM. A coupled surface/wellbore/reservoir calculation architecture was presented, to coordinate the gas\nproduction in each calculation period until the balance of surface/wellbore/reservoir. This coupled calculation method was applied\nto a CBM field for predicting production. The daily gas production increased year by year at the first time and then decreased\ngradually after several years, while the daily water production was reduced all the time with the successive decline of the formation\npressure. The production of gas and water in each well is almost the same when the structure is a star.When system structure is a\ndendritic surface system, the daily gas production ranked highest at the well which is the nearest to the surface system collection\npoint and lowest at the well which is the farthest to the surface system collection point. This coupled calculation method could be\nused to predict the water production, gas production, and formation pressure of a CBM field during a period of time.
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