水溶性ガス田の産出挙動シミュレーション

抄録

Two numerical models for predicting production behavior of the water-dissolved gas field are developed. One model is constructed for the ordinary type gas reservoir that is composed of sandstone layer and the other for the Mobara type gas reservoir that is composed of the alternation of sandstone and mudstone. These models consist of the mathematical description of the two-phase (water and methane gas) flow in a horizontal, twodimensional system. In particular, the description of the Mobara type model considers the gas excudation at the face of the mudstone layer.
These models are used to discuss the problem of interference between two production wells. The result shows that the well interference causes a decrease in production gaswater ratio in the ordinary type, but a remarkable increase in the Mobara type.
An application of the Mobara type model to the practical water-dissolved gas field has revealed that the calculated value of average production gas-water ratio of all the wells is in a general agreement with the measured value.