Evaluation Of Single Well Productivity Of Carbonate Fractured Gas Reservoir With Bottom Water

The demand for oil and natural gas resources is increasing with the development of world industry.The study of single well productivity model of carbonate fractured gas reservoirs can help the management team to understand the productivity of gas wells and allocate the rational production properly.On the basis of analysis of geological and development characteristics of carbonate gas reservoirs with bottom water,three productivity analysis mathematical models with single medium model,dual-medium single-permeability model and dual-media dualpermeability model are established.The analytical solution of the models is obtained by Laplace transformation.The model is validated by an example,compared with CMG fitting results.Four theoretical models of single well of gas reservoir are establishes to study the effects of reservoir stress sensitivity,non-Darcy fluid,fracture elastic storage ratio,channeling coefficient,matrix-fracture permeability ratio,water body size and water invasion mode on the production characteristics of different models.According to the complex water invasion characteristics,the gas wells in carbonate fractured gas reservoirs with bottom water are divided into four categories and their reasonable production allocation ratios are studied.The allocation ratio results show that the type ? wells without fracture and bottom water is suitable for 1/7,the type ? with bottom water and without fractures is suitable for 1/10,the type ? with fractures and without the bottom water is suitable for 1/9,and the type ? with both fractures and bottom water is suitable for 1/12.