A novel type curve is presented for oil recovery factor prediction suitable for gas flooding by innovatively introducing the equivalent water-gas cut to replace the water cut,comprehensively considering the impact of ...A novel type curve is presented for oil recovery factor prediction suitable for gas flooding by innovatively introducing the equivalent water-gas cut to replace the water cut,comprehensively considering the impact of three-phase flow(oil,gas,water),and deriving the theoretical equations of gas flooding type curve based on Tong’s type curve.The equivalent water-gas cut is the ratio of the cumulative underground volume of gas and water production to the total underground volume of produced fluids.Field production data and the numerical simulation results are used to demonstrate the feasibility of the new type curve and verify the accuracy of the prediction results with field cases.The new type curve is suitable for oil recovery factor prediction of both water flooding and gas flooding.When a reservoir has no gas injected or produced,the gas phase can be ignored and only the oil and water phases need to be considered,in this case,this gas flooding type curve returns to the Tong’s type curve,which can evaluate the oil recovery factor of water flooding.For reservoirs with equivalent water-gas cuts of 60%-80%,the regression method of the new type curve works well in predicting the oil recovery factor.For reservoirs with equivalent water-gas cuts higher than 80%,both the regression and assignment methods of the new type curve can accurately predict the oil recovery factor of gas flooding.展开更多
为实现吴忠市暴雨洪水管理模型(storm water management model,SWMM)的高效率定,分别采用修正的莫里斯(Morris)法和互信息法,分析了洪峰流量和径流系数的模拟结果对SWMM的7个相关产流参数的局部和全局敏感性.2种方法均识别出不透水面-...为实现吴忠市暴雨洪水管理模型(storm water management model,SWMM)的高效率定,分别采用修正的莫里斯(Morris)法和互信息法,分析了洪峰流量和径流系数的模拟结果对SWMM的7个相关产流参数的局部和全局敏感性.2种方法均识别出不透水面-曼宁系数(IMP-N)和不透水区洼地蓄水深度(IMP-DS)为SWMM的主要敏感参数.洪峰流量对IMP-N和IMP-DS最敏感,径流系数对IMP-DS最敏感;参数的敏感性随降雨强度的增大先增大后减小,洪峰流量对IMP-DS和IMP-N的敏感性分别在3和10 a的降雨重现期达到最大值,径流系数对IMP-DS和IMP-N的敏感性分别在2和3 a的降雨重现期达最大值;敏感参数间的协同作用随降雨强度增大而减弱.结果表明,吴忠市中心城区的易涝区应优先考虑增加地表粗糙度与洼地蓄水深度.本成果可为以高不透水率为特征的其他城市密集建成区的削峰减排提供参考.展开更多
基金Supported by the National Natural Science Foundation of China(51974268)the Sichuan Province Science and Technology Program(2019YJ0423)。
文摘A novel type curve is presented for oil recovery factor prediction suitable for gas flooding by innovatively introducing the equivalent water-gas cut to replace the water cut,comprehensively considering the impact of three-phase flow(oil,gas,water),and deriving the theoretical equations of gas flooding type curve based on Tong’s type curve.The equivalent water-gas cut is the ratio of the cumulative underground volume of gas and water production to the total underground volume of produced fluids.Field production data and the numerical simulation results are used to demonstrate the feasibility of the new type curve and verify the accuracy of the prediction results with field cases.The new type curve is suitable for oil recovery factor prediction of both water flooding and gas flooding.When a reservoir has no gas injected or produced,the gas phase can be ignored and only the oil and water phases need to be considered,in this case,this gas flooding type curve returns to the Tong’s type curve,which can evaluate the oil recovery factor of water flooding.For reservoirs with equivalent water-gas cuts of 60%-80%,the regression method of the new type curve works well in predicting the oil recovery factor.For reservoirs with equivalent water-gas cuts higher than 80%,both the regression and assignment methods of the new type curve can accurately predict the oil recovery factor of gas flooding.
