摘要
随着地层压力的下降,与指数式产能方程流动系数密切相关的参数,如天然气偏差系数、天然气粘度、气层渗透率、有效厚度等都是变化的。气层渗透率、有效厚度的变化甚微,相比之下可以忽略不计;而天然气偏差系数和粘度的变化却不容忽视,两者之乘积不断变小,由此引起指数式产能方程流动系数不断增大。通过分析,给出了指数式产能方程流动系数随天然气偏差系数和粘度对应变化的关系式。当已知气井某一时刻的指数式产能方程后,便可确定任意地层压力下的气井产能,从而更准确地指导气井开采,避免重复试井工作。
With a drop in formation pressure, the parameters which closely related to the flow coefficient of the exponential deliverability equation are varied, such as gas deviation factor, gas viscosity, reservoir permeability, effective thickness and so on. The variations of reservoir permeability and effective thickness can be overlooked because of their minimal variations. But the variations of gas deviation factor and gas viscosity should not be ignored, whose product gradually decreases which results in the flow coefficient of the exponential deliverability equation escalating. By analysis, the relation equation is presented which the flow coefficient of the exponential deliverability equation is changing with variation of gas deviation factor and gas viscosity. When exponential deliverability equation is known at a certain moment in gas well, gas well deliverability can be identified under the arbitrary formation pressure to accurately guide the exploitation in gas wells and avoid repeating well testing.
出处
《油气井测试》
2008年第4期13-15,共3页
Well Testing
关键词
气井
地层压力
指数式
产能
无阻流量
偏差系数
粘度
gas well, formation pressure, exponential, deliverability, AOF, deviation factor, viscosity
