摘要
给出了一种模拟温度和压力动态的数学模型和它们之间的相互干扰以及小型压裂测试中压裂液压缩性的影响。关井前,利用数值解和PKN模型的近似解来计算裂缝几何参数;关井后,采用线弹性理论通过模拟压力计算裂缝宽度。模拟结果表明,小型压裂测试阶段的裂缝温度有显著的变化,比起不可压缩压裂液,可压缩流体的压力更高,下降速度更慢。如果流体是可压缩的,则通过Nolte压力降落分析方法计算的滤失系数偏小。此外研究还表明,采用关井阶段后期压力数据计算的滤失系数误差较小。
A kind of mathematic model to simulate temperature and pressure performance, interference between them and influence from compressibility of fracturing fluid testing in small type of fracture are presented. Numerical value solution and approximate solution of PKN model is used to calculate geometry parameter of the crack before well's closing, while, linear and elastic theory is utilized to calculate width of crack through simulating pressure. The simulating effect shows that crack temperature has obvious change at small scale fracture testing period. Comparing with uncompressible fracturing fluid, the higher of the pressure of compressible fluid, the much slow for the descent speed. If the fluid is compressible, the sieve coefficient computed by Nolte pressure fall down analysis method is much little. Farther, the study also indicates that the error of sieve coefficient calculated by later time of pressure data at well closing period is much small.
出处
《油气井测试》
2007年第1期8-10,共3页
Well Testing
关键词
温度
压力
压力降落
分析
数学模型
temperature, pressure, fall down of pressure, analysis, mathematic model
