一种微管中启动压力梯度测量方法
A GLOBAL-ORIENTED METHOD TO MEASURE THE THRESHOLD PRESSURE GRADIENT IN MICRO-CHANNELS
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摘要: 为了更加准确地测量低渗透多孔介质中液体流动的启动压力梯度,本文设计了一种在微管中测量启动压力梯度的方法:将静态法和稳态流动实验相结合,研究微管内的去离子水从静态到流动状态整体的压力反应. 实验结果表明:由稳态流动实验得到微管启动压力梯度,是静态法所得启动压力梯度值的14.5倍,说明在以往通过动态实验值所推得启动压力梯度数值过大. 这可以解释为在油藏工程中,实验室测得的启动压力梯度往往过大,无法向现场推广的原因. 研究表明:可以将该方法用于低渗透岩心的启动压力梯度测量实验中,更加准确的获得低渗透油藏的启动压力梯度值. 本文的研究不仅证明了微米尺度下启动压力梯度的存在,而且给出了更加准确测量启动压力梯度的方法.Abstract: A global oriented method of measuring of the threshold pressure gradient (TPG) in micro-channels was studied in this paper, in order to more accurately measure the TPG in the low permeability porous media. The method includes the static measurement and the steady flow experiments, and can be defined as the global-oriented method to measure the threshold pressure gradient, which can be used to analyze the pressure responses when the deionized water changes from the static state to the steady flow state in micro-channels. The experiments indicate that the threshold pressure gradient in the steady flow experiments is 14.5 times of that obtained by the static method, which shows that the previously published experimental values are too large, and are difficult to be used in the oil development. The results show that the global-oriented method of measuring the TPG can be applied for low permeability cores to obtain more precise parameters, and the TPG is verified when the liquid flows in micro-channels.