凝析气液复杂渗流数学模型

为真实反映凝析气藏相变过程中流体的流动情况，需要考虑气、液相变作用及流-固热耦合对凝析气藏渗流规律的影响。引入相变产生的毛管力、界面阻力及非达西因子，建立表征凝析气藏多相高速流动相变特征的渗流方程，同时考虑气化潜热及流-固热耦合，推导出流-固热耦合能量方程，结合凝析气藏相变特征的传输方程，对速度场、温度场进行量化计算，从而合理描述流体渗流的特性和过程。利用该模型进行凝析气井复杂渗流规律研究，结果认为：凝析气相变对凝析气渗流的影响显著；流体与岩石颗粒温度在相变区都是先升后降，最终低于气藏原始温度，但岩石颗粒温度变化有滞后趋势；模型考虑界面张力、毛管力时预测的凝析气产能低，凝析油产能高。

Mathematical model for condensate gas and fluid flow

The effects of phase change between gas and fluid and fluid-solid heat coupling on the flow in condensate reservoir should be taken into consideration to disclose the fluid flow performance during phase change of the reservoir. By introducing the capillary pressure, interracial resistance, and non-Darcy flow effect caused by phase change, a mathematical model for high velocity multiphase flow in condensate reservoir is set up. Integrating vaporization latent heat and fluid-solid heat coupling, the fluid-solid heat coupling equation is derived. The velocity field and temperature field is calculated with the transmission equation of phase change, the flow performance and process could be described, suggesting that the phase change action has great effect on the flow mechanism of condensate gas. The temperature of the fluid and rock rose and then dropped to below original reservoir temperature, but the rock temperature change displayed a hysteresis. With the interracial force and capillary pressure accounted, the model predicted a lower gas and higher condensate yield.