稠油油藏污染井产能模型及压裂增产模型研究

对稠油油藏压裂的研究主要集中在施工方法和技术上，产能预测仍然使用达西流模型。笔者基于稠油的非牛顿特性，考虑流体的启动压力梯度，推导出了稠油储层污染前后的垂直井产能预测模型，以及污染井压裂前后的产能模型。分析了非牛顿流体流变特性参数对产能模型的影响，启动压力梯度越大，非牛顿性越强，影响就越明显。计算表明，无论是稠油油藏还是普通油藏，压裂增产是很明显的，但经验公式增产更明显，这说明了对稠油油藏非牛顿因素的影响是存在的。稠油油藏污染井压裂增产模型为稠油油藏的污染井压裂提供了理论依据。

Modeling Productivities and Fracturing Enhancement of Contaminated Wells in Heavy-Oil Reservoirs

Studies of fracturing heavy oil reservoirs mainly focus on the operational techniques. Productivity predictions still employ the Darcy law now. Accounting for non-Newton rheology of heavy oil and the startup pressure gradient of fluids, a model for predicting productivities of a vertical well is derived. One model to describe the productivity of a contaminated well before and after fracturing operations is developed also. Furthermore, effects of rheological variables of non-Newton fluids on productivity models are analyzed, the bigger the start-up pressure, the stronger the non-Newtonian characteristics, the more evident the effects. Calculation results show that enhancement by fracturing is obvious, regardless of the heavy oil or the normal reservoir, especially according to rules of thumbs, which also indicates that effects of the non-Newton factors do exist. The model provides theory bases for fracturing contaminated wells in heavy oil reservoirs.