Abstract: At present, the research on productivity of fractured vertical wells at home and abroad is mainly based on the existing seepage model, and the approximate solution is adopted to solve the productivity model. However, the accuracy of the productivity model has certain limitations. In order to correct the productivity equation of fractured vertical well and improve the prediction accuracy of production capacity, based on the previous research, a new productivity model with considering the factors such as fracture, heterogeneity and reservoir shooting degree is obtained from the most basic three-dimensional seepage equation. What's more, the model demonstration and sensitivity analysis are carried out for the fractured straight well productivity equation. The results show that in the early stage of the oil well production, productivity is mainly affected by the length of fractures and the degree of shot blasting, and the optimal fracture length and reasonable degree of reservoir blasting exist. In the middle and late stages of the oil well production, the productivity is mainly affected by fracture orientation, reservoir anisotropy and boundary condition. In the late stage of oil well production, productivity is mainly affected by reservoir width. This method can optimize the hydraulic fracturing parameters and guide the design of fracturing process. It can help to predict and analyze productivity.

Key words: Partially penetrating, Productivity analysis, Fractured vertical well, Fluid seepage, Tight sandstone reservoir

摘要： 目前国内外针对压裂直井产能的研究主要是建立在已有的渗流模型上,并且求解产能模型的方法采用了近似的处理方法,产能模型的精度具有一定的局限性。为修正压裂直井产能方程,提高产能预测精度,在前人研究的基础上,从最基本的三维渗流方程出发,考虑裂缝、非均质性和储层射开程度等因素,推导出适合致密砂岩油藏部分射开压裂直井产能方程,并进行了模型论证和敏感性分析。结果表明,油井生产早期,主要受裂缝长度、储层射开程度的影响,并且存在最优裂缝长度和合理储层射开程度;油井生产中后期,主要受裂缝方位、储层各向异性和边界条件的影响;油井生产后期,主要受油藏宽度的影响。该方法可以优化水力压裂参数,指导压裂工艺设计,有助于产能预测和分析。

关键词: 部分射开, 产能分析, 压裂直井, 流体渗流, 致密砂岩油藏