摘要
蒸汽驱开采具有明显的阶段性,目前蒸汽超覆程度评价方法针对的是整个蒸汽驱过程,而没有考虑蒸汽驱不同阶段不同蒸汽前缘下超覆程度的差异性。对注入蒸汽的受力和速度分析,利用垂向流量比和迭代算法得出不同蒸汽前缘下的蒸汽超覆程度评价方法。垂向流量比表征了注采井间区域蒸汽超覆的能力,流量比越大,蒸汽超覆能力越强,注采井间中间区域的超覆能力远大于近注采井20 m区域,蒸汽超覆程度随着蒸汽前缘的推进而越来越严重。对影响蒸汽超覆程度的因素敏感性进行分析得出,径向与垂向渗透率的比值越大,井距越小,注采强度越强,压力梯度越大,蒸汽超覆程度越弱。通过数值模拟对蒸汽腔形态和剩余油分布进行了研究,其结果与理论分析是吻合的。
Steam flooding shows obvious phased feature.Evaluation of steam override is conducted usually for the whole process of steam flooding without considering the differences in override degree at different steam flooding stages and steam fronts.Based on analysis of the force and velocity of injected steam,an evaluation method of steam override degree at different steam fronts has been obtained by using vertical flow ratio and iterative algorithm.Vertical flow ratio characterizes the ability of regional steam override between injector and producer.The greater the flow ratio is,the stronger the override ability is.Steam override in the middle of injector and producer is much greater than in the regions 20m around injector and producer.The degree of steam override becomes severe with the propagation of steam front.Sensitivity analysis on the factors affecting steam override degree has concluded that the greater the ratio of radial to vertical permeabilities,the smaller the well spacing,the stronger the injection-production intensity,and the higher the pressure gradient is,the lower the degree of steam override would be.The result of numerical simulation on steam chamber geometry and remaining oil distribution is consistent with the theoretical analysis in the paper.
出处
《特种油气藏》
CAS
CSCD
北大核心
2013年第2期79-83,155,共5页
Special Oil & Gas Reservoirs
基金
国家科技重大专项"西非深水典型油气田高效开发产能评价研究"(2008ZX05030-005-03)
关键词
蒸汽超覆
蒸汽前缘
垂向流量比
数值模拟
steam override
steam front
vertical flow ratio
numerical simulation