适于蒸汽辅助重力泄油开发的网格粗化技术

The Grid Upscaling Technology for Development of the Ultra-Heavy Oil Reservoir by Dual Horizontal Well SAGD Process

风城油田超稠油油藏蒸汽辅助重力泄油(SAGD)开发技术已逐步完善,但油藏工程研究环节仍面临常规网格粗化后信息损失量大的问题,尤其是对井轨迹偏移考虑不充分和薄隔夹层信息丢失,导致数值模拟结果精度不高,影响现场操作政策的制定,制约着SAGD的稳产高产。依据SAGD生产影响因素筛选关键信息,分析网格粗化算法、网格边界、网格尺寸对数值模拟的影响;利用Petrel软件进行网格粗化,对粗化模型进行验证;针对关键部分的信息缺失,借助数值模拟软件CMG的局部网格加密与网格属性回归来修正粗化模型,精细还原薄夹层。以此方法建立的油藏数值模型,在保障精度的同时提升了计算速度。以模型验证为控制手段,三维控制网格与二元叠合属性回归相结合的模型粗化技术,为精细地质模型与油藏数值模拟成功接口奠定了基础。

The development technology for ultra-heavy oil reservoir in Fengcheng oilfield in Junggar basin by dual horizontal well SAGD （steam assisted gravity drainage） process has been gradually perfected nowadays, but there were such obvious issues in the reservoir engineering study as much information loss of the regular upscaling, especially, the inadequate consideration of well trajectory deviation and the loss of thin interlayer information resulted in the resulting accuracy of numerical simulation to be not high, impacting the field operating policy to generate and restricting the stable and high production by this process. According to factors affecting SAGD production to screen key information, this paper analyzed the influence of the grid apscaling algorithm, the grid boundary and the grid size on the numerical simulation, verified the upsealing model using Petrel software for upscaling, and corrected the upsealing model in view of the loss at the key part information and by means of CMG software＇ s local grid refinement and grid attribute regression in order to reappear the original thin interlayers. This numerical simulation model developed by these approaches can ensure the resulting accuracy and improve the calculation speed. It is concluded that such a upscaling technology by model verification as a grid control means and 3D grid combination with binary composite attribute regression will lay the foundation for successful interface between the fine geologic modeling and the reservoir numerical simulation.