水泥浆流变性对水平井固井顶替界面的影响——基于天河一号大规模集群计算平台的数值模拟

水平封固段的固井顶替效果是影响水平井固井质量的关键问题，套管居中度与水泥浆流变性是影响水平段固井顶替效果的重要参数。基于国家超级计算中心天河一号大规模集群计算平台，采用Fluent软件对300 m长水平段偏心环空进行1 000 s的固井顶替数值模拟，研究水泥浆流变性对固井顶替界面的影响规律。研究结果表明:在低居中度（居中度≤50.0%）条件下，水泥浆流性指数n对顶替的影响可以忽略；在中等居中度（50.0% < 居中度 < 85.0%）条件下，提高水泥浆n值可以大幅改善环空宽边隔离液滞留，降低水泥浆n值可以改善环空窄边隔离液滞留，设计时需要综合考虑水泥浆n值；在高居中度（85.0%≤居中度 < 100%）与理想居中度（居中度100%）条件下，设计水泥浆n值时要避免出现其值过小的情况，从而避免在环空出现水泥浆分层窜流现象。研究结果对固井顶替施工设计具有重要指导作用。

Effect of rheological property of slurry on cementing displacement interface of horizontal well: the numerical simulation based on large-scale cluster computing platform Tianhe-1

Cementing displacement effect of horizontal cementing section is the key to cementing quality of horizontal wells.And the centralized degree of casing and the rheological property of slurry are important parameters impacting cementing displacement effect of horizontal section.In this paper, the cementing displacement in the eccentric annulus of horizontal section (300 m long) was numerically simulated for 1 000 s by using Fluent software on the large-scale cluster computing platform Tianhe-1 of National Supercomputing Center, to investigate the influential laws of rheological property of slurry on cementing displacement interface.It is indicated that the effect of slurry flow index (n) on displacement is negligible when the centralized degree is low (≤50.0%).When the centralized degree is moderate (50.0% < centralized degree < 85.0%), the retention of spacer fluid at the wide (narrow) side can be improved significantlyby increasing (decreasing) slurry n, so it is necessary to take slurry n into consideration comprehensively during the design.In the case of high centralized degree (85.0%≤centralized degree < 100%) and ideal centralized degree (100%), it is necessary to prevent slurry n from being too low during the design, so as to avoid slurry from stratified channeling in annulus.The research results can be used as the instruction for the design of cementing displacement operation.