Numerical simulation of two-phase flow in fractured karst reservoirs is still a challenging issue.The triple-porosity model is the major approach up to now.However,the triple-continuum assumption in this model is unac...Numerical simulation of two-phase flow in fractured karst reservoirs is still a challenging issue.The triple-porosity model is the major approach up to now.However,the triple-continuum assumption in this model is unacceptable for many cases.In the present work,an efficient numerical model has been developed for immiscible two-phase flowin fractured karst reservoirs based on the idea of equivalent continuum representation.First,based on the discrete fracture-vug model and homogenization theory,the effective absolute permeability tensors for each grid blocks are calculated.And then an analytical procedure to obtain a pseudo relative permeability curves for a grid block containing fractures and cavities has been successfully implemented.Next,a full-tensor simulator has been designed based on a hybrid numerical method(combining mixed finite element method and finite volume method).A simple fracture system has been used to demonstrate the validity of our method.At last,we have used the fracture and cavity statistics data fromTAHE outcrops in west China,effective permeability values and other parameters from our code,and an equivalent continuum simulator to calculate the water flooding profiles for more realistic systems.展开更多
针对航空超导全张量系统中高精度的磁场测量需求以及应用特点,采用一种新型频率测量方法可以更精确的测量光泵频率,从而可以更为精确的测量磁场。文中介绍了利用GPS授时信号作为闸门时间来进行频率测量的方法,并重点阐述了其设计方法;...针对航空超导全张量系统中高精度的磁场测量需求以及应用特点,采用一种新型频率测量方法可以更精确的测量光泵频率,从而可以更为精确的测量磁场。文中介绍了利用GPS授时信号作为闸门时间来进行频率测量的方法,并重点阐述了其设计方法;然后给出了该方法在50～300 k Hz的测量结果,试验表明该方法明显优于普通晶振提供闸门时间的频率测量方法,且在该频率段内最大误差小于0.02 Hz,同时验证了该方法达到实用要求且解决了航空超导全张量系统中使用晶振造成的电磁兼容问题及系统小型化问题。展开更多
本研究联合使用观测震相到时和波形互相关数据,采用双差法对2011年6月20日与8月9日发生在云南腾冲的5.2级双震及其余震序列进行重定位,并采用gCAP(generalized Cut and Paste)方法反演了该双震全矩张量解.结果显示,双震震中位于龙川江...本研究联合使用观测震相到时和波形互相关数据,采用双差法对2011年6月20日与8月9日发生在云南腾冲的5.2级双震及其余震序列进行重定位,并采用gCAP(generalized Cut and Paste)方法反演了该双震全矩张量解.结果显示,双震震中位于龙川江断裂的西侧,余震序列在深度上为一个倾斜的柱状体,且倾向腾冲火山区;6月20日和8月9日5.2级地震均表现为体积缩小的闭合型破裂,包含有显著的非双力偶成分,但后者包含的非双力偶成分相对明显减小.这些结果表明,云南腾冲5.2级双震及余震活动可能与火山下方的地壳岩浆作用密切相关,龙川江断裂为热物质向上运移提供了通道,而双震型地震的发生可能与首次地震的破裂体积缩小挤出的流体作用于断裂密切相关.展开更多
基金supported by the National Basic Research Program of China(“973”Program)(Grant No.2011CB201004)the ImportantNational Science and Technology Project of China(Grant No.2011ZX05014-005-003HZ)+2 种基金the National Natural Science Foundation of China(Grant No.11102237)the Introducing Talents of Discipline to Universities of China(Grant No.B08028)the Fundamental Research Funds for the Central Universities(Grant No.27R1102065A).
文摘Numerical simulation of two-phase flow in fractured karst reservoirs is still a challenging issue.The triple-porosity model is the major approach up to now.However,the triple-continuum assumption in this model is unacceptable for many cases.In the present work,an efficient numerical model has been developed for immiscible two-phase flowin fractured karst reservoirs based on the idea of equivalent continuum representation.First,based on the discrete fracture-vug model and homogenization theory,the effective absolute permeability tensors for each grid blocks are calculated.And then an analytical procedure to obtain a pseudo relative permeability curves for a grid block containing fractures and cavities has been successfully implemented.Next,a full-tensor simulator has been designed based on a hybrid numerical method(combining mixed finite element method and finite volume method).A simple fracture system has been used to demonstrate the validity of our method.At last,we have used the fracture and cavity statistics data fromTAHE outcrops in west China,effective permeability values and other parameters from our code,and an equivalent continuum simulator to calculate the water flooding profiles for more realistic systems.
文摘针对航空超导全张量系统中高精度的磁场测量需求以及应用特点,采用一种新型频率测量方法可以更精确的测量光泵频率,从而可以更为精确的测量磁场。文中介绍了利用GPS授时信号作为闸门时间来进行频率测量的方法,并重点阐述了其设计方法;然后给出了该方法在50～300 k Hz的测量结果,试验表明该方法明显优于普通晶振提供闸门时间的频率测量方法,且在该频率段内最大误差小于0.02 Hz,同时验证了该方法达到实用要求且解决了航空超导全张量系统中使用晶振造成的电磁兼容问题及系统小型化问题。
文摘本研究联合使用观测震相到时和波形互相关数据,采用双差法对2011年6月20日与8月9日发生在云南腾冲的5.2级双震及其余震序列进行重定位,并采用gCAP(generalized Cut and Paste)方法反演了该双震全矩张量解.结果显示,双震震中位于龙川江断裂的西侧,余震序列在深度上为一个倾斜的柱状体,且倾向腾冲火山区;6月20日和8月9日5.2级地震均表现为体积缩小的闭合型破裂,包含有显著的非双力偶成分,但后者包含的非双力偶成分相对明显减小.这些结果表明,云南腾冲5.2级双震及余震活动可能与火山下方的地壳岩浆作用密切相关,龙川江断裂为热物质向上运移提供了通道,而双震型地震的发生可能与首次地震的破裂体积缩小挤出的流体作用于断裂密切相关.
