The influence of thermo cycle times under variant loads and environment temperatures on the properties of Cu-16.4Zn-4Al (Re) SMA component was studied by thermostability experiments on Cu-16.4Zn-4Al SMA with the compo...The influence of thermo cycle times under variant loads and environment temperatures on the properties of Cu-16.4Zn-4Al (Re) SMA component was studied by thermostability experiments on Cu-16.4Zn-4Al SMA with the composition containing corium Re. Tangent rule was applied to determine the transformation temperature from displacement-temperature loop plot by computer in each thermal-cold cycle. The results is as follows the transformation temperature increases and shape memory property decrease with increasing load, which leads the action temperature of component to be abnormal, and the memory property decreases after overheating aging, and the memory property decreases with increasing cycle times, while the decreasing is not obvious and the recovery ratio is higher than 90% in one thousand times. It is due to the addition of corium Re which has the function of grain refinement. Therefore, it is necessary to avoid overloading and overheating in the application of such component. Thus, a kind of thermo valve that works at normal pressure and in the water as working substance was designed to replace complicate original electromechanical system.展开更多
Post shut‐in seismic events in enhanced geothermal systems(EGSs)occur predominantly at the outer rim of the co‐injection seismic cloud.The concept of postinjection fracture and fault closure near the injection well ...Post shut‐in seismic events in enhanced geothermal systems(EGSs)occur predominantly at the outer rim of the co‐injection seismic cloud.The concept of postinjection fracture and fault closure near the injection well has been proposed and validated as a mechanism for enhancing post shut‐in pressure diffusion that promotes seismic hazard.This phenomenon is primarily attributed to the poro‐elastic closure of fractures resulting from the reduction of wellbore pressure after injection termination.However,the thermal effects in EGSs,mainly including heat transfer and thermal stress,may not be trivial and their role in postinjection fault closure and pressure evolution needs to be explored.In this study,we performed numerical simulations to analyze the relative importance of poro‐elasticity,heat transfer,and thermo‐elasticity in promoting postinjection fault closure and pressure diffusion.The numerical model wasfirst validated against analytical solutions in terms offluid pressure diffusion and against heatedflow‐through experiments in terms of thermal processes.We then quantified and distinguished the contribution of each individual mechanism by comparing four different shut‐in scenarios simulated under different coupled conditions.Our results highlight the importance of poro‐elastic fault closure in promoting postinjection pressure buildup and seismicity,and suggest that heat transfer can further augment the fault closure‐induced pressure increase and thus potentially intensify the postinjection seismic hazard,with minimal contribution from thermo‐elasticity.展开更多
文摘The influence of thermo cycle times under variant loads and environment temperatures on the properties of Cu-16.4Zn-4Al (Re) SMA component was studied by thermostability experiments on Cu-16.4Zn-4Al SMA with the composition containing corium Re. Tangent rule was applied to determine the transformation temperature from displacement-temperature loop plot by computer in each thermal-cold cycle. The results is as follows the transformation temperature increases and shape memory property decrease with increasing load, which leads the action temperature of component to be abnormal, and the memory property decreases after overheating aging, and the memory property decreases with increasing cycle times, while the decreasing is not obvious and the recovery ratio is higher than 90% in one thousand times. It is due to the addition of corium Re which has the function of grain refinement. Therefore, it is necessary to avoid overloading and overheating in the application of such component. Thus, a kind of thermo valve that works at normal pressure and in the water as working substance was designed to replace complicate original electromechanical system.
文摘Post shut‐in seismic events in enhanced geothermal systems(EGSs)occur predominantly at the outer rim of the co‐injection seismic cloud.The concept of postinjection fracture and fault closure near the injection well has been proposed and validated as a mechanism for enhancing post shut‐in pressure diffusion that promotes seismic hazard.This phenomenon is primarily attributed to the poro‐elastic closure of fractures resulting from the reduction of wellbore pressure after injection termination.However,the thermal effects in EGSs,mainly including heat transfer and thermal stress,may not be trivial and their role in postinjection fault closure and pressure evolution needs to be explored.In this study,we performed numerical simulations to analyze the relative importance of poro‐elasticity,heat transfer,and thermo‐elasticity in promoting postinjection fault closure and pressure diffusion.The numerical model wasfirst validated against analytical solutions in terms offluid pressure diffusion and against heatedflow‐through experiments in terms of thermal processes.We then quantified and distinguished the contribution of each individual mechanism by comparing four different shut‐in scenarios simulated under different coupled conditions.Our results highlight the importance of poro‐elastic fault closure in promoting postinjection pressure buildup and seismicity,and suggest that heat transfer can further augment the fault closure‐induced pressure increase and thus potentially intensify the postinjection seismic hazard,with minimal contribution from thermo‐elasticity.
