In this work exergetical performance analysis is carried out based on the second law of thermodynamics for organic flash cycle(OFC) using a two-phase expander instead of throttle expansion in order to recover efficien...In this work exergetical performance analysis is carried out based on the second law of thermodynamics for organic flash cycle(OFC) using a two-phase expander instead of throttle expansion in order to recover efficiently finite thermal reservoirs.The exergy destructions(anergies) at various components of the system are theoretically investigated as well as the exergy efficiency.Results show that the anergy of heat exchanger or two-phase expander decreases while the anergy of throttle valve increases with increasing flash temperature,and the exergy efficiency has an optimum value with respect to the flash temperature.Under the optimal conditions with respect to the flash temperature,exergy efficiency increases with the heating temperature and the component having the largest exergy destruction varies with the flash temperature or heating temperature.展开更多
A service life model of NAND flash and threshold voltage shift process is proposed to calculate the service life and endurance.The relationships among achievable program/erase(P/E) cycles,recovery time,bad block rate ...A service life model of NAND flash and threshold voltage shift process is proposed to calculate the service life and endurance.The relationships among achievable program/erase(P/E) cycles,recovery time,bad block rate and storage time are analyzed.The achievable endurance and service life of a NAND flash are evaluated based on a flash cell degradation and recovery model by varying recovery time,badblock rate,and storage time.It is proposed to improve the service lifetime of solid state disk by both relaxing the bad block rate limitation and retention time while extending the recovery time.The results indicate that endurance can be improved by 17 times if the storage time guarantee is reduced from 10 a to 1 a with 105 s recovery time inserted between cycles.展开更多
基金supported by Research Fund,Kumoh National Institute of Technology
文摘In this work exergetical performance analysis is carried out based on the second law of thermodynamics for organic flash cycle(OFC) using a two-phase expander instead of throttle expansion in order to recover efficiently finite thermal reservoirs.The exergy destructions(anergies) at various components of the system are theoretically investigated as well as the exergy efficiency.Results show that the anergy of heat exchanger or two-phase expander decreases while the anergy of throttle valve increases with increasing flash temperature,and the exergy efficiency has an optimum value with respect to the flash temperature.Under the optimal conditions with respect to the flash temperature,exergy efficiency increases with the heating temperature and the component having the largest exergy destruction varies with the flash temperature or heating temperature.
基金Project(61171017)supported by the National Natural Science Foundation of China
文摘A service life model of NAND flash and threshold voltage shift process is proposed to calculate the service life and endurance.The relationships among achievable program/erase(P/E) cycles,recovery time,bad block rate and storage time are analyzed.The achievable endurance and service life of a NAND flash are evaluated based on a flash cell degradation and recovery model by varying recovery time,badblock rate,and storage time.It is proposed to improve the service lifetime of solid state disk by both relaxing the bad block rate limitation and retention time while extending the recovery time.The results indicate that endurance can be improved by 17 times if the storage time guarantee is reduced from 10 a to 1 a with 105 s recovery time inserted between cycles.
