The influence of the slip mode on the microstructure evolution and compressive flow behavior at different strains in an extruded dilute Mg−0.5Bi−0.5Sn−0.5Mn alloy was analyzed through electron backscatter diffraction,...The influence of the slip mode on the microstructure evolution and compressive flow behavior at different strains in an extruded dilute Mg−0.5Bi−0.5Sn−0.5Mn alloy was analyzed through electron backscatter diffraction,X-ray diffraction,transmission electron microscopy,and hot compression tests.The results showed that at a low strain of 0.05,the basal,pyramidaland<c+a>slip modes were simultaneously activated.Nevertheless,at the middle stage of deformation(strain of 0.1,0.2 and 0.5),theslip mode was difficult to be activated and<c+a>slip mode became dominant.The deformation process between strains of 0.2 and 0.5 was primarily characterized by the softening effect resulting from the simultaneous occurrence of continuous dynamic recrystallization and discontinuous dynamic recrystallization.Ultimately,at strain of 0.8,a dynamic equilibrium was established,with the flow stress remaining constant due to the interplay between the dynamic softening brought about by discontinuous dynamic recrystallization and the work-hardening effect induced by the activation of the basalslip mode.展开更多
针对风电输出功率的随机性、波动性等特点,在计及风电功率波动和电池储能系统BESS(battery energy storage system)的荷电状态SOC(state of charge)等约束条件的基础上,提出一种基于变滑动平均滤波项数的风电功率波动平滑控制策略。该...针对风电输出功率的随机性、波动性等特点,在计及风电功率波动和电池储能系统BESS(battery energy storage system)的荷电状态SOC(state of charge)等约束条件的基础上,提出一种基于变滑动平均滤波项数的风电功率波动平滑控制策略。该方法根据风电功率波动和BESS的SOC值,对滑动平均滤波中的项数进行调节,进而调节输出功率的目标值,使BESS的SOC稳定在一定的范围内,避免了BESS的过充/放电,并且提高了系统输出功率平滑效果。仿真分析表明,本文方法在BESS的SOC稳定在限定范围的同时,20 min内风电功率波动率控制在10%内,20 min功率波动累加和比普通滑动平均滤波策略下减少了20.5%,有效提高了风电输出功率的平滑性。展开更多
Static and dynamic numerical simulations of high recording density disk drivers are presented in this paper. The shear thinning effect on the viscosity is taken into account in the lubricant rheological model. The per...Static and dynamic numerical simulations of high recording density disk drivers are presented in this paper. The shear thinning effect on the viscosity is taken into account in the lubricant rheological model. The perturbation theory and short bearing theory are employed to set up the static and dynamic lubrication model on the head disk interface. Close solutions are given for the pressure distribution, load capacity and the dynamic characteristics such as stiffness and damping coefficients, which provide a simple method to analyze the dynamic response of the slider supported by the ultra thin fluid film lubricated bearing. Based on the close solutions the static and dynamic responses of the IBM 3380 slider are simulated. Some interesting results are obtained for the analysis of the slider’s flying stability.展开更多
基金supported by the National Natural Science Foundation of China (No.51901153)Shanxi Scholarship Council of China (No.2019032)+2 种基金Natural Science Foundation of Shanxi Province,China (No.202103021224049)the Shanxi Zhejiang University New Materials and Chemical Research Institute Scientific Research Project,China (No.2022SX-TD025)the Open Project of Salt Lake Chemical Engineering Research Complex,Qinghai University,China (No.2023-DXSSKF-Z02)。
文摘The influence of the slip mode on the microstructure evolution and compressive flow behavior at different strains in an extruded dilute Mg−0.5Bi−0.5Sn−0.5Mn alloy was analyzed through electron backscatter diffraction,X-ray diffraction,transmission electron microscopy,and hot compression tests.The results showed that at a low strain of 0.05,the basal,pyramidaland<c+a>slip modes were simultaneously activated.Nevertheless,at the middle stage of deformation(strain of 0.1,0.2 and 0.5),theslip mode was difficult to be activated and<c+a>slip mode became dominant.The deformation process between strains of 0.2 and 0.5 was primarily characterized by the softening effect resulting from the simultaneous occurrence of continuous dynamic recrystallization and discontinuous dynamic recrystallization.Ultimately,at strain of 0.8,a dynamic equilibrium was established,with the flow stress remaining constant due to the interplay between the dynamic softening brought about by discontinuous dynamic recrystallization and the work-hardening effect induced by the activation of the basalslip mode.
文摘针对风电输出功率的随机性、波动性等特点,在计及风电功率波动和电池储能系统BESS(battery energy storage system)的荷电状态SOC(state of charge)等约束条件的基础上,提出一种基于变滑动平均滤波项数的风电功率波动平滑控制策略。该方法根据风电功率波动和BESS的SOC值,对滑动平均滤波中的项数进行调节,进而调节输出功率的目标值,使BESS的SOC稳定在一定的范围内,避免了BESS的过充/放电,并且提高了系统输出功率平滑效果。仿真分析表明,本文方法在BESS的SOC稳定在限定范围的同时,20 min内风电功率波动率控制在10%内,20 min功率波动累加和比普通滑动平均滤波策略下减少了20.5%,有效提高了风电输出功率的平滑性。
文摘Static and dynamic numerical simulations of high recording density disk drivers are presented in this paper. The shear thinning effect on the viscosity is taken into account in the lubricant rheological model. The perturbation theory and short bearing theory are employed to set up the static and dynamic lubrication model on the head disk interface. Close solutions are given for the pressure distribution, load capacity and the dynamic characteristics such as stiffness and damping coefficients, which provide a simple method to analyze the dynamic response of the slider supported by the ultra thin fluid film lubricated bearing. Based on the close solutions the static and dynamic responses of the IBM 3380 slider are simulated. Some interesting results are obtained for the analysis of the slider’s flying stability.
