Owing to the particularity of a polyester fiber material,the polyester mooring undergoes large axial tensile deformation over long-term use.Large axial tensile deformation significantly impacts the dynamic response of...Owing to the particularity of a polyester fiber material,the polyester mooring undergoes large axial tensile deformation over long-term use.Large axial tensile deformation significantly impacts the dynamic response of the mooring system.In addition,the degrees of large axial tension caused by different elastic moduli are also different,and the force on the mooring line is also different.Therefore,it is of great significance to study the influence of elastic modulus on the dynamic results of the mooring systems under large axial tension.Conventional numerical software fails to consider the axial tension deformation of the mooring.Based on the theory of slender rods,this paper derives the formula for large axial tension using the method of overall coordinates and overall slope coordinates and provides the calculation programs.Considering a polyester mooring system as an example,the calculation program and numerical software are used to calculate and compare the static and dynamic analyses to verify the reliability of the calculation program.To make the force change of the mooring obvious,the elastic moduli of three different orders of magnitude are compared and analyzed,and the dynamic response results after large axial tension are compared.This study concludes that the change in the elastic modulus of the polyester mooring changes the result of the vertex tension by generating an axial tension.The smaller the elastic modulus,the larger the forced oscillation motion amplitude of the top point of the mooring line,the more obvious the axial tension phenomenon,and the smaller the force on the top of the polyester mooring.展开更多
An improved electromechanical model of the RF MEMS(radio frequency microelec- tromechanical systems)switches is introduced,in which the effects of intrinsic residual stress from fabrication processes,axial stress due ...An improved electromechanical model of the RF MEMS(radio frequency microelec- tromechanical systems)switches is introduced,in which the effects of intrinsic residual stress from fabrication processes,axial stress due to stretching of beam,and fringing field are taken into account. Four dimensionless numbers are derived from the governing equation of the developed model.A semi- analytical method is developed to calculate the behavior of the RF MEMS switches.Subsequently the influence of the material and geometry parameters on the behavior of the structure is analyzed and compared,and the corresponding analysis with the dimensionless numbers is conducted too.The quantitative relationship between the presented parameters and the critical pull-in voltage is obtained, and the relative importance of those parameters is given.展开更多
基金Supported by the Specialized Research Project for LS17-2 Semi-submersible Production Platform(LSZX-2020-HN-05-0405)the Engineering Development Program of Deepwater Semisubmersible Production Storage and Unloading Platform of China(SSBQ-2020-HN-02-04)。
文摘Owing to the particularity of a polyester fiber material,the polyester mooring undergoes large axial tensile deformation over long-term use.Large axial tensile deformation significantly impacts the dynamic response of the mooring system.In addition,the degrees of large axial tension caused by different elastic moduli are also different,and the force on the mooring line is also different.Therefore,it is of great significance to study the influence of elastic modulus on the dynamic results of the mooring systems under large axial tension.Conventional numerical software fails to consider the axial tension deformation of the mooring.Based on the theory of slender rods,this paper derives the formula for large axial tension using the method of overall coordinates and overall slope coordinates and provides the calculation programs.Considering a polyester mooring system as an example,the calculation program and numerical software are used to calculate and compare the static and dynamic analyses to verify the reliability of the calculation program.To make the force change of the mooring obvious,the elastic moduli of three different orders of magnitude are compared and analyzed,and the dynamic response results after large axial tension are compared.This study concludes that the change in the elastic modulus of the polyester mooring changes the result of the vertex tension by generating an axial tension.The smaller the elastic modulus,the larger the forced oscillation motion amplitude of the top point of the mooring line,the more obvious the axial tension phenomenon,and the smaller the force on the top of the polyester mooring.
基金The project supported by the National Natural Science Foundation of China,the Chinese Academy of Sciences,the RGC/NSFC Joint Research Scheme (N-HKUST 601/01)the Joint Laboratory of Microsystems
文摘An improved electromechanical model of the RF MEMS(radio frequency microelec- tromechanical systems)switches is introduced,in which the effects of intrinsic residual stress from fabrication processes,axial stress due to stretching of beam,and fringing field are taken into account. Four dimensionless numbers are derived from the governing equation of the developed model.A semi- analytical method is developed to calculate the behavior of the RF MEMS switches.Subsequently the influence of the material and geometry parameters on the behavior of the structure is analyzed and compared,and the corresponding analysis with the dimensionless numbers is conducted too.The quantitative relationship between the presented parameters and the critical pull-in voltage is obtained, and the relative importance of those parameters is given.
基金supported by the National Natural Science Foundation of China(52172223,52272230,and 51972223)the Young Elite Scientists Sponsorship Program by Tianjin(TJSQNTJ-202011)+3 种基金the National Key Research and Development Program of China(2021YFF0500600 and 2022YFB2404500)the National IndustryEducation Integration Platform of Energy Storagethe Haihe Laboratory of Sustainable Chemical Transformationsthe Fundamental Research Funds for the Central Universities。
