Cylindrical effects in weakly nonlinear Rayleigh Taylor instability  

作　　者：刘万海 马文芳 王绪林 

机构地区：[1]Research Center of Computational Physics,Mianyang Normal University [2]HEDPS and CAPT,Peking University

出　　处：《Chinese Physics B》2015年第1期388-393,共6页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant No.10835003);the National Natural Science Foundation of China(Grant No.11274026);the Scientific Research Foundation of Mianyang Normal University,China(Grant Nos.QD2014A009 and 2014A02);the National HighTech ICF Committee

摘　　要：The classical Rayleigh–Taylor instability（RTI） at the interface between two variable density fluids in the cylindrical geometry is explicitly investigated by the formal perturbation method up to the second order. Two styles of RTI, convergent（i.e., gravity pointing inward） and divergent（i.e., gravity pointing outwards） configurations, compared with RTI in Cartesian geometry, are taken into account. Our explicit results show that the interface function in the cylindrical geometry consists of two parts： oscillatory part similar to the result of the Cartesian geometry, and non-oscillatory one contributing nothing to the result of the Cartesian geometry. The velocity resulting only from the non-oscillatory term is followed with interest in this paper. It is found that both the convergent and the divergent configurations have the same zeroth-order velocity, whose magnitude increases with the Atwood number, while decreases with the initial radius of the interface or mode number. The occurrence of non-oscillation terms is an essential character of the RTI in the cylindrical geometry different from Cartesian one.The classical Rayleigh–Taylor instability（RTI） at the interface between two variable density fluids in the cylindrical geometry is explicitly investigated by the formal perturbation method up to the second order. Two styles of RTI, convergent（i.e., gravity pointing inward） and divergent（i.e., gravity pointing outwards） configurations, compared with RTI in Cartesian geometry, are taken into account. Our explicit results show that the interface function in the cylindrical geometry consists of two parts： oscillatory part similar to the result of the Cartesian geometry, and non-oscillatory one contributing nothing to the result of the Cartesian geometry. The velocity resulting only from the non-oscillatory term is followed with interest in this paper. It is found that both the convergent and the divergent configurations have the same zeroth-order velocity, whose magnitude increases with the Atwood number, while decreases with the initial radius of the interface or mode number. The occurrence of non-oscillation terms is an essential character of the RTI in the cylindrical geometry different from Cartesian one.

关 键 词：cylindrical effect Rayleigh–Taylor instability variable density fluid 

分 类 号：O411[理学—理论物理]