基于代数重构思想,发展了一种新的双界面函数重构方法,并采用双正弦函数构造了双正弦界面重构方法(double sine interface capturing,DSINC).为验证不同界面函数对界面捕捉效果的影响,用数值方法求解了可压缩五方程模型,其中对流项的离...基于代数重构思想,发展了一种新的双界面函数重构方法,并采用双正弦函数构造了双正弦界面重构方法(double sine interface capturing,DSINC).为验证不同界面函数对界面捕捉效果的影响,用数值方法求解了可压缩五方程模型,其中对流项的离散采用五阶WENO(weighted essentially non-oscillatory method)格式,时间积分采用三阶Runge--Kutta方法,通量计算分别考虑了HLL和HLLC方法,而状态方程采用Mie-Gr¨uneisen状态方程.在数值计算中,在界面附近,采用DSINC来获得体积分数的重构,而在远离界面的区域采用WENO格式来获得高阶插值状态.相比采用单界面函数的方法,如双曲正切界面重构方法(tangent of hyperbola for interface capturing,THINC),DSINC方法同样具有界面重构算法简单,在程序中添加方便等特点,两者区别在于,DSINC方法在重构过程中未知函数更易于求解,而无需求解复杂的非线性超越方程,这就使其具有易于向多维扩展的能力.一些典型的两相流动问题,如圆形水柱对流问题,两相三波点问题和激波-界面不稳定性问题等被用作不同界面函数对界面捕捉效果的影响对比.对比分析发现,DSINC与THINC在界面捕捉效果上大致保持一致,并在计算中表现出了较好的稳定性.双界面函数重构思想可以为多相流动界面的代数重构提供了一种新的思路.展开更多
In this paper, the generalized ranch function method is extended to （2＋1）-dimensianal canonical generalized KP （CGKP） equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit ...In this paper, the generalized ranch function method is extended to （2＋1）-dimensianal canonical generalized KP （CGKP） equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the （2＋1）-dimensional OGKP equation with variable coetffcients.展开更多
In this paper, a new extended complex tanh-function method is presented for constructing traveling wave, non-traveling wave, and coefficient functions＇ soliton-like solutions of nonlinear equations. This method is mo...In this paper, a new extended complex tanh-function method is presented for constructing traveling wave, non-traveling wave, and coefficient functions＇ soliton-like solutions of nonlinear equations. This method is more powerful than the complex tanh-function method [Chaos, Solitons and Fractals 20 （2004） 1037]. Abundant new solutions o[ （2q-1）-dimensional Hirota equation are obtained by using this method and symbolic computation system Maple.展开更多
This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He＇s semi-inverse meth...This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He＇s semi-inverse method （He＇s variational method）. Various traveling wave solutions are obtained, revealing an intrinsic relationship among the amplitude, frequency, and wave speed.展开更多
Using the modified extended tanh-function method,explicit and exact traveling wave solutions for the(2+1)-dimensional higher-order Broer-Kaup(HBK)system,comprising new soliton-like and period-form solutions,are obtained.
文摘基于代数重构思想,发展了一种新的双界面函数重构方法,并采用双正弦函数构造了双正弦界面重构方法(double sine interface capturing,DSINC).为验证不同界面函数对界面捕捉效果的影响,用数值方法求解了可压缩五方程模型,其中对流项的离散采用五阶WENO(weighted essentially non-oscillatory method)格式,时间积分采用三阶Runge--Kutta方法,通量计算分别考虑了HLL和HLLC方法,而状态方程采用Mie-Gr¨uneisen状态方程.在数值计算中,在界面附近,采用DSINC来获得体积分数的重构,而在远离界面的区域采用WENO格式来获得高阶插值状态.相比采用单界面函数的方法,如双曲正切界面重构方法(tangent of hyperbola for interface capturing,THINC),DSINC方法同样具有界面重构算法简单,在程序中添加方便等特点,两者区别在于,DSINC方法在重构过程中未知函数更易于求解,而无需求解复杂的非线性超越方程,这就使其具有易于向多维扩展的能力.一些典型的两相流动问题,如圆形水柱对流问题,两相三波点问题和激波-界面不稳定性问题等被用作不同界面函数对界面捕捉效果的影响对比.对比分析发现,DSINC与THINC在界面捕捉效果上大致保持一致,并在计算中表现出了较好的稳定性.双界面函数重构思想可以为多相流动界面的代数重构提供了一种新的思路.
基金Scientific Research Program Funded by Shaanxi Provincial Education Department(No.2013JK0572,ZK0953)Natural Science Basic Research Plan in Shaanxi Province of China(No.2014JM1027)
基金The project supported by the Natural Science Foundation of Shandong Province under Grant Nos. 2004zx16 and Q2005A01
文摘In this paper, the generalized ranch function method is extended to （2＋1）-dimensianal canonical generalized KP （CGKP） equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the （2＋1）-dimensional OGKP equation with variable coetffcients.
基金The project supported by National Natural Science Foundation of China and the Natural Science Foundation of Shandong Province of China
文摘In this paper, a new extended complex tanh-function method is presented for constructing traveling wave, non-traveling wave, and coefficient functions＇ soliton-like solutions of nonlinear equations. This method is more powerful than the complex tanh-function method [Chaos, Solitons and Fractals 20 （2004） 1037]. Abundant new solutions o[ （2q-1）-dimensional Hirota equation are obtained by using this method and symbolic computation system Maple.
文摘This paper studies the Generalized Bretherton equation using trigonometric function method including the sech-function method, the sine-cosine function method, and the tanh-function method, and He＇s semi-inverse method （He＇s variational method）. Various traveling wave solutions are obtained, revealing an intrinsic relationship among the amplitude, frequency, and wave speed.
文摘Using the modified extended tanh-function method,explicit and exact traveling wave solutions for the(2+1)-dimensional higher-order Broer-Kaup(HBK)system,comprising new soliton-like and period-form solutions,are obtained.
