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991.
应用势流理论,采用递推函数方法推导出一个新形式的Bousinesq方程。通过对新方程的参数设置,可以讨论出Boussinesq方程发展趋势和不同的发展形式。对浅水波动的描述方程,Boussinesq方程的发展趋势为适用水深范围的拓展。拓展应用范围的大小则由其方程频散特征向Airy波频散解逼近程度来决定。而Bousineq方程又不同于Airy波,主要原因是Boussinesq方程中含有线性频散项,Airy波则只是长波首项近似,无线性频散项。其频散特征为精确的线性频散解。对实际水波传播而言,Airy波理论的局限性是不言而喻的。 相似文献
992.
RenWenmin(任文敏);HuangJianmin(黄剑敏);ChenWen(陈文)(ReceivedDec.25,1994;CommunicatedbyYangGuitong)APPROXIMATEFORMULASOFIMPACTFORCEFO... 相似文献
993.
Ming Ruisen 《Acta Mechanica Sinica》1996,12(3):251-262
Quasi-longitudinal waves are one type of structural waves, which are important at high frequencies. This paper studies the
estimate theory and measurement technique of quasi-longitudinal waves, analyzes the bias error due to the effect of bending
waves. In a two-dimensional quasi-longitudinal wave field, the intensity vector is the sum of the effective intensity vector
and the intensity variation vector. Its axial component is proportional to two imaginary parts of cross spectral densities
and in the measurement, it is measured by a pair of two-transducer arrays. In a onedimensional quasi-longitudinal wave field,
the intensity variation is zero, the intensity is proportional to only one imaginary part of a cross spectral density and
it can be measured using a two-transducer array. If bending and quasi-longitudinal waves coexist and the contribution from
bending waves cannot be eliminated or reduced to a certain extent, the measured quasi-longitudinal wave intensity will contain
a large error. The results measured on the three-beam structure show that quasi-longitudinal wave intensity can be accurately
measured using the intensity technique when bending waves are negligible in comparison with quasi-longitudinal waves.
The project supported by the National Natural Science Foundation of China 相似文献
994.
In this article the flows of perfect gas behind converging and diverging strong shock waves under isothermal condition in
the cases of spherical and cylindrical symmetry are examined. A diverging shock wave is formed by energy supply according
to a power law. These waves propagate in a uniform medium at rest and all conservation laws hold at the fronts of these shock
waves. It was established that in the case of converging waves for any value of the ratios of specific heats the solution of the problem under consideration exists and is unique. When the problem has more than one solution. In the case of diverging shock waves the solution exists and is unique for any from the interval and any value of power in the energy input law.
Received 4 August 1996 / Accepted 28 May 1996 相似文献
995.
Yu. E. Ivanova V. E. Ragozina 《Journal of Applied Mechanics and Technical Physics》2006,47(6):892-898
The method of matched asymptotic expansions was employed to obtain approximate solutions to the one-dimensional boundary-value
problems of nonlinear dynamic elasticity theory of impact loading on the surface of a cylindrical cavity of an incompressible
medium that causes antiplane motion or torsion of the medium. The expansion of the solution in the near-front region is based
on solutions of evolution equations different from the equations for quasi-simple waves.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 6, pp. 144–151, November–December, 2006. 相似文献
996.
997.
K. N. Gavrilova 《Journal of Applied Mechanics and Technical Physics》2004,45(1):37-44
A hyperbolic model of a shallow water flow is considered with allowance for nonlinear and dispersion effects. The structure of traveling waves above a flat bottom is studied. Stability of small disturbances of a homogeneous flow and development of instability of a nonstationary flow above an inclined bottom are analyzed. 相似文献
998.
强爆炸冲击波作用下天线结构的离散变量优化设计 总被引:1,自引:0,他引:1
首先建立了强爆炸冲击波作用下天线结构受精度和应力约束的连续变量优化设计数学模型 ;其次 ,根据材料特点 ,将设计变量取为离散变量 ,提出了天线结构在强爆炸冲击波作用下受精度和应力约束的离散变量优化设计数学模型。采用离散变量优化算法离散复合形法 ,对强爆炸冲击波作用下的 8m天线进行了优化计算。结果表明 ,经优化设计后 ,天线重量仅为初始重量的 4 0 %。 相似文献
999.
1000.
The solitary wave solutions for the Klein-Gordon-Schrodinger Equations were obtained by using the homogeaeous balance principle. The form of the solutions is more generalized than the result that has been proved by pure theoretical and qualitative method in literature;namely, the form of solutions in literature is a particular case of result of the present paper. 相似文献