表面张力、黏性和驱动对非传播表面孤立波的影响

从理论上研究了表面张力、黏性和驱动对非传播表面孤立波的影响。指出表面张力使孤波高度增大、宽度减小．作出了孤波的等波响应曲线（ｅｑｕａｌ－ｗａｖｅ－ｒｅｓｐｏｎｓｅ－ｃｕｒｖｅｓ）并与实验结果进行了比较。     

弦的非线性振动摄动法及其K—dV方程的孤波解

本文用摄动法导出了弦的非线性振动的Ｋ－ｄＶ方程，讨论了只有耗散和色散的特殊情况，然后详细讨论了Ｋ－ｄＶ方程的孤波解的性态，并给出了弦的非线性振动孤波的主要特征。     

Kupershmidt浅水波方程的线性化,相似约化和孤波解

利用未知函数变换方法，找到了Ｋｕｐｅｒｓｈｍｉｄｔ方程到Ｂｕｒｇｅｒｓ方程及热传导方程间的Ｂａｃｋｌｕｎｄ变换并借此给出了Ｋｕｐｅｒｘｈｍｉｄｔ方程四种杨似约化和一组孤波解。     

弹性介质中几何和运动非线性问题的类孤波解

将弹性介质 的几何和运动非线性方程简化成具有电磁场中的Ｂｏｒｎ－Ｉｎｆｅｌｄ方程的形式，并证明了该方程的类孤波解的存在．     

非线性弹性杆中的应变孤波

本文对非线性弹性杆中的应变孤波进行了分析,着重讨论了杆的物理参数和几何参数对于波动的影响,阐明了孤波传播过程的主要特征。     

非传播孤立波和表面张力

本文讨论了关于表面张力的实验与理论分析之间的矛盾把表面张力的能量当作高阶小量、导出了非传播孤立波的基本方程，得到的解与实验结果相符。     

非传播孤立波和表面张力

讨论关于表面张力的实验与理论分析之间的矛盾．把表面张力的能量当作高阶小量、导出了非传播孤立波的基本方程，得到的解与实验结果相符．     

化学反应体系中的孤波

本文研究了化学反应扩散方程的动态行为,对于双分子过程得到了近似的孤波;对三分子过程,求得了扭结状的浓度孤波。 1.化学反应扩散方程可以用来描述许多生物化学过程。文献[1]曾详细讨论了单分     

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借助Ｍａｔｈｅｍａｔｉｃａ,采用直接约化法获得ＭＤＷＷ方程的３种对称约化．经过一系列变换,将ＭＤＷＷ方程约化为著名的１＋１维Ｂｕｒｇｅｒｓ方程,进而得到ＭＤＷＷ方程更多形式的约化和若干精确解,其中包括孤波解．     

孤立波与多孔介质结构物的非线性相互作用

基于精确至Ｏ（εμ＾２,μ＾４）的多孔介质无压渗流模型方程和均匀流体质波动的Ｂｏｕｓｓｉｎｅｓｑ方程,本文对孤立波与多孔介质结构物的相互作用了较系统的数值实验。控制方程采用基于有限差分方程离散,在时域上采用了预估－校正方法进行了时间积分。在求解演化方程的过程中,引入“内迭代”过程实现流体域和多孔介质交界面的连接条件。结果表明孤立波在多孔介质上的反射与在不可渗透的界面上的反射类似,形成反向的孤立波但     

Shape of the free surface of a magnetic fluid containing a cylindrical concentrator of the magnetic field

The shape of the surface of a magnetic fluid containing a cylindrical body made of a well-magnetizable material (magnetic field concentrator) in a uniform applied magnetic field is studied experimentally and theoretically. Various static shapes of the surface are calculated numerically taking into account the gravity forces, the surface tension, and the dependence of the magnetic fluid magnetization on the magnetic field strength. It is found that there exists several equilibrium shapes of the magnetic fluid surface. Abrupt changes in the magnetic fluid surface and its hysteresis are predicted theoretically and observed experimentally. The theoretical and experimental results are compared.     

On the lamb solution and Rayleigh-wave-induced cracking

This paper examines the extension of surface microcracks induced by a surface or Rayleigh wave (R-wave). This problem is examined both theoretically and experimentally. The theoretical approach involves a full-field reappraisal of the Lamb solution for a surface wave propagating in a homogeneous, isotropic, elastic, two-dimensional material for the cases of plane strain and plane stress. Using the Griffith-Irwin energy-release-rate fracture criterion for cracks under combined Mode I and Mode II loading, a prediction is made of the path and final length of the surface microcrack extension produced by the R-wave. Predictions of the crack-extension direction are also obtained using the maximum normal-stress fracture criterion. The experimental approach uses dynamic photoelasticity to observe the isochromatic patterns associated with an R-wave propagating along the narrow edge of a transparent birefringent plate, examining in detail the process of crack extension. When the theoretically and experimentally obtained results are compared, reasonable agreement is obtained.     

Structural Stability of Unsteadily Accelerated Liquid Pistons

The possibility of the fragmentation of a liquid piston moving with variable acceleration, due to air jets forming on its free surface and penetrating inward, is established experimentally. The liquid piston acceleration regimes in which air jets capable of penetrating into the liquid are formed from initial perturbations on its free surface are theoretically analyzed.     

Experimental and Theoretical Investigation of Surface Electrization in a Combustion Product Flow

The electrization of cooled and non-cooled surfaces in a combustion product flow loaded with charged soot particles is investigated experimentally and theoretically. The charging currents of the inner surface of a cylinder located in a combustion (propane in air) product flow with a relatively high soot content and the charging currents of cooled and non-cooled cylinders located in a combustion product jet with a relatively low soot content are determined. Physico-mathematical models are constructed for the new effects observed experimentally and these models are theoretically and numerically analyzed.     

The propagation of elastic surface waves along cylindrical cavities of general cross section

The existence of surface wave modes, propagating along an infinite cylindrical cavity of arbitrary constant cross section in an elastic medium, is investigated theoretically. A general secular equation is derived using the null-field approach and global expansions of the surface displacements. Numerical results for the phase velocities, surface displacements and cut-off frequencies are presented for elliptic cross sections. The largest eccentricity considered is 0.99995 and it is inferred that the flexural mode exists at all frequencies for any eccentricity of the cross section.     

Localization of Shear Waves Near Layers Separating Two Regularly Laminated Half-Spaces

The existence conditions for surface and normal shear waves in finite and infinite periodically laminated structures with broken translational symmetry are studied theoretically and numerically. The problems posed are reduced to systems of linear algebraic equations. The existence condition for their nontrivial solutions yield dispersion relations. Conditions for the existence of surface and normal shear waves are established. Some results are plotted. The dependence of the dispersion spectrum on the physical and geometrical properties of the symmetry breaker is studied__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 1, pp. 128–134, January 2005.     

An experimental validation of load distribution in screw threads

The thread load distribution has been examined, as is known, in literature both theoretically and experimentally. in the present paper the load distribution is validated by strain-gage measurements. Starting from the theoretical load distribution the stresses on the outer surface of the female member of a threaded connection are calculated. The theoretical and experimental stress values obtained are reasonably close.     

Instability of the magnetic fluid shape in the field of a line conductor with current

The static shape of the surface of a finite magnetic fluid volume between horizontal plates is investigated theoretically. The nonuniform magnetic field is generated by a horizontal line conductor with current, which is placed above the upper plate. The variational problem of minimum energy relative to plane surface perturbations is considered for a simply connected magnetic fluid volume. The problem is solved for arbitrary magnetic fields in the noninductive approximation with account for the gravity force and surface tension. Unstable solutions are found. The possibility of stepwise behavior in response to quasi-static changes of the current in the conductor is investigated for the surface shape of a finite magnetic fluid volume.     

Preload-responsive adhesion of microfibre arrays to rough surfaces

Adhesion of bio-inspired microfibre arrays to a rough surface is studied theoretically. The array consists of vertical elastic rods fixed on a rigid backing layer,and the surface is modeled by rigid steps with a normally distributed height. Analytical expressions are obtained for the adhesion forces in both the approach and retraction processes. It is shown that, with the increasing preload, the pull-off force increases at first and then attains a plateau value. The results agree with the previous experiments and are expected helpful in adhesion control of the array in practical applications.