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991.
本文考虑轴向应力波效应,利用分叉理论研究各种支承半无限长弹塑性梁的动态屈曲问题。在轴向阶梯载荷和脉冲载荷冲击下得到了梁的临界屈曲载荷及初始屈曲模态。其结果与实验现象相一致。同时也为研究结构动态屈曲问题提供了有效途径。 相似文献
992.
A. A. Malysheva I. A. Malysheva 《Journal of Applied Mechanics and Technical Physics》2005,46(2):244-249
This paper gives results of an experimental study of incident and reflected waves of the bore type in the neighborhood of a sharp change in the channel bed level. It is shown that under conditions typical of accidents at ship locks, the wave height can reach 8 m.Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 2, pp. 115–121, March–April, 2005. 相似文献
993.
José Rául Quintero 《Journal of Dynamics and Differential Equations》2003,15(1):125-142
We study nonlinear orbital stability and instability of the set of ground state solitary wave solutions of a one-dimensional Boussinesq equation or one-dimensional Benney–Luke equation. It is shown that a solitary wave (traveling wave with finite energy) may be orbitally stable or unstable depending on the range of the wave's speed of propagation. 相似文献
994.
In this paper the complete Lie group classification of a non-linear wave equation is obtained. Optimal systems and reduced equations are achieved in the case of a hyperelastic homogeneous bar with variable cross section. 相似文献
995.
996.
I. I. Anik’ev M. I. Mikhailova E. A. Sushchenko 《International Applied Mechanics》2007,43(11):1264-1268
The behavior of a thin elastic plate with a rectilinear notch under the action a weak shock wave in air is studied experimentally.
A technique is developed for this purpose. The effect of the notch on the strain state of the plate is analyzed
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 11, pp. 99–104, November 2007. 相似文献
997.
The transition from regular reflection (RR) to Mach reflection (MR) as a plane shock wave diffracts around a triangular mountain of 45° inclination is analysed in this paper, both by optical
measurement in a shock tube and by numerical simulation the numerical method developed by Li Yingfan[1] is of the FLIC type with triangular mesh. The dependence of the critical transition point Lk ofRR→MR on shock Mach numberM
i
is analyzed and the variations of the incidence angle ω
i
of the impinging shock and the reflection angle ω
r
with the distanceL
* are investigated. Our experimental and numerical results agree well with the theoretical results of Iton and Italya. 相似文献
998.
999.
Critical conditions for the direct initiation of self-sustained detonation in cryogenic hydrogen-oxygen mixtures are examined experimentally. These initial conditions are expected to depend mainly on four parameters: the equivalence ratio of the mixture, the amount of the initial energy deposition, the initial temperature and pressure of the mixture. These critical conditions are determined by fixing alternatively three of these parameters and varying the fourth one from subcritical to supercritical detonation conditions. Results are presented for initial pressuresP
o and equivalence ratios ranging from 0.3 to 1 bar and from 1 to 2 respectively, for the two initial temperaturesT
o, 123 K and 293 K. These results indicate that for the lowest values of the initial pressure, a decrease of initial temperature may favour the onset of detonation. Whatever the initial conditions, the measured detonation pressures and velocities are in reasonably good agreement with the corresponding Chapman-Jouguet values computed using the ideal-gas equation of state. 相似文献
1000.
V. V. Ostapenko A. A. Malysheva 《Journal of Applied Mechanics and Technical Physics》2006,47(2):157-168
The solvability of the problem of the flows resulting from the incidence of a discontinuous wave on a bottom step is studied
using a single-layer shallow water model. Solutions in which the total energy of the flow is conserved at the step and those
in which it is lost at the step are considered. Regions of double and triple hystereses in the obtained self-similar solutions
are found. An analogy is drawn with the problem of single-layer flow over a bottom obstacle.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 2, pp. 8–22, March–April, 2006. 相似文献