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991.
A high-speed photographic study of the transition from deflagration to detonation wave 总被引:2,自引:0,他引:2
Experiments were conducted to investigate the DDT process of the oxyhydrogen gas in the rectangular detonation tube of 3 m
long. The repeated obstacle was installed near the ignition plug and the effects of the obstacle on the DDT process were investigated.
The behaviour of the combustion and detonation wave were visualized utilizing Imacon high-speed camera with the aid of Schlieren
optics.
As a result, DDT process was visualized, i.e. (i) multiple shock waves were induced by the expanding combustion wave, because
the combustion flame played a role as a piston and compressed the unburned gases. (ii) The acceleration of the combustion
wave was occurred and the distance between the shock wave and the combustion flame became shorter. (iii) Eventually, the local
explosion was occurred and cause overdriven detonation wave to propagate at the velocity of about 3 kms−1.
An abridged version of this paper was presented at the 15th Int. Colloquium on the Dynamics of Explosions and Reactive Systems
at Boulder, Colorado, from July 30 to August 4, 1995 相似文献
992.
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
993.
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
994.
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
995.
研究了振动波在含有环向表面裂纹的无限长圆柱壳中的传播特性.圆柱壳体的振动用Flügge方程来描述.运用线弹性断裂力学的理论,考虑到裂纹的张开、滑移和撕裂3种模式以及它们相互之间的耦合,利用分布的线弹簧来模拟裂纹并建立了裂纹所在区域的局部柔度矩阵,得到由此引起的附加位移和壳体中内力之间的关系.在入射波已知的情况下,根据裂纹两侧区域的位移和内力的连续性条件得到了反射和透射波的幅值系数.分析了入射波通过裂纹后的透射、反射系数与激励频率和裂纹尺寸之间的关系.为基于振动功率流方法识别圆柱壳表面损伤提供了理论基础. 相似文献
996.
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
997.
A. M. Zenkour 《Archive of Applied Mechanics (Ingenieur Archiv)》2004,74(3-4):262-276
Summary The static and dynamic responses of anisotropic spherical shells under a uniformly distributed transverse load are investigated.
Analytical solutions using the mixed variational formulation are presented for spherical shells subjected to various boundary
conditions. Numerical results of a refined mixed first-order shear deformation theory for natural frequencies, critical buckling,
center deflections and stresses are compared with those obtained using the classical shell theory. A variety of simply-supported
and clamped boundary conditions are considered and comparisons with the existing literature are made. The sample numerical
results presented herein for global structural behaviour of monoclinic spherical shells should serve as references for future
comparisons. 相似文献
998.
999.
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
1000.
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