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921.
微幅振荡流体表面波图谱显示方法 总被引:10,自引:1,他引:10
本文介绍一种能够清晰显示微幅高频振荡的流体表面波图谱结构的方法和产生高达100Hz频率、波幅为毫米以下的流体表面波的实验装置,即改进了FARA-DAY实验装置。用本实验装置和显示方法获得了精美的波幅图,并就几种波图作了简要说明。 相似文献
922.
923.
提出分块波前法求解非对称大型有限元方程组,该方法综合分块解法和波前法的优点,根据计算机容量和方程的阶数优化计算过程,以在经济效率和存储效率之间达到平衡。本文利用该方法求解了轮胎稳态滚动有限元方程组,表明该方法是有效、可靠的。 相似文献
924.
We conducted dynamic and quasi-static compression experiments with low-density (ρ = 120 kg/m3) epoxy foam specimens. The specimens had a 10.0-mm-square cross-section and a length of 19.3 mm. Dynamic experiments were
conducted with a modified split Hopkinson pressure bar (SHPB), and the quasi-static experiments were conducted with a hydraulic
load frame device (MTS-810). In both cases, the specimens were loaded from one end at a constant velocity. Equally spaced
grid lines were marked on the specimens to monitor the deformation history. Digital images taken at equally spaced time intervals
gave the positions of each grid line. These images showed that a constant end-face velocity V produced a compaction wave front that traveled at a constant velocity C in both dynamic and quasi-static experiments. We described these results with a shockwave analysis that used a locking solid
material model. 相似文献
925.
926.
G. N. Puchka 《International Applied Mechanics》2006,42(5):568-573
The motion of gas bubbles in an inhomogeneous standing wave is examined. The nonlinear system of equations is solved by the
averaging method. Stationary solutions (bubble clusters) are found, and the conditions for their stability are established
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 5, pp. 88–94, May 2006. 相似文献
927.
François Marin Nizar Abcha Jérôme Brossard Alexander Ezersky 《Comptes Rendus Mecanique》2005,333(3):227-233
Interaction between solitons and a sandy bed in shallow water is investigated. In our experiments, solitons are generated on the background of a harmonic wave, in a wave flume used in resonant mode. It is found that the sand ripples formed by the solitons propagation induce a significant decrease of solitons amplitude and of the phase shift between the soliton and the harmonic wave. However, the amplitude of the harmonic wave is approximately constant. The possible physical processes of such behaviour for the soliton amplitude and for the harmonic wave amplitude are discussed. To cite this article: F. Marin et al., C. R. Mecanique 333 (2005). 相似文献
928.
929.
V. M. Kulik 《Journal of Applied Mechanics and Technical Physics》2006,47(3):394-400
The velocity and the rate of decay of a strain wave in a layer of a viscoelastic material rigidly fixed on a solid foundation
are determined. The wave structure (ratio of the longitudinal to the transverse displacement) and the profiles of these displacements
are analyzed. Attenuation of waves in the first mode is found to be more significant than that in an infinite space. The most
intense decay is observed at resonance frequencies. A strong effect of compressibility of the medium on wave parameters is
revealed. Conditions at which such a system operates as a waveguide are found. For a loss tangent higher than 0.13 (for an
incompressible medium), the character of the dispersion dependence is observed to change drastically: the wave velocity decreases
with decreasing frequency.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 104–111, May–June, 2006. 相似文献
930.
作者在用摄影法进行坚直椭圆管内降膜波动实验研究时证实,当Re<400时,降膜内确实存在孤立波;R_(?)>400时,存在随机波.降膜中的孤立波是由小扰动发展而成的.实验结果与理论预测的孤立波特性吻合较好. 相似文献