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31.
J. L. Barron R. E. Mercer X. Chen P. Joe 《International journal of imaging systems and technology》2005,15(3):189-198
We present local least squares and regularization frameworks for computing 3D velocity (3D optical flow) from 3D radial velocity measured by a Doppler radar. We demonstrate the performance of our algorithms quantitatively on synthetic radial velocity data and qualitatively on real radial velocity data, obtained from the Doppler radar at Kurnell Radar station, Botany Bay, New South Wales, Australia. Radial velocity can be used to predict the future positions of storms in sequences of Doppler radar datasets.© 2005 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 189–198, 2005 相似文献
32.
In the present study a continuum model for one-dimensional plane Couette-Poiseuille flow is implemented to turbomolecular pumps in different flow regimes. Pumping performance of various turbomolecular pumps including 6 single rotors, a rotor-stator row, a rotor-stator-rotor row, and a multi-row with 13 alternative rotor-stator rows is considered here. The obtained results show that the model provides good quantitative values for pumping performance of turbomolecular pumps over the whole regimes ranging from molecular flow to transition to slip flow. 相似文献
33.
A. F. Kurbatskii 《High Temperature》2004,42(1):79-87
The difference in the turbulent diffusion between the active (heat) and passive (mass) scalars in a thermally stably stratified medium is investigated. The axisymmetric problem is treated on the formation of a turbulent circulation flow above a heated disk and on the turbulent diffusion of a passive scalar (impurity) from a continuous surface source in a stably stratified medium. The results indicate that the thermal stratification causes appreciable differences in the coefficients of turbulent transfer between the active (heat) and passive (mass) scalars. This means that the assumption of the identity of the coefficient of turbulent diffusion of heat and mass, employed in conventional models of turbulence, produces significant errors in estimating the heat and mass transfer in a thermally stably stratified medium. 相似文献
34.
35.
介绍了天铁炼钢厂中间包水模实验原理和过程,分析了斜、直、圆三种型式挡渣墙模拟结果,提出了合理的挡渣控流方案,在生产实践中使用效果良好。 相似文献
36.
River ice jams are a common occurrence on northern rivers, and their formation can present a severe flood risk to nearby communities. As more and more river regulation projects are developed to provide an alternative to fossil fuels for electrical power-generating capacity, our need to understand the mechanisms associated with ice jam formation under variable flow conditions becomes more vital. This is because, at present, hydropeaking operations are often severely curtailed during the ice-affected seasons due to concerns that sudden flow fluctuations might instigate ice jams and associated flooding. Here, an experimental investigation explores the effects of rapid increases in discharge on ice jam formation and evolution. It is found that the thickness of ice jams formed under highly dynamic flow conditions tend to be slightly thinner than those formed during steady carrier flows for comparable discharges. Also, despite the highly dynamic nature of these consolidation events, the resulting ice thicknesses appear reasonably well approximated by steady flow theory. 相似文献
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38.
官泓 《有色冶金设计与研究》2003,24(3):49-51
阐述水厂设计中对水厂规模、水源地、净水厂位置及净水工艺的确定过程,根据原水的特点,通过分析对无阀滤池进行改良。 相似文献
39.
Kang Hai-gui 《水动力学研究与进展(B辑)》1994,(2)
HYDRODYNAMIC FORCE ON SMOOTH HORIZONTAL CYLINDER IN UNIFORM OSCILLATORY FLOWHYDRODYNAMICFORCEONSMOOTHHORIZONTALCYLINDERINUNIF... 相似文献
40.
往复式压缩机管道的防振设计 总被引:1,自引:0,他引:1
分析了往复式压缩机管道产生振动的原因及影响因素,提出解决管道振动的方法及对策。 相似文献