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991.
A boundary layer analysis is used to investigate the effect of lateral mass flux on mixed convection heat and mass transfer over inclined permeable surfaces in porous media. The conservation equations that govern the problem are reduced to a system of non-linear ordinary differential equations and then the resulting equations is solved by numerical method. The numerical results for heat and mass transfer in terms of Nusselt and Sherwood number are presented in x-y plots for the buoyancy ratio (N) and Lewis number (Le) with mass flux pammeter (Fw). The obtained results are validated against previously published results with on special case of the problem. 相似文献
992.
V. G. Kozlov 《Fluid Dynamics》2004,39(1):3-11
The average vibrational motion of a nonisothermal fluid in a uniformly rotating cavity is described theoretically. Equations are obtained using the averaging technique in the high-frequency vibration approximation. It is found that the rotation significantly affects both the intensity of the average flows and the structure of the pulsatory velocity field generating resonance amplification of the fluid vibrations ar certain ratios of the rotation frequency and the force field oscillation frequency. This makes rotation an important controlling factor ensuring a strong averaged effect under relatively weak vibrational action. The problem of excitation of vibrational convection in a plane rotating layer is considered on the basis of the equations obtained when the vibration frequency substantially exceeds the rotation frequency. 相似文献
993.
用 HAAKE RV2 0型流变仪 ,在不同外加电场强度和不同颗粒体积分数下测试了基于沸石和硅油的电流变液的剪切应力变化 .结果表明 :随着外加电场强度升高 ,电流变液的零电场粘度急剧增加 ,电流变液的剪切屈服应力增加 ;随着电流变液中沸石颗粒体积分数升高 ,电流变液的剪切屈服强度急剧上升 .这种变化可以用颗粒间作用力与颗粒间距的关系、单位面积的颗粒链数目变化以及多体作用对电流变液性能的影响来解释 相似文献
994.
Surface deposition from fluid flow in a porous medium 总被引:3,自引:0,他引:3
The changes to porosity and permeability resulting from surface deposition and early dissolution in an initial rhombohedral
array of uniform spheres are studied. Very rapid decreases in permeability result from early deposition, with 48 percent reduction
predicted in permeability from 8 percent reduction in porosity. After deposition has caused about a 1 percent increase in
the radii of the spherical array, relative permeability reductions vary approximately as the square of relative changes in
porosity. These theoretical results are matched with experimental data of Itoi et al. and Moore et al. on deposition of silica. Satisfactory results are obtained in some cases, but for other cases a more complex model of the
porous medium is needed. 相似文献
995.
Francesco Sorge 《Meccanica》1995,30(1):37-52
Turbocompressor surge in a line with a long suction duct and plenum chamber is analysed using a distributed parameter propagation model which accounts for dynamic damping. The results, though obtained with simplifying assumptions, show very good agreement with experimental data.
Sommario Si studia il pompaggio di un turbocompressore centrifugo con lungo condotto di aspirazione e volume di raccolta alla mandata, adoperando un modello a parametri distribuiti ove si considera lo smorzamento dinamico ad opera dello strato limite di parete. L'accordo tra previsioni teoriche e dati sperimentali è ottimo, nonostante le semplificazioni introdotte.相似文献
996.
997.
通过引入位移函数,成功地研究了薄球壳在可压缩流体中的自由振动。发现存在两类自由振动:第一类与外界流体无关;第二类则受到流体性质的影响.证明了第二类振动的频率方程具有多项式形式并只存在复频率(除n=1时有Ω=0).求解n=0,1和2时的频率方程,并讨论参数的影响及给出根轨迹图。最后就小阻尼系数法作了对比分析。 相似文献
998.
999.
The cusped field thruster is a kind of newly developed electric propulsion device. The electric field at the channel exit and the low frequency oscillation were measured by former experiments. While the formation mechanism of them have not been fully interpreted yet. Through studying two distinguishing typical electron paths in the thrusters, a fluid model is built up along two electron paths, and then the model is completed by synthetically analyzing the effect of two electron paths. Time‐averaged electric potential distribution, anode current oscillation curve and time‐synchronized atom density and ion density distribution are obtained by simulation. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
This paper studies the trajectory asymptotic behavior of solutions for equations of a class of three-dimensional autonomous and incompressible non-Newtonian fluids. The authors prove the existence of the trajectory attractor for this class of equations in an appropriate topological space. ©, 2015, Chinese Academy of Sciences. All right reserved. 相似文献