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61.
Steady state responses at viscous fluid/ orthotropic micropolar solid interfaces to moving point loads have been studied.
An eigenvalue approach using the Fourier transform has been employed to solve the problem. The displacement, microrotation
and stress components for the orthotropic micropolar solids so obtained in the physical domain are computed numerically by
applying numerical inversion technique. Viscosity and anisotropy effects on normal displacement, normal force stress and tangential
couple stress have been shown graphically for a particular model. Some special cases of interest have been presented. 相似文献
62.
We discuss the possibility of a quantum phase transition in ultra-cold spin-polarized Fermi gases which exhibit a p-wave Feshbach resonance. We show that when fermionic atoms form a condensate that can be externally tuned between the BCS and BEC limits, the zero temperature compressibility and the spin susceptibility of the fermionic gas are non-analytic functions of the two-body bound state energy. This non-analyticity is due to a massive rearrangement of the momentum distribution in the ground state of the system. Furthermore, we show that the low temperature superfluid density is also non-analytic and exhibits a dramatic change in behavior when the critical value of the bound state energy is crossed. 相似文献
63.
通过对玉米粉/玉米油电流变体(ER)的力学参数测试,研究了电场强度(E)、温度(T)和应变频率(f)对ER储能模量(G′)、耗散模量(G")及粘度系数(η′、η")的影响。实验结果表明:G′随E和f的增大而增大;G"随E的增大而增大,而随f的变化具有峰值特征,最大值发生在15~30Hz之间;η′、η"随E和f的变化与G′、G"的变化趋势相同;而温度的升高均使G′、G"、η′和η"值降低。 相似文献
64.
65.
采用数值模拟的方法对不同冲击波强度条件下界面的运动变化进行了数值模拟,探讨了冲击波强度对界面运动变化的影响,该研究为提高不同流体间的混合效果提供了依据。 相似文献
66.
B. J. Love 《Particulate Science and Technology》2004,22(3):285-290
Analytical modeling was used to track the mudline displacement of a simulated fluid dispersion that underwent a simulated linear increase in the fluid viscosity as a function of time following an induction period. Modeling results indicate two regimes of settling behavior from the driving force of density differences between the particles and the fluid. A linear mudline movement was first determined in the regime of constant viscosity, and a logarithmic retarded mudline movement was numerically determined following a linear rise in fluid viscosity. The results show that the combination of settling and solidification leads to a transitional mudline movement similar to batch settling curves described by early settling theories. 相似文献
67.
根据两个相对运动的平行板的流体处于简单剪切流状态的原理,设计制作了滑动平板式多功能流变体屈服应力测试装置.该装置用步进电机驱动,用单片机对步进电机进行精确定位和调速,并且由力传感器和应变仪来测量切应力数值,可以分别用于电流变液、磁流变液以及电磁流变液的测试.测试结果说明,该装置测量各种流变液都是有效的和实用的,且能保证一定的测量精度. 相似文献
68.
A non-Newtonian rheological model to investigate theoretically the effects of lubricant additives on the steady state performance of hydrodynamically lubricated finite journal bearings is introduced. In this model, the non-Newtonian behavior resulting from blending the lubricant with polymer additives is simulated by Stokes couple stress fluid model. The formed boundary layer at the bearing surface is described through the use of a hypothetical porous medium layer that adheres to the bearing surface. The Brinkman-extended Darcy equations are utilized to model the flow in the porous region. A stress jump boundary condition is applied at the porous media/fluid film interface. A modified form of the Reynolds equation is derived and solved numerically using a finite difference scheme. The effects of bearing geometry, and non-Newtonian behavior of the lubricant on the steady-state performance characteristics such as pressure distribution, load carrying capacity, side leakage flow, and coefficient of friction are presented and discussed. The results showed that lubricant additives significantly increase the load carrying capacity and reduce both the coefficient of friction and the side leakage as compared to the Newtonian lubricants. 相似文献
69.
70.
Kwannapat Sorachoti Bhuckchanya Pangkumhang Visanu Tanboonchuy Sarttrawut Tulaphol Nurak Grisdanurak 《中国化学工程学报》2017,25(6):768-774
Metalworking fluids(MWFs) are classified as hazardous substances. Due to the characteristics of the stable oil–water emulsions, it requires more costly and complicate treatment techniques to remove oil from spent MWFs. Metal organic frameworks(MOFs) are a porous network material used to remove contaminants from environment. One of the most prominent of MOFs is HKUST-1 or Cu-BTC. In this study, the Cu-BTCs were prepared by solvothermal method in various conditions and used as absorbent for removing oil micelles in MWF emulsion. The particle size of all synthesized Cu-BTCs ranged from ≈80 to 400 nm. The ability of all synthesized Cu-BTCs to remove oil micelle was greater than 95% in 60 min, while the capacity of GAC was obtained the result for only 6.8%. The maximum adsorption capacity(q _(max)) of oil micelles on Cu-BTCs was 1666.7 mg·g~(-1). The highest removal capacity of oil micelles in MWF emulsion is greater than 99% in 24 h by using Cu-BTCs washed with either butanol or ethanol. 相似文献