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111.
112.
Ching-Yang Cheng 《Transport in Porous Media》2012,91(3):877-888
This work studies the Soret and Dufour effects on the double-diffusive free convection over a downward-pointing vertical truncated cone with variable wall heat and mass fluxes in fluid-saturated porous media. A coordinate transformation is used to derive the nondimensional boundary-layer governing equations, and the obtained nonsimilar equations are then solved by the cubic spline collocation method. Results for local surface temperature and the local surface concentration are presented as functions of Soret parameters, Dufour parameters, power-law exponents, buoyancy ratios, and Lewis numbers. Results show that increasing the Dufour parameter tends to increase the local surface temperature, while it tends to decrease the local surface concentration. An increase in the Soret number leads to a decrease in the local surface temperature for buoyancy assisting flows, while it leads to an increase in the local surface temperature for buoyancy opposing flows. Increasing the Soret number tends to increase the local surface concentration. Moreover, the local surface temperature and the local surface concentration of the truncated cones with higher power-law exponents are lower than those with lower exponents. 相似文献
113.
P. G. Siddheshwar R. K. Vanishree Anthony Christy Melson 《Transport in Porous Media》2012,92(2):277-288
The effects of temperature-dependent viscosity, gravity modulation and thermo-mechanical anisotropies on heat transport in a low-porosity medium are studied using the Ginzburg–Landau model. The effect of gravity modulation is to decrease the Nusselt number, Nu and variable viscosity leads to increase in Nu. The thermo-mechanical anisotropies have opposite effect on Nu with thermal anisotropy decreasing the heat transport. 相似文献
114.
Antonio Strozzi 《Journal of Elasticity》2012,108(1):119-123
The solution of cylindrical problems is addressed. A series solution is considered of the biharmonic equation, in which the series terms of the stress function Φ are expressions based upon Legendre polynomials and logarithmically singular functions. An explicit form of a polynomial supplementing each logarithmically singular part of the series solution is obtained. 相似文献
115.
We consider the flow of a viscous incompressible fluid in a pipe when the boundary is a deformable shell of Naghdi type. We prove that the corresponding system of partial differential equations has a solution when the deformation of the shell is smooth and small enough. We propose an algorithm that uncouples the unknowns and prove its convergence. 相似文献
116.
We apply the recently improved version of the 0–1 test for chaos to real experimental time series of laser droplet generation process. In particular two marginal regimes of dripping are considered: spontaneous and forced dripping. The outcomes of the test reveal that both spontaneous and forced dripping time series can be characterized as chaotic, which coincides with the previous analysis based on nonlinear time series analysis. 相似文献
117.
Energy density, magnetomechanical coupling factor and a dimensionless sensing gage factor of 〈1 0 0〉 oriented single crystal iron-gallium alloys with 16, 17.5, 19, 24.7 and 29 at% gallium were studied as functions of stress and magnetic field. To estimate these quantities, the samples were characterized under different quasi-static stress and magnetic field conditions. The experimental behavior was modeled using an energy-based non-linear approach. Both the experimental data and the model simulations were used to calculate material parameters such as magnetic permeability, piezo-magnetic strain coefficient (d33), inverse piezo-magnetic coefficient (stress sensitivity, d*33) and Young's modulus in the material. These quantities were used to obtain energy density, magnetomechanical coupling factor and sensing gage factor as functions of magnetomechanical conditions. Maximum energy density of around 3 kJ/m3, magnetomechanical coupling factor higher than 0.75 and sensing gage factor on the order of 103 were calculated. 相似文献
118.
We provide an affirmative answer to the C
r
-Closing Lemma, r ≥ 2, for a large class of flows defined on every closed surface. 相似文献
119.
Hairui Liu Zheng Lou Hui Wang Jungang Miao 《Journal of Infrared, Millimeter and Terahertz Waves》2009,30(4):401-409
A method of designing high performance millimeter wave quasi-optical Faraday rotators (QOFR) is reported in this paper. First,
the dielectric and magnetic parameters for the ferrite sample are determined by fitting theoretical curves to the measured
data. These fitted parameters are then used in a precise numerical model to predict the rotation angle and insertion loss
of the QOFR. Finally, the parameters of the QOFR are optimized according to the requirements of devices. Examples are given
showing the performance of the QOFR with an isolation better than 20 dB and an insertion loss less than 0.6 dB from 75 GHz
to 95 GHz. 相似文献
120.
Peter Bouwknegt Jarah Evslin Varghese Mathai 《Communications in Mathematical Physics》2015,337(2):909-954
We introduce spherical T-duality, which relates pairs of the form (P, H) consisting of a principal SU(2)-bundle \({P \rightarrow M}\) and a 7-cocycle H on P. Intuitively spherical T-duality exchanges H with the second Chern class c 2(P). Unless \({dim(M) \leq 4}\), not all pairs admit spherical T-duals and the spherical T-duals are not always unique. Nonetheless, we prove that all spherical T-dualities induce a degree-shifting isomorphism on the 7-twisted cohomologies of the bundles and, when \({dim(M) \leq 7}\), also their integral twisted cohomologies and, when \({dim(M) \leq 4}\), even their 7-twisted K-theories. While spherical T-duality does not appear to relate equivalent string theories, it does provide an identification between conserved charges in certain distinct IIB supergravity and string compactifications. 相似文献