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921.
Swati Mukhopadhyay Prativa Ranjan De Krishnendu Bhattacharyya G. C. Layek 《Meccanica》2012,47(1):153-161
A mathematical model is presented for analyzing the boundary layer forced convective flow and heat transfer of an incompressible
fluid past a plate embedded in a Darcy-Forchheimer porous medium. Thermal radiation term is considered in the energy equation.
The similarity solutions for the problem are obtained and the reduced nonlinear ordinary differential equations are solved
numerically. It is noticed that the boundary layer decreases with an increase in the value of inertial parameter and in this
case the temperature profile is found to decrease smoothly within the boundary layer. In case of porous plate, fluid velocity
increases whereas non-dimensional temperature decreases for increasing values of suction parameter. The rate of heat transfer
increases with the increasing values of Prandtl number. The effect of thermal radiation on temperature field is also analyzed. 相似文献
922.
An interfacial reaction during melt mixing of maleic anhydride copolymer (SMA) encapsulated single wall carbon nanotubes (SWNT) and polyamide 6 (PA6) was used in order to disperse SWNT homogeneously and to enhance interfacial adhesion. The intended reactive coupling between PA6 and SMA was evident from IR spectroscopy. Nanocomposites with SMA encapsulated SWNT showed increased elongation at break as compared to PA6/SWNT composites. SEM investigation of tensile fractured surfaces of PA6/SWNT+SMA composites indicated enhanced interfacial adhesion between PA6 and SMA modified SWNT. 相似文献
923.
S. Bhattacharyya Marina Dan A. K. Sen 《International Journal of Infrared and Millimeter Waves》2000,21(12):2065-2075
This paper describes a technique for modelling of rain drop size distributions at Calcutta in terms of negative exponential function, from the measurements of rain rate and attenuation over a dual wavelength LOS link at millimeter and optical frequencies. The DSD model obtained is then used to determine the attenuation at 94 GHz, for comparison with experimentally obtained attenuation at 94 GHz. This is also compared with the attenuation calculated by considering other experimentally obtained DSD models. The best fit negative exponential distribution function (modified M-P model) is presented along with some other experimentally obtained and reference models. 相似文献
924.
Edge plasma properties in a tokamak is an interesting subject of study from the view point of confinement and stability of
tokamak plasma. The edge plasma of SINP-tokamak has been investigated using specially designed Langmuir probes. We have observed
a poloidal asymmetry of floating potentials, particularly the top-bottom floating potential differences are quite noticeable,
which in turn produces a vertical electric field (Ev). This Ev remains throughout the discharge but changes its direction at certain point of time which seems to depend on applied vertical
magnetic field (Bv). 相似文献
925.
A two region conduction-controlled rewetting model of hot vertical surfaces with internal heat generation and boundary heat
flux subjected to constant but different heat transfer coefficient in both wet and dry region is solved by the Heat Balance
Integral Method (HBIM). The HBIM yields the temperature field and quench front temperature as a function of various model
parameters such as Peclet number, Biot number and internal heat source parameter of the hot surface. Further, the critical
(dry out) internal heat source parameter is obtained by setting Peclet number equal to zero, which yields the minimum internal
heat source parameter to prevent the hot surface from being rewetted. Using this method, it has been possible to derive a
unified relationship for a two-dimensional slab and tube with both internal heat generation and boundary heat flux. The solutions
are found to be in good agreement with other analytical results reported in literature. 相似文献
926.
Sirshendu Bhattacharyya Subinay Dasgupta 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(7):140
We study the dynamics caused by transport of transverse magnetization in one dimensional transverse Ising chain at zero temperature. We observe that a class of initial states having product structure in fermionic momentum-space and satisfying certain criteria, produce spatial variation in transverse magnetization. Starting from such a state, we obtain the transverse magnetization analytically and then observe its dynamics in presence of a homogeneous constant field Γ. In contradiction with general expectation, whatever be the strength of the field, the magnetization of the system does not become homogeneous even after infinite time. At each site, the dynamics is associated with oscillations having two different timescales. The envelope of the larger timescale oscillation decays algebraically with an exponent which is invariant for all such special initial states. The frequency of this oscillation varies differently with external field in ordered and disordered phases. The local magnetization after infinite time also characterizes the quantum phase transition. 相似文献
927.
Exact solutions for the flow of Casson fluid over a stretching surface with transpiration and heat transfer effects 下载免费PDF全文
The effects of transpiration on forced convection boundary layer non-Newtonian fluid flow and heat transfer toward a linearly stretching surface are reported.The flow is caused solely by the stretching of the sheet in its own plane with a velocity varying linearly with the distance from a fixed point.The constitutive relationship for the Casson fluid is used.The governing partial differential equations corresponding to the momentum and energy equations are converted into non-linear ordinary differential equations by using similarity transformations.Exact solutions of the resulting ordinary differential equations are obtained.The effect of increasing Casson parameter,i.e.,with decreasing yield stress(the fluid behaves as a Newtonian fluid as the Casson parameter becomes large),is to suppress the velocity field.However,the temperature is enhanced as the Casson parameter increases.It is observed that the effect of transpiration is to decrease the fluid velocity as well as the temperature.The skin-friction coefficient is found to increase as the transpiration parameter increases. 相似文献
928.
A. Zaib K. Bhattacharyya M. Khalid S. Shafie 《Journal of Applied Mechanics and Technical Physics》2017,58(3):419-424
The thermal radiation effect on a steady mixed convective flow with heat transfer of a nonlinear (non-Newtonian) Williamson fluid past an exponentially shrinking porous sheet with a convective boundary condition is investigated numerically. In this study, both an assisting flow and an opposing flow are considered. The governing equations are converted into nonlinear ordinary differential equations by using a suitable transformation. A numerical solution of the problem is obtained by using the Matlab software package for different values of the governing parameters. The results show that dual nonsimilar solutions exist for the opposing flow, whereas the solution for the assisting flow is unique. It is also observed that the dual nonsimilar solutions exist only if a certain amount of mass suction is applied through the porous sheet, which depends on the Williamson parameter, convective parameter, and radiation parameter. 相似文献
929.
930.
Some fatty acids, lipids, polymers and mesogenic molecules which are amphiphilic in nature spread at the air-water interface
to form stable Langmuir monolayers. They exhibit a rich variety of two-dimensional (2D) phases. In this article, we briefly
review some of the novel features we have found in these monolayers. For example, we find transition from a 2D monolayer to
three-dimensional structures possessing liquid crystalline order, induced liquid condensed phase, demixing of liquid expanded
phase, critical points and pattern formation. 相似文献