The Experts below are selected from a list of 3339 Experts worldwide ranked by ideXlab platform
Arun S Mujumdar - One of the best experts on this subject based on the ideXlab platform.
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Simultaneously Developing Flow and heat transfer of non-Newtonian fluids in equilateral triangular duct
Applied Mathematical Modelling, 1996Co-Authors: S.gh. Etemad, Arun S Mujumdar, R. NassefAbstract:Abstract A numerical investigation based on the Galerkin finite element method was carried out to solve the full three-dimensional governing equations for Simultaneously Developing steady laminar Flow and heat transfer to a purely viscous non-Newtonian fluid described by a power law model Flowing in equilateral triangular ducts. Two commonly used thermal boundary conditions, constant wall temperature (T boundary condition) and constant wall heat flux both axially and peripherally (H2 boundary condition) were examined. It is shown that the Nusselt number distribution along the walls is affected appreciably by the variation of the power law index. Results are presented and discussed for a wide range of power law indices and Prandtl numbers for T and H2 boundary conditions.
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effects of variable viscosity and viscous dissipation on laminar convection heat transfer of a power law fluid in the entrance region of a semi circular duct
International Journal of Heat and Mass Transfer, 1995Co-Authors: Gh S Etemad, Arun S MujumdarAbstract:Abstract A numerical scheme based on Galerkin's finite element method was used to solve the three-dimensional governing equations for steady laminar Simultaneously Developing Flow and heat transfer in a semi-circular duct. Two different boundary conditions, constant wall heat flux both axially and peripherally and constant wall temperature, were considered. The study was conducted for a purely viscous non-Newtonian fluid with different power law indices and Prandtl numbers. The effects of temperature dependent viscosity and viscous dissipation were examined and discussed.
Himadri Chattopadhyay - One of the best experts on this subject based on the ideXlab platform.
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transport phenomenon of Simultaneously Developing Flow and heat transfer in twisted sinusoidal wavy microchannel under pulsating inlet Flow condition
E3S Web of Conferences, 2019Co-Authors: Suvanjan Bhattacharyya, Himadri Chattopadhyay, Ali Cemal Benim, M A MoghimiAbstract:The transport phenomena in microchannel are significant in designing MEMS devices. The current study investigates numerically the Simultaneously Developing unsteady laminar Flow and heat transfer inside a twisted sinusoidal wavy microchannel. At the inlet sinusoidal varying velocity component is applied. Varying pulsating amplitude and frequency represented by the Strouhal number was studied for Reynolds numbers ranging from 1 to 100. The governing equations are solved with a finite volume based numerical method. In comparison with steady Flow, it was found that imposed sinusoidal velocity at the inlet can provide improved heat transfer performance at different amplitudes and frequencies while keeping the pressure drop within acceptable limits.
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Numerical investigations of Simultaneously Developing Flow in wavy microchannels under pulsating inlet Flow condition
International Communications in Heat and Mass Transfer, 2013Co-Authors: Tapas K. Nandi, Himadri ChattopadhyayAbstract:Abstract The Simultaneously Developing unsteady laminar fluid Flow and heat transfer inside a two dimensional wavy microchannel, due to sinusoidally varying velocity component at inlet has been numerically investigated. The Flow was both thermally and hydrodynamically Developing while the channel walls were kept at a uniform temperature. The transient solution of two-dimensional Navier-Stokes equation was obtained using the SIMPLE algorithm with the momentum interpolation technique of Rhie and Chow. The simulation was performed in the laminar regime for Prandtl number 7 and Reynolds number ranging from 0.1 to 100. Based on the comparison with steady Flow in wavy channel it was found that imposed sinusoidal velocity at inlet can provide improved heat transfer performance at different amplitude (0.2, 0.5, 0.8) and frequency (1, 5, 10).
Joao N. N. Quaresma - One of the best experts on this subject based on the ideXlab platform.
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Eigenfunction Expansion Solution for Boundary-Layer Equations in Cylindrical Coordinates: Simultaneously Developing Flow in Circular Tubes
Numerical Heat Transfer Part A: Applications, 2007Co-Authors: S. P. A. Paz, Emanuel Negrão Macêdo, Joao N. N. Quaresma, Renato M. CottaAbstract:The Generalized Integral Transform Technique (GITT) is employed, via a novel eigenfunction expansion, in the solution of the steady-state continuity, momentum, and energy equations under the boundary-layer formulation and cylindrical coordinates, and applied to the solution of Simultaneously Developing laminar Flow inside circular ducts. The streamfunction formulation is adopted to automatically satisfy the continuity equation and to eliminate the pressure field. A fourth-order eigenvalue problem is thus considered for the velocity field, eliminating the difficulties associated with the singularity at the channel centerline through this recently introduced expansion basis. A thorough analysis of convergence behavior is undertaken for both the velocity and temperature proposed eigenfunction representations, and here illustrated for representative values of governing parameters and positions along the channel. Results for quantities associated with applications, such as the product of the friction factor–Re...
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Solutions for the internal boundary layer equations in Simultaneously Developing Flow of power-law fluids within parallel plates channels
Chemical Engineering Journal, 2002Co-Authors: Rui Nelson Otoni Magno, Emanuel Negrão Macêdo, Joao N. N. QuaresmaAbstract:Abstract The generalized integral transform technique (GITT) is employed in the solution of the boundary layer equations in Simultaneously Developing laminar Flow of power-law non-Newtonian fluids within a parallel plates channel. In the modeling of the related momentum and energy equations within the range of validity of the boundary layer equations, a streamfunction formulation is employed which offers a better computational performance than the primitive-variables formulation. Numerical results for the bulk temperature and Nusselt numbers are established at different axial positions along the channel and for various power-law indices, and critical comparisons with previously reported works in the literature are also performed.
Tapas K. Nandi - One of the best experts on this subject based on the ideXlab platform.
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Numerical investigations of Simultaneously Developing Flow in wavy microchannels under pulsating inlet Flow condition
International Communications in Heat and Mass Transfer, 2013Co-Authors: Tapas K. Nandi, Himadri ChattopadhyayAbstract:Abstract The Simultaneously Developing unsteady laminar fluid Flow and heat transfer inside a two dimensional wavy microchannel, due to sinusoidally varying velocity component at inlet has been numerically investigated. The Flow was both thermally and hydrodynamically Developing while the channel walls were kept at a uniform temperature. The transient solution of two-dimensional Navier-Stokes equation was obtained using the SIMPLE algorithm with the momentum interpolation technique of Rhie and Chow. The simulation was performed in the laminar regime for Prandtl number 7 and Reynolds number ranging from 0.1 to 100. Based on the comparison with steady Flow in wavy channel it was found that imposed sinusoidal velocity at inlet can provide improved heat transfer performance at different amplitude (0.2, 0.5, 0.8) and frequency (1, 5, 10).
Michael K. Jensen - One of the best experts on this subject based on the ideXlab platform.
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Mixed convection laminar Flow and heat transfer of liquids in isothermal horizontal circular ducts
International Journal of Heat and Mass Transfer, 1995Co-Authors: Biswadip Shome, Michael K. JensenAbstract:Abstract Numerical analysis of thermally Developing and Simultaneously Developing mixed convection Flow and heat transfer with variable viscosity in an isothermal horizontal tube has been carried out. Parametric computations were performed to investigate the effect of inlet Prandtl number, inlet Rayleigh number, wall-to-inlet temperature difference, and inlet axial velocity profile on the Nusselt numbers and apparent friction factors for both heating and cooling conditions. The results indicate that the effect of variable viscosity is more pronounced on the friction factor than on Nusselt numbers. In addition, the effect of inlet Rayleigh number and inlet velocity profile on the Nusselt numbers and friction factors exists only in the near-inlet region. A parameter found by scaling analysis was used to empirically correlate the computed Nusselt number and the friction factor data and the available experimental Nusselt number data for both thermally Developing and Simultaneously Developing Flow and heat transfer. The developed correlations are more accurate, have wider ranges of applicability than those available in the literature, and should be of much use to designers.
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COMBINED CONVECTION AND RADIATION IN Simultaneously Developing Flow AND HEAT TRANSFER WITH NONGRAY GAS MIXTURES
Numerical Heat Transfer Part A-applications, 1994Co-Authors: Deborah A. Kaminski, Michael K. JensenAbstract:Abstract Combined convection and radiation in Simultaneously Developing laminar Flow and heat transfer in a smooth tube is numerically considered with the P-I approximation and the exponential wideband model. The fluid is a mixture of carbon dioxide, water vapor, and nitrogen, The bulk mean temperature variation, temperature profiles, and Nusselt numbers are shown for a uniform inlet temperature and several constant wall temperatures. Nusselt numbers for Simultaneously Developing Flow are compared with those for thermally Developing Flow. The effects of the mole fraction of the nongray gases and the wall emissivity on convective and radiative Nusselt numbers are explored.