The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform
Ashok K. Singh - One of the best experts on this subject based on the ideXlab platform.
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Transient free convective flow in a vertical channel with Constant temperature and Constant Heat Flux on walls
Heat and Mass Transfer, 1996Co-Authors: Trishna Paul, Basant K. Jha, Ashok K. SinghAbstract:This note presents transient motion of a viscous and incompressible fluid in a vertical channel due to free convective currents occuring as a result of application of Constant Heat Flux at one wall and Constant temperature on other wall. The method of Laplace transform is used to solve the problem. The transient behaviour of flow on velocity and temperature fields are shown on the graphs.
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An exact solution for unsteady magnetohydrodynamic free convection flow with Constant Heat Flux
International Communications in Heat and Mass Transfer, 1994Co-Authors: Nirmal C. Sacheti, Pallath Chandran, Ashok K. SinghAbstract:Abstract The unsteady hydromagnetic free convection flow of a viscous incompressible and electrically conducting fluid generated by an impulsively moving vertical plate subject to Constant Heat Flux at the plate has been considered. The dimensionless parameters governing the problem are the Prandtl number, the Grashof number and the Hartmann number. An exact solution has been obtained for this problem using Laplace transform. Velocity and skin friction of the flow have been presented for water, and the influence of the governing parameters has been discussed. In particular, the magnetic field has a retarding effect on the velocity while skin friction at the plate increases with it.
P. Ganesan - One of the best experts on this subject based on the ideXlab platform.
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Magnetic field effect on a moving vertical cylinder with Constant Heat Flux
Heat and Mass Transfer, 2003Co-Authors: P. Ganesan, P. LoganathanAbstract:An analysis is performed to study the unsteady incompressible flow over a moving vertical cylinder with Constant Heat Flux and magnetic field applied normal to the surface. The nonlinear-coupled parabolic partial differential equations governing the flow and Heat transfer have been solved numerically using a finite difference scheme of Crank-Nicolson type. The numerical results are presented for the velocity, temperature, local and average skin-friction and Nusselt number. It is observed that the presence as well as increase in the magnetic field leads to decrease in the velocity field and rise in thermal boundary thickness.
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Effects of mass transfer and flow past a moving vertical cylinder with Constant Heat Flux
Acta Mechanica, 2001Co-Authors: P. Ganesan, P. LoganathanAbstract:The authors present a numerical investigation of laminar natural convection flow past a moving semi-infinite vertical cylinder subjected to Constant Heat Flux. The transformed governing equations are obtained and solved using an implicit finite difference scheme of Crank-Nicolson type. Numerical results for the transient velocity, the temperature and the concentration profiles are shown graphically. It is observed that there is a rise in temperature due to the presence of mass diffusion. The local as well as average skin friction, and the rate of Heat and mass transfers are shown graphically.
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Flow past an impulsively started vertical plate with Constant Heat Flux and mass transfer
Computer Methods in Applied Mechanics and Engineering, 2000Co-Authors: R. Muthucumaraswamy, P. GanesanAbstract:Finite-difference solution of the transient natural convection flow of an incompressible viscous fluid past an impulsively started semi-infinite plate with Constant Heat Flux and mass transfer is presented here. The Velocity profiles are compared with exact solution and are found to be in good agreement. The steady-state velocity, temperature and concentration profiles are shown graphically. It is observed that there is a rise in the velocity due to the presence of a mass diffusion. The local as well as average skin-friction, Nusselt number and Sherwood number are shown graphically.
Andrew Ramsay Knox - One of the best experts on this subject based on the ideXlab platform.
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Transient response of a thermoelectric generator to load steps under Constant Heat Flux
Applied Energy, 2018Co-Authors: Marcos Compadre Torrecilla, Andrea Montecucco, Jonathan Siviter, Andrew Strain, Andrew Ramsay KnoxAbstract:Abstract Most waste Heat recovery applications involve a Heat source that provides a limited Heat Flux that can be converted into electricity by a thermoelectric generator (TEG). When a TEG is used under limited or Constant Heat Flux conditions the temperature difference across the device cannot be considered Constant and will change depending on the electrical current generated by the TEG. This phenomenon is induced by the Peltier effect, which works against power generation and deviates the optimum operating point from the commonly known maximum power point (MPP). This point, dictated by the maximum power transfer theorem, is achieved when the source equivalent series resistance and the load resistance are equal, in conditions of Constant temperature difference. Hence maximum power point tracking (MPPT) algorithms that regulate the TEG at half of the instantaneous open-circuit voltage are optimized only for applications where the TEG operates under Constant temperature difference but are not ideal for Constant Heat Flux conditions. Hill climbing MPPT methods, e.g., perturb-and-observe (P&O) or incremental conductance (IC), can reach the MPP more accurately if the sampling time is extended to the thermal time Constant of the system. This article presents an analysis of the transient electrical and thermal response of a TEG to a load change. This investigation results fundamental to the design of MPPT algorithms such P&O or IC for TEGs operating under Constant Heat Flux. A step-up (boost) dc-dc converter controlled by P&O is used to demonstrate the effects of the sampling time over of the transient response and hence the tracking performance of the MPPT algorithm.
R.r. Johnson - One of the best experts on this subject based on the ideXlab platform.
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Heat transfer characteristics of a Constant Heat Flux vertical plate in water
Experimental Thermal and Fluid Science, 1994Co-Authors: H.e. Imadojemu, R.r. JohnsonAbstract:Experimental examination of the Heat transfer characteristics of a vertical plate in water is presented. Results are given as the variation of local Nusselt number with Rayleigh number for different Heat Fluxes. The experiments included temperature measurements and flow visualization by the use of the simple and precise method of electrochemical formation of dye technique. Arrangements were made so that color changes occured both at the surface of the vertical plate and within the boundary layer. The free convection Heat transfer in water, as expressed by the power-law relationship between the Nusselt number and Rayleigh number, Nu = 0.89 Ra0.2, is shown to be adequate for the range of Rayleigh numbers 104 < Ra < 1013 for a Constant Heat Flux boundary condition. There appear to be similarities in the mechanisms of transition from laminar to turbulent boundary layer flow between those for natural convection and those for the Blasius-type forced flow over a flat plate. The Emmons spot source band for natural convection flow is large when compared to the narrow band for Blasius flow.
Behrang Jaberi - One of the best experts on this subject based on the ideXlab platform.
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Heat transfer characteristics of impinging jet on a hot surface with Constant Heat Flux using cu2o water nanofluid an experimental study
International Communications in Heat and Mass Transfer, 2020Co-Authors: Mohsen Amjadian, Habibollah Safarzadeh, Mehdi Bahiraei, Saeed Nazari, Behrang JaberiAbstract:Abstract The experimental investigations are carried out on a circular nanofluid jet impingement for cooling an aluminum disk with Constant Heat Flux. The study is performed to understand the effects of different factors such as Reynolds number and nanoparticle concentration on the fluid flow and characteristics of Heat transfer. The target surface has a circular shape and is kept at Constant Heat Flux with the value of 1414.71 W/m2. The copper oxide-nanoparticle concentrations are changed from 0.03 to 0.07 wt%. The experimental results show that the Cu2O nanofluid increases the Heat transfer efficiency of the impinging jet cooling system. Compared to the case of using the base fluid, the nanofluid increases the convective Heat transfer by 45% at 0.07 wt% concentration at Reynolds number of 7330. The center of the target surface, i.e. the stagnation zone, has the highest turbulence intensity because of impinging of the fluid flow on the surface center, while the endpoint of the target surface has the minimum turbulence intensity. Indeed, the turbulence intensity decreases along the radial direction, which augments the effect of employing the nanofluid because the Heat transfer due to the turbulence diminishes and merit of using the nanofluid enhances.