Forced convection and sedimentation past a flat plate

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  • Forced convection.,
  • Sediments.,
  • Steady flow.,
  • Laminar flow.,
  • Particles.,
  • Viscous fluids.,
  • Suspending (Mixing)

Edition Notes

Book details

Statementby Nikolaos A. Pelekasis and Andreas Acrivos.
SeriesNASA contractor report -- NASA CR-204856
ContributionsAcrivos, Andreas., United States. National Aeronautics and Space Administration.
The Physical Object
Pagination1 v.
ID Numbers
Open LibraryOL17122699M

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Forced convection and sedimentation past a flat plate By NIKOLAOS A. PELEKASIS AND ANDREAS ACRIVOS The Levich Institute, City College of The City College of the City University of New York, th St & Convent Ave, New York NY,USA (Received 8.

The steady laminar flow of a well-mixed suspension of monodisperse solid spheres, convected steadily past a horizontal flat plate and sedimenting under Forced convection and sedimentation past a flat plate book.

Get this from a library. Forced convection and sedimentation past a flat plate. [Nikolaos A Pelekasis; Andreas Acrivos; United States. National Aeronautics and Space Administration.]. Forced Convection and Sedimentation Past a Flat Plate.

By Nikolaos A. Pelekasis and Andreas Acrivos. Abstract. The steady laminar flow of a well-mixed suspension of monodisperse solid spheres, convected steadily past a horizontal flat plate and sedimenting under the action of gravity, is examined.

It is shown that, in the limit as Re Author: Nikolaos A. Pelekasis and Andreas Acrivos. Forced convection heat transfer correlations for flow in pipes, past flat plates, single cylinders, single spheres, and for flow in packed beds and tube bundles Stephen Whitaker Department of Chemical Engineering University of California, Davis, Calif.

Cited by: and convection coefficients. We continue with parallel flow over flat plates. In Chapter 6, we solved the boundary layer equations for steady, laminar, par-allel flow over a flat plate, and obtained relations for the local friction coeffi-cient and the Nusselt number.

Using these relations as the starting point, we. To understand the convection heat transfer we must know some of the simple relations in fluid dynamics and boundary layer analysis.

Firstly we study boundary layer with forced convection flow systems. Boundary Layer over Flat Plate We consider the (x) direction along the wall with (y) direction normal to the wall as in Figure   Forced convection heat transfer correlations for flow in pipes, past flat plates, single cylinders, single spheres, and for flow in packed beds and.

Page 4. Forced Convection Heat Transfer In Chapter 3, we have discussed the problems ofheat conduction and used the convection as one ofthe boundaryconditions that can beapplied to the surface ofa conducting solid.

From studies of forced convection over flat plates in a wind tunnel, m =and for air Pr =so that r H / r M = Because the Prandtl number is independent of temperature (p. 30) and because micrometeorologists are rarely concerned with heat transfer in any gas except air, Pr m can be taken as constant in order to reduce Eq.

The analysis of forced convection flow past over a vertical porous flat plate embedded in an ethylene glycol-water-based nanofluid containing CuO, Al 2 O 3, and TiO 2 nanoparticles in a porous medium has been investigated by HAM. The results have been compared.

Heat transfer for a rectangular plate in cross-flow Description of the problem A heated rectangular plate (height d, span length Lz, negligible thickness) is placed in a uniform cross-flow (Figure ). We consider the rate of heat exchanged between the rear side of the plate and the fluid.

The lateral sides of the plate are. A similarity analysis is performed to study the fluid flow and heat transfer characteristics for the steady laminar forced convection boundary-layer flow past a semi-infinite horizontal plate in the presence of mass transfer, i.e., suction or blowing. Fig. 1 Free Convection from a vertical heated flat plate Fig.

2 Forced convection over a wedge Fig. 3 Analogy between free and forced convection 6th IASME/WSEAS International Conference on HEAT TRANSFER, THERMAL ENGINEERING and ENVIRONMENT (HTE'08) Rhodes, Greece, AugustISSN: ISBN: The convection and conduction heat flows are parallel to each other and to the surface normal of the boundary surface, and are all perpendicular to the mean fluid flow in the simple case.

Empirical correlations for the average Nusselt number for forced convection over a flat plate and circular and noncircular cylinders in cross flow. Churchill, S. W., and Ozoe, H., “ Correlations for Laminar Forced Convection with Uniform Heating in Flow over a Plate and in Developing and Fully Developed Flow in a Tube,” Journal of Heat Transfer, Vol.

95, pp. 78, (). convection can be divided in to different categories from different aspects. In the most general division, it is subdivided into free and forced convection. In the forced convection, the fluid to be heated is blown or pumped past the heated surface by employing a pump or a fan, while in the.

Forced and natural convection page 1. and causing laminar-to-turbulent transition earlier downstream than over a flat plate. If the pressure-gradient is adverse (i.e. positive, as in the upper part of Fig. 1, causing the fluid to decelerate) there can be Forced flow around a cylinder The flow past a two-dimensional cylinder in a.

where ρ 0 is the fluid density at temperature T 0, β = − [∂ρ/∂T] p /p is the volumetric coefficient of thermal expansion. Numerical values of β are usually small (water: β = × 10 −4, air: β = × 10 −3 at T = K), therefore the density variation is taken into account only in those cases where it affects the gravitational forces.

The Boussinesq approximation. The steady, two‐dimensional, incompressible laminar boundary‐layer flow of power law fluids past a semi‐infinite flat plate is studied analytically by the method of series expansion and the method of steepest descent (Meksyn's method).

The shear stress of the fluids considered is proportional to the nth power of the velocity gradient. Bahrami ENSC (F09) Forced Convection Heat Transfer 1 Forced Convection Heat Transfer Convection is the mechanism of heat transfer through a fluid in the Engine oil at 60°C flows over a 5 m long flat plate whose temperature is 20°C with a velocity.

View Chapter from ENG at University of Malaya. Chapter 5 EXTERNAL FORCED CONVECTION Drag and Heat Transfer in Internal Flow Parallel flow over flat plate Flow Cross Cylinders and. The forced convection model finds a correlation for rough­surface convection by applying the Colburn analogy to flat plates.

Through the use of effective­characteristic­length, the theory is extended to natural convection for all orientations of a plate. PARALLEL FLOW OVER FLAT PLATES. Consider the parallel flow of a fluid over a flat plate of length L in the flow direction, as shown in Fig.

19– x-coordinate is measured along the plate surface from the leading edge in the direction of the fluid approaches the plate in the x-direction with uniform upstream velocity ‘V and temperature Too.

Flow Over Flat Plate. The friction and heat transfer coefficient for a flat plate can be determined by solving the conservation of mass, momentum, and energy equations (either approximately or numerically).

Nusselt number can be expressed as: where C, m, and n are constants and L is the length of the flat plate. The HP Free and Forced convection from Flat Finned and Pinned Plates enables students to investigateheat transfer from various surfaces in free and forced convection.

The range of heated plates demonstratesthe effect of extended surfaces (fins and pins) on the rate of heat transfer. FLUENT - Forced Convection over a Flat Plate step 6; FLUENT - Forced Convection over a Flat Plate step 7; 4 more child pages.

Browse pages. Configure Space tools. Attachments (5) Page History Page Information Resolved comments Link to this Page View in Hierarchy.

This paper is devoted to the study of heat and mass transfer characteristics of some nanofluid flows past an infinite flat plate moving vertically. free/forced convection nanofluid flow. In the present study, forced convection flat plate SAH is constructed and investigated experimentally and analytically in five sunny days (2nd July, 3rd July, 4th July, 5th July and 6th July ).

The effects of varying air mass flow rate on its performance is discussed. Air mass. Horizontal Plate Isothermal Heated Natural Convection Equation and Calculator. Average heat transfer coefficient and plate temperature for an isothermal (constant temperature) heated horizontal flat plate's lower surface or a cooled plate's upper surface in a natural convection environment.

Example 1: Forced Convection and Flow Past a Horizontal Plate. Let’s consider the situation of modeling the flow past a horizontal flat plate with a length of 5 m, which is subjected to a constant and homogeneous heat flux of 10 W/m 2. The plate is placed in an airflow with an average velocity of m/s and temperature of K.

forced convection for evaluation of the coupled effects of heat and mass transport. They showed that all convection cases depend on different similarity variables. Yao et al., () studied forced convection due to a non-Newtonian fluid past a flat plate using a modified power-law viscosity model.

They showed that the most significant effects. Because most of the convective thermal resistance occurs close to the surface of a pipe or plate, it is reasonable to expect the turbulent correlations for pipe and plate to be related.

Forced Convection from a Rough Plate. Consider the similarity of Colburns's analogy (T) to T and T for forced convection on plates. An analysis is made for steady free convection about a vertical flat plate embedded in a saturated porous medium at high Rayleigh numbers. Within the framework of boundary layer approximations, similarity solutions are obtained for a class of problems where wall temperature varies as x λ, i.e., a power function of distance from the origin where wall temperature begins to deviate from that of.

Flow Profile Over a Flat Plate Two-dimensional flow analysis over a flat plate serves well to illustrate several key concepts in forced convection heat transfer. The viscosity of the fluid requires that the fluid have zero velocity at the plate's surface.

Postelnicu et al. investigated the effect of variable viscosity on forced convection over a horizontal flat plate in a porous medium with internal heat generation. Seddeek [ 17 ], Seddeek and Salem [ 18 ] studied the effects of chemical reaction, variable viscosity, and thermal diffusivity on mixed convection heat and mass transfer through.

Forced Convection on a Flat Disk Note: Please note the units of the quantities which are being measured, when recording data. For example, when measuring voltage, if the voltmeter reads 16 mV, then write down 16 mV instead of just The term ‘conjugate heat transfer’ refers to a heat transfer process involving an interaction of heat conduction within a solid body with either of the free, forced, and mixed convection from its surface to a fluid flowing over it.

It finds application in numerous fields starting from thermal interaction between surrounding air and fins to thermal interaction between flowing fluid and.

for forced convection heat transfer from flat plates, infinite circular cylinders, and spheres will be developed in the fol- lowing form: where Nu') is the area-averaged Nusselt number at the dif- fusive limit, C, is a constant that depends on the body shape, and F(Pr, 7,). Postelnicu, A.: Effects of thermophoresis particle deposition in free convection boundary layer from a horizontal flat plate embedded in a porous medium.

Int. Heat Mass Transf. 50, – () CrossRef Google Scholar. Free Convection 6 Free Convection [2] • Buoyancy is the result of difference in density between materials. • In this case, the difference in density is due to the difference in temperature.

• In the figure, the air next to the plate is heated, its density decreases, and the resulting buoyancy forces the air to rise.convection flow past a moving vertical plate in a porous medium in the presence of radiation and chemical reaction.

Comprehensive reviews of convective flow in porous media are candidly presented in the form of books and monographs by Ingham and Pop (), Ingham et al. (), Vafai () and Nield and Bejan ().Definition. The Nusselt number is the ratio of convective to conductive heat transfer across a boundary.

The convection and conduction heat flows are parallel to each other and to the surface normal of the boundary surface, and are all perpendicular to the mean fluid flow in the simple case. = = / = where h is the convective heat transfer coefficient of the flow, L is the characteristic length.

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