Leading Edge Effects in Transient Natural Convection Flow adjacent to a Vertical Surface

This paper presents a comprehensive mathematical model and numerical solutions for a natural convection flow over an isothermal, heated, vertical wall immersed in an ambient atmosphere that is thermally stratified. The model assumes a laminar flow near the leading edge, which then becomes a transitional flow, and finally becomes fully turbulent away from the leading edge. Effects of several typical cases of ambient stratification on heat transfer to the wall, peak velocity, and temperature are examined. It is found that the velocity field is affected more significantly by the “memory” of upstream ambient conditions than the temperature field.

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Natural convection flow of a non-Newtonian power-law fluid from a slotted vertical surface with uniform surface heat flux

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes1054 ◽

2008 ◽

Vol 223 (3) ◽

pp. 637-642 ◽

Cited By ~ 2

Author(s):

R S R Gorla ◽

M A Hossain

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Power Law ◽

Vertical Surface ◽

Surface Heat ◽

Convection Flow ◽

Natural Convection Flow ◽

Boundary Layer Equations ◽

Power Law Index ◽

Type Power

In the present paper, the natural convection flow of an Ostwalde—de Waele type power-law non-Newtonian fluid past a uniformly heated vertical slotted surface has been investigated numerically. The equations governing the flow and heat transfer are reduced to local non-similarity form. The transformed boundary-layer equations are solved numerically using implicit finite-difference method for values of ξ in the interval [0, ∞]. Solutions for heat transfer rate obtained for the rigid surface compared well with those documented in the published literature. From the present analysis, it is observed that an increase in ξ leads to increasing the skin-friction as well as reduction in heat transfer at the surface. As the power-law index n increases, the friction factor as well as the surface heat transfer increases.

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Transient natural convection flow between vertical concentric cylinders heated/cooled asymmetrically

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650918758743 ◽

2018 ◽

Vol 232 (7) ◽

pp. 926-939 ◽

Cited By ~ 7

Author(s):

Basant K Jha ◽

Michael O Oni

Keyword(s):

Natural Convection ◽

Buoyancy Force ◽

Distribution Parameter ◽

Convection Flow ◽

Force Distribution ◽

Natural Convection Flow ◽

Transient Natural Convection ◽

Riemann Sum ◽

Concentric Cylinders ◽

The Impact

This paper investigates the impact of asymmetric heating or cooling of cylinder surfaces on transient natural convection flow in between vertical concentric cylinders. The outer surface of inner cylinder is assumed to be heated with temperature greater than the cooled inner surface of the outer cylinder. Closed form expressions are obtained by using the well-known Laplace transform technique to solve the governing partial differential equations in Laplace domain, whereas the Riemann-sum approximation is used to invert to time domain. Results show that the role of buoyancy force distribution parameter is to increase temperature, velocity, skin-friction and volume flow rate for both air and water. Further, reverse flow formation can be controlled by using suitable buoyancy force distribution parameter.

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An experimental study of the transition of natural convection flow adjacent to a vertical surface

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(74)90042-8 ◽

1974 ◽

Vol 17 (1) ◽

pp. 93-107 ◽

Cited By ~ 35

Author(s):

Francis Godaux ◽

Benjamin Gebhart

Keyword(s):

Experimental Study ◽

Natural Convection ◽

Vertical Surface ◽

Convection Flow ◽

Natural Convection Flow

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