Applied Scientific Research

, Volume 42, Issue 2, pp 109–130 | Cite as

Core stratification effects on natural convection in inclined cavities

  • W. M. M. Schinkel
  • C. J. Hoogendoorn
Article

Abstract

A numerical and experimental study has been made on the flow and heat transfer in inclined air-filled cavities with aspect ratios 1–18 at Ra numbers from 2·104–5·105 and angles of inclination from 40 to 90°. Core stratification influences the flow. Due to this there arises a torque with two components depending on angle of inclination. On basis of the two torques the computed effects on flow and temperature fields can be explained. For the heat transfer a scaling law could be derived. Experimental data validate the numerical studies.

Keywords

Experimental Data Heat Transfer Convection Torque Experimental Study 

Nomenclature

A

Aspect ratio:H/D

D

Distance between hot and cold plate

g

Gravitational acceleration

Gr

Grashof number:g;(T H -T c )D 3/v 2

H

Distance between lower and upper side wall of cavity

k

Thermal conductivity air

l

Dimensionless length

Nu

Nusselt number αD/k

p

Dimensionless pressurePgβ(T H T c )D

P

Pressure

Ra

Raleigh number:g(T H T c )D 3a

T

Temperature

u

Dimensionless velocity:Uν/gβ(T H T c )D 2

U

Velocity componentx-direction

\(\tilde u\)

Scaled dimensionless velocity (sin ϕ)−1/2 u

v

Dimensionless velocity:Vν/gβ(T H T c )D 2

V

Velocity componenty-direction

x

Dimensionless coordinateX/D

X

Coordinate along hot plate and alongH

y

Dimensionless coordinateY/D

Y

Coordinate perpendicular to hot plate

\(\tilde y\)

Scaled dimensionless coordinate: (sin ϕ)1/4 y

Greek symbols

α

Heat transfer coefficient at hot plate

β

Thermal expansion coefficient

θ

Dimensionless temperature:T−T c /T H −T c

ϕ

Angle of inclination relative horizontal

ρ

Air density

σ

Torque

τ

Dimensionless temperature gradient alongX-coordinate at central point

ν

Air kinematic viscosity

ω

Torque proportionality factor: sin ϕ+τ cos ϕ

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Copyright information

© Martinus Nijhoff Publishers 1985

Authors and Affiliations

  • W. M. M. Schinkel
    • 1
  • C. J. Hoogendoorn
    • 1
  1. 1.Department of Applied PhysicsDelft University of TechnologyDelftThe Netherlands

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