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


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.


Experimental Data Heat Transfer Convection Torque Experimental Study 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Aspect ratio:H/D


Distance between hot and cold plate


Gravitational acceleration


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


Distance between lower and upper side wall of cavity


Thermal conductivity air


Dimensionless length


Nusselt number αD/k


Dimensionless pressurePgβ(T H T c )D




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




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


Velocity componentx-direction

\(\tilde u\)

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


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


Velocity componenty-direction


Dimensionless coordinateX/D


Coordinate along hot plate and alongH


Dimensionless coordinateY/D


Coordinate perpendicular to hot plate

\(\tilde y\)

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

Greek symbols


Heat transfer coefficient at hot plate


Thermal expansion coefficient


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


Angle of inclination relative horizontal


Air density




Dimensionless temperature gradient alongX-coordinate at central point


Air kinematic viscosity


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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