| 12| Verticle Cavities

Veritcle cavities (when τ = 90o)

For vertical cavities the temperature the temperature gradient occurs horizontally across the cavity, between two opposing walls. Lakes are examples of vertical cavities.

If RaL < 103 – The Nusselt number is equal to 1.

If RaL > 103 – The Nusselt Number is varies depending on the aspect ratio of the cavity. Consult sections 9.50 – 9.53 in the textbook to find the equations to calculate Nusselt Numbers for different cavity geometries. These will be on the Formula Sheet!