Abstract
M.Ing.
The goal of the project was to stimulate aspects of the atmospheric boundary layer. As a result of the complexity of the derived models, it was decided to rather do an experiment on turbulent Couette flow to simulate. some aspects of the atmospheric boundary layer.
A Couette flow channel with a maximum wall speed of 1 m/s was built.
Experiments were done at two Reynolds numbers, l600 and 2500, corresponding to a channel height of 0.06 m and belt speeds of 0.4 mI and 0.58 m/s, respectively.
The Coutte channel has the facility that the supper stationary wall can be heated or cooled. Experiments were carried out with positive and negative temperature gradients for both the Reynolds numbers giving the following results.
By heating the top wall a stratified flow results which leads to no mixing of the flow properties. This phenomena is analogous to night time conditions in the atmosphere, when layers at different temperatures form a layered structure with little mixing between layers.