Example 1: Investigation of flow development in thermally-stratified turbulent boundary layers

The characteristics of turbulent boundary layers depend significantly on thermal stratification. One example is the differences observed in the atmospheric boundary layer characteristics during day and night time. The state-of-the-art thermal control system of the boundary layer wind tunnel at the WiRE laboratory is designed to produce thermal stability conditions similar to the atmospheric boundary layer using the Richardson number similarity.

In the current project, different inlet and floor temperature profiles will be set up corresponding to unstable, neutral, and stable atmospheric conditions, along with different free stream velocities. Using pitot static tube together with thermocouple sensors mean velocity and temperature measurements of the air will be carried out in the working section of the wind tunnel. The feasibility of optical flow measurements using particle-image velocimetry will be tested. In addition, heat flux sensors will be used to measure the heat flux at the tunnel floor.

The information will then be used to estimate the possible mean velocity profile, stability regimes and temperature gradients in the working section under a variety of temperature control settings and free stream velocities. In addition, the horizontal and lateral homogeneity of the flow will be investigated. Finally, power curve measurements of a miniature wind turbine immersed in different thermal stabilities will be carried out.

Your responsibilities

  • Carry out wind tunnel experiments in collaboration with Mr. Arslan Salim Dar
  • Perform a systematic data analysis on the acquired measurements
  • Provide a physical understanding of the turbulent flow development
  • Manage and curate large datasets

Learning outcomes

  • Hands-on experience with well established experimental techniques
  • Good understanding of turbulent boundary layers and atmospheric flows in relation to wind energy
  • Big data analysis and management
  • Development of academic and technical writing skills


For more information about the project and to be considered the position, please contact:

Prof. Fernando Porté-Agel
Email: [email protected]
GR B2 400 (Bâtiment GR)
Station 2
CH-1015 Lausanne