Boundary Layer Manipulation via Blowing and Suction: Numerical Simulation and Experimental Development and Validation of Soap Film Technique

  • Hussain Alshaikh Hassan

Student thesis: Master's Thesis

Abstract

This work deals with a passive control of a low Reynolds boundary layer of flow past a slitted cylinder oriented at different angles (α). It tackles the problem both numerically and experimentally. First, the numerical simulations were conducted using ANSYS fluent 17.2 and validated using results from the literature. The results indicate that the lift (CL) and drag (CD) coefficients are significantly affected at different slit angles. The CD is affected substantially when α=0, while CL is affected when the slit is oriented at α=π/6. The velocity fields resulting from the numerical simulations are projected on the Proper Orthogonal Decomposition (POD) basis. This analyzing method allows the identification of the main spatio-temporal components of the flow field calculated at the different slit orientations. Secondly, quasi-two-dimensional flow visualization experiments were conducted using soap film tunnel and compared with the numerical simulation results. The setup and procedure of the experiments was presented in detail. Furthermore, the passive blowing and suction flow was visualized inside the slit when α ≥ π/3. Three types of blowing and suction flows were observed, namely Equal Simultaneous, Unequal Simultaneous, and Alternating blowing and suction.
Date of AwardDec 2021
Original languageAmerican English

Keywords

  • This work deals with a passive control of a low Reynolds boundary layer of flow past a slitted cylinder oriented at different angles (α). It tackles the problem both numerically and experimentally. First
  • the numerical simulations were conducted using ANSYS fluent 17.2 and validated using results from the literature. The results indicate that the lift (CL) and drag (CD) coefficients are significantly affected at different slit angles. The CD is affected substantially when α=0
  • while CL is affected when the slit is oriented at α=Ï€/6. The velocity fields resulting from the numerical simulations are projected on the Proper Orthogonal Decomposition (POD) basis. This analyzing method allows the identification of the main spatio-temporal components of the flow field calculated at the different slit orientations. Secondly
  • quasi-two-dimensional flow visualization experiments were conducted using soap film tunnel and compared with the numerical simulation results. The setup and procedure of the experiments was presented in detail. Furthermore
  • the passive blowing and suction flow was visualized inside the slit when α ≥ Ï€/3. Three types of blowing and suction flows were observed
  • namely Equal Simultaneous
  • Unequal Simultaneous
  • and Alternating blowing and suction.

Cite this

'