Measuring the Wall-shear Stress for Turbulent Flows Using the Micro-Pillar Shear-Stress Sensor MPS3

Yiou Liu (Autor)

Buch | Softcover

168 Seiten

2021
Dr. Hut (Verlag)
9783843946704 (ISBN)

Infos

For wall-bounded turbulent flows, knowledge of the mean and the fluctuating components of the wall-shear stress is of vital importance for the investigation of near-wall flow structures, which are responsible for the turbulent energy and momentum transfer. In this study, the wall-shear stress distribution in wall-bounded turbulent flows is experimentally investigated using the micro-pillar shear-stress sensor (MPS3). Firstly, the impact of a riblet-structured surface in a turbulent boundary layer is investigated. Secondly, extreme events occurring at the wall, including the wall-normal velocity spikes and backflow events, are detected and analyzed based on the measured wall-shear stress patterns in a turbulent channel flow. Thirdly, the wall-shear stress pattern at different streamwise positions along a sinusoidal side-wall of a turbulent channel flow is analyzed. The flow field is distinguished from that over a flat wall by a separation region at the downslope and a free-shear layer over the trough, whose effects become weaker at higher Reynolds numbers. In conclusion, this thesis proves the capability of the sensors to measure the wall-shear stress distribution for more complicated flow cases and for surfaces with slight curvatures. The results substantiate results from previous numerical studies and may facilitate a further understanding of the near-wall structures in turbulent flows.

Produkt-Details

• Erscheinungsdatum: 31.01.2021
• Reihe/Serie: Strömungsmechanik
• Verlagsort: München
• Sprache: englisch
• Maße: 148 x 210 mm
• Gewicht: 263 g
• Themenwelt: Naturwissenschaften ► Physik / Astronomie ► Strömungsmechanik
• Themenwelt: Technik
• Schlagworte: Measurement • Turbulence • Wall-Shear Stress
• ISBN-13: 9783843946704 / 9783843946704
• Zustand: Neuware