Wake-Induced Bypass Transition over a Flat Plate under Favorable and Adverse Pressure Gradients

• 作者: Eitaro Koyabu Tetsuhiro Tsukiji
• 来源期刊: 流量控制、测量及可视化(英文)
• 学科: 物理学
• 关键词: BOUNDARY Layer WAKE TRANSITION Pressure GRADIENT HOT-WIRE ANEMOMETRY
• 年，卷（期）: llkzcljkshyw_2013,（1）
• 页码范围: 13-19
• 页数: 7页
• 分类号: O3

摘要

The present study investigates wake-induced bypass transition of boundary layers on a flat plate subjected to favorable and adverse pressure gradients. The aim is to exploit unsteady effects in order to design an aft-loaded turbine blade without increasing the profile loss, as has been achieved for low pressure turbine blades. First of all, this fundamental study is to reveal the effect of the Strouhal number, which changed by using different numbers of wake generating bars. Detailed boundary layer measurements were conducted using two hot-wire probes. A passage-contouring device was employed to generate a pressure gradient on the test model, which was typical to that generated by an aft-loaded turbine blade. A spoked-wheel-type wake generator was used to create periodic wakes in front of the flat plate. It was found that the wake passage induces a significant change in the flow structure downstream of the flow acceleration region.