A Study of Wind Tunnel Wall Inerference Corection for 3 Dimensional Bluff Bodies

2014 Fiscal Year Final Research Report

• Project/Area Number: 22560184
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Tohoku University
• Principal Investigator: SAWADA HIDEO 東北大学, 流体科学研究所, 研究支援者 (30344245)
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 風洞壁干渉 / 阻塞効果 / 鈍頭物体 / 抵抗 / 磁力支持天秤装置

Outline of Final Research Achievements

Blockage effects for bluff bodies were examined using a magnetic suspension and balance system which has no support interference. Cylinder models of fineness ratio 4 were tested of which the blockage ratio of the smallest model was 0.44%. From the obtained results, there is a linear relation between the ratio and the drag coefficient if the ratio is less than 3.14%. Although the models of less than the ratio of 1.97% were not tested in case of fineness ratio 2, the similar tendency was observed in the tested blockage ratio range as in case of the fineness ratio 4. Total blockage correction for the model is the sum of the corrections for a streamlined body and for a bluff body if the separated flow at the leading edge reattaches to the model surface.
In addition, three scale models on ground with a large lift coefficient were tested. Existing blockage effect evaluation methods could not estimate corrections correctly.

Free Research Field

流体工学