kth_logo.gif

Licentiate seminar

Development of guide-vanes for expanding corners with application in wind-tunnel design


Defendant Main Advisor Extra Advisor Date
Björn Lindgren Arne Johansson 1999-04-30

Opponent
Lennart Löfdahl, CTH

Evaluation committee

Abstract

A new low speed wind tunnel has been designed and built at the Department of Mechanics, KTH, under the leadership of professor Arne Johansson. The length of the test section is 4 m and the cross section area is 0.5 x 0.75 m^2. The tunnel is powered by 15 kW to give a maximum speed of 48 m/s with a normalized mean total pressure variation of +-0.1% in the cross-stream plane of the test section. The wind tunnel is built with expanding corners equipped with guide vanes designed to give very small losses and good flow quality. Measurements of the total pressure loss coefficient behind the first corner showed that the use of expanding corners is a good option to obtain a compact tunnel circuit with a minimum need for diffusers. The total pressure loss for the tunnel circuit is 0.46 of the dynamic pressure in the test section at a flow speed of 46 m/s. A relatively low noise level is also achieved by use of acoustic damping material in the sections surrounding the fan.
[Download (1.5 Mb)]