Indian Journal of Science and Technology

Abstract

Objectives: This paper elucidate the entire procedure to design an open circuit subsonic wind tunnel which will be used to study the wind effect on the different prototypes of structural elements. Method: The existing guidelines and findings of the previous research works were followed for design calculation of different parts of the wind tunnel. Three design trials have been performed so as to achieve a velocity of 25 m/s at the test section. The final trial has been discussed in the body of the paper. Findings: The design includes a square test section of side 500 mm, to accommodate the model and required instrumentation in it, for force and pressure measurement. A straight section before the test chamber is provided to allow the output of contraction section to stabilize before it reaches the test section. Instead of using a curved wall shape a straight contraction profile with larger contraction length is used. The diffuser extends from the test section and its cross section changes from a square test section to an octagon of 311 mm side. The pressure drop and power required for the designed wind tunnel are calculated and tunnel performance curve is plotted. Application: The design being purely empirical, it requires computational validation before commencement of the construction of the wind tunnel. The investigators have actually made an attempt to design the same in the existing setup, which may be useful for different research purpose. 
Keywords: Design of Open Circuit Wind Tunnel, Loss in Contraction Section, Power Requirement, Pressure Drop in Diffuser, Stilting Section, Tunnel Performance Curve