EXPERIMENTAL STUDY OF DIFFERENCES OF SPEED PROFILES IN CONTRACTION CONE AND DIFFUSER SECTIONS ON WIND TUNNEL

Indonesia

Abstract

A fluid is a substance that can move when subjected to shear stress, it can be a liquid (incompressible) or a gas (compressible). The characteristics of compressible fluid flow are strongly influenced by the velocity (Mach number) and the shape of the cross-section through which the fluid passes. In this study, changes in the velocity profile of compressible fluid flow in an open subsonic Wind Tunnel (Ma<1) will be studied, and especially in parts that have a changed cross-sectional shape, namely the contraction cone and diffuser areas.To obtain changes in the velocity profile of the fluid flow, a pitot tube measuring instrument which is driven by a linear actuator manually is used at the points that are the focus of this study. In order to produce a fluid flow that is not random (laminar) Honeycomb is used. The results of the pressure measurement will be measured by a sensor connected to the pitot tube, then processed by Arduino. Based on the test results on contraction cones A, B, and C and diffusers D, E, and F, it was found that the highest average dynamic pressure is at the midpoint and the pressure will decrease when approaching the top wall but at diffuser F The pressure at the center point is low because it is facing the fan shaft.