Analysis of Flows in a Heater Unit of an Automobile Air Conditioning System.

Abstract

Facilitating cool-hot air mixing inside the heater unit is one of important factors when considering the design of air conditioning systems. In order to produce efficient mixing in the limited space inside the heater unit, conventional guides are provided to control mixing. Because of the difficulties of detailed analysis of air flow inside the heater unit, the shapes and installation positions of these guides were determined empirically. The development of experimental flow analysis utilizing the latest image processing technology and computer-aided numerical analysis contribute remarkably to the design of air conditioning system based upon qualitative and quantitative analysis of actual flow phenomena. In this report, laser-assisted flow visualization and the velocity distribution measuring technique using the speckle method are applied to an experimental analysis of guide effects to cool-hot air mixing in a heater unit model. Additionally, the results of 3-dimensional numerical analysis of the heater unit air flow using standard software are compared with the experimental ones to verify the validity of the method as an effective tool for the heater unit air flow analysis.