Numerical Investigation on Air Mixer Performance for a Closed Loop Indoor Unit Test
Air mixer design for residential indoor air conditioning unit tests is explored with the assistance of computational fluid dynamics for a closed loop indoor unit test configuration. This test setup does not require a dedicated psychrometric test room, and air coming out of an indoor unit is circulated in a closed loop. The key design requirement for this approach is achieving desired uniform temperature distribution in returning air. The mixing performance of a conventional louver baffle and a cyclone type mixers is compared in this study. It is found that mixing performance can be varied as temperature measurement grids and the measurement may not represent the actual bulk air temperature. Although the considered louver baffle type has better mixing capability than the cyclone type in simulated conditions, an improved mixer design with a carefully arranged sensor grid is still needed to meet the industry standard and represent bulk air status.
Keywords: air mixer, cyclone, louvered baffle, CFD, sensor grid