Application of CFD Simulations for Locating Outdoor Units on High Rise Tower

Abstract

The efficiency of an air conditioning system depends on the ability of ODU (Outdoor Unit) to deliver the required air flow rate that is needed for cooling the refrigerant. The case described in this paper involves solving an actual case wherein the occupants of a high rise building were facing an issue with ineffective cooling from their air conditioning system. The issue was traced back to ODUs (Outdoor Units) which were not able to provide sufficient air flow rate since it was located facing high winds. Different ODUs (Outdoor Units) were simulated for their efficiency under known conditions to arrive at the most suitable unit to provide sufficient air flow. CFD simulations were used to locate an appropriate location for the placement of ODUs. Focus during analysis of results was on the pressure distribution around the candidate ODU location. The suction and exhaust side of the ODU was identified and pressure difference between the exhaust and suction surface was quantified. By comparing the additional pressure head against design pressure head, magnitude of deterioration of fan performance was understood and these results helped in locating the ideal location for placing the ODUs (Outdoor Units).