A study of air flow inside an air conditioning unit

The air conditioning system filters and regulates both temperature and humidity of the air supply to a telephone exchange. The system is comprised of a cooling unit which feeds two direct expansion V-configured finned coils. If the exchangers are to function properly, the air supply must be homogeneous, despite the apparently unfavourably assembly characteristics. Conventional velocity measurement methods are incapable of assessing this homogeneity. Two special techniques have therefore been used: laser tomography; and numerical simulation. Both investigation methods show a certain heterogeneity of the air distribution at the intake to the coils. A modified configuration was examined by digital simulation with a view to correcting the heterogeneities found in situ. The results of the study demonstrate how calculations may be used in the design and optimization of this type of installation