A dynamic mathematical model of a direct expansion (DX) water-cooled air-conditioning plant

A dynamic mathematical model for a direct expansion water-cooled air-condit ioning plant typical to many actual installations in buildings has been dev eloped. The system components modelled are a compressor, a thermostatic exp ansion valve, a water cooled condenser and a direct expansion evaporator wh ich is also the cooling and dehumidifying coil in the air side. The evapora tor (cooling coil) model consists of a novel set of equations which can dis tinguish between two-phase superheated and refrigerant region in the refrig erant side, and between dry and wet cooling of an air handling process in t he air side. The model has been validated using the experimental data colle cted from the plant, and was separately reported. (C) 2000 Elsevier Science Ltd. All rights reserved.