Multiple Evaporator Systems

Past research efforts have investigated control methods for multiple evaporator systems. These studies typically investigate systems with three or fewer evaporators. However, systems with upwards of 10 evaporators are becoming feasible and are not uncommon in Europe and Asia [47]. Systems with a large number of evaporators such as this are referred to as variable

refrigerant flow (VRF) systems. There are numerous studies in literature which investigate the efficiency of these systems comparing them to water chiller loops [48].

One potential investigation could examine how the degree of coupling between the evaporators of a VRF system is influenced by the number of evaporators. Many studies have determined that there is strong coupling in systems with two or three evaporators. However,

there is no study which investigates the coupling between a large number of evaporators as that seen in VRF systems. Research may be completed to determine what scenarios a single-input single-output control structure is sufficient and when a multi-input multi-output framework needed to account for system coupling.

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