Improving the Energy Performance of HVAC Systems in Operating Theatres by Using Heat Recovery Devices

Abstract

Heating, ventilation and air conditioning (HVAC) systems in operating theaters use fully fresh air, and return air is not allowed to be mixed with the fresh air. Therefore, HVAC systems in operating theaters are inherently energy-inefficient. In this research, the impact of heat pipe heat exchanger (HPHX) as a heat recovery device on the performance of an existing HVAC system of an operating theater was examined. The existing HVAC system, Plant A, was redesigned by the added HPHX as Plant B and C and the most suitable design in terms of energy consumption level and provided air conditions was recommended for the system. A transient system simulation software (TRNSYS) was used for the simulation of the systems for a yearly operation of 8760 hours. Based on the results, the application of HPHX, Plant C configuration, could decrease the energy demand of the system and it is recommended to be implemented in the existing HVAC system. Moreover, it was shown that the HPHX integrated system improves the room and supply duct air conditions.

Keywords

• Energy consumption level; heating, ventilation and air conditioning (HVAC) systems; heat pipe heat exchanger (HPHX); operating theaters; TRNSYS.

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