Abstract
Installation of Proportional-integral-derivative (PID) controllers in air conditioners regulates the hot/cold fluid flow in hot/cold coils, and consequently, maintenance, energy consumption and initial costs are lowered due to reduced coil capacity. In this research, the thermodynamic analysis of an air handling unit was investigated. The thermodynamic energy equations for AHU were developed in TRNSYS software. The temperature and humidity of the ambient air were incorporated into the software. Then, by defining the characteristics of heating and cooling coils, the air handling unit was simulated. To adjust humidity a heating coil along with several differential controllers were installed prior to the supply air duct. The simulation results showed that the air handling unit can provide suitable thermodynamic conditions in the interior space (22 °C and 55%). To provide ventilation conditions, AHU consumed 602 kWh/m2 per year. Due to the thermodynamic conditions inside the building, suitable conditions were provided for the air conditioner to use heat recovery and it is found that energy utilization in AHU coils dropped by 43.2%. Moreover, PCM was added to the building in two locations, the innermost layer and the outermost one. While the building took advantage of heat recovery, PCM in the outermost layer still managed to reduce AHU power utilization. However, due to the phase change temperature and the indoor temperature, if PCM is installed in the innermost layer, its performance will be slightly better.
•Introducing a new PID controller to control the addition of PCM.•Effects of PCM in the building with ventilation heat recovery installation.•Reduce the energy demand of the developed cooling system.