Design and operation optimization of an air conditioning system through simulation: an hourby- hour simulation study

In the present research, performance validation of a Heating, Ventilation, and Air Conditioning (HVAC) system operating in a library building was conducted. The operating HVAC system was studied in terms of the provided indoor air conditions and energy consumption level. The fieldwork measurements showed that the HVAC system is not capable of providing the desired indoor air conditions based on the ASHRAE standards. Therefore, two deciding design and operating parameters namely, chilled water cooling coil number of rows and chilled water temperate were investigated to achieve possible improvement in the system performance. For this purpose, different numbers of rows for cooling coil design at different chilled water temperatures were examined. TRNSYS software was employed to investigate the hourly effect of the variables on the system for a whole year of operation. Based on the simulation results, the provided indoor air conditions were appropriate and within the comfort area with the two-row configuration cooling coil. However, the energy performance of the system indicated that the two-row configuration with 10 C  chilled water temperature was superior in terms of energy consumption, and could provide the desired indoor air conditions, thus it was recommended to be implemented in the existing system.