Simulation and application study of VRV system in office building.

With excellent characteristics of good PLR, precise control, higher thermal comfort, flexible terminal unit control, good heat transfer efficiency, etc, VRV systems are growing rapidly in China in commercial market in recent years and even shares about 35% in 2013. It is noted however, most of the research is limited within the refrigeration system itself or no supported by field data. In this paper, one story office building is investigated, its annual energy consumption is 42.2 kWh/m2.a. Another important feature is that energy consumption of VRV system is of little relevance with building area. In order to give an insight into energy consumption of office building, VRV system and chiller & boiler system connecting with that office building are simulated during different operating schedules with software of Energyplus. Simulation results imply that energy consumption of VRV system is always higher than that of chiller & boiler system. When overtime working load increases from 0 to 40%, the energy consumption increase rate of VRV system is lower than that of chiller & boiler system. In this paper, occupant behaviour of energy saving factor a is addressed which used to describe the impact of running schedule and setting temperature to the energy consumption of VRV system. Its upper limit value is considered to be 0.38 via preliminary analysis.