Principle, design and operation strategy of cooling and heating complementary device for interior and perimeter zones of VAV air conditioning systems

In view of the simultaneous cooling and heating demands in the interior and perimeter zones of variable air volume (VAV) air conditioning systems in winter, this paper proposes to set up a cooling and heating complementary device for the interior and perimeter zones to obtain mixed benefits through active measures, which can balance the uneven cooling and heating between the interior and perimeter zones, achieve the purpose of cooling and heating complementary for the interior and perimeter zones, and reduce or avoid the energy-inefficient phenomenon of cooling and heating offset in the air conditioning zone. According to the principle of air conditioning load balance, the design, selection and operation strategy in different seasons of the device are defined. Through the design and selection, it is verified that the device can reduce the installed capacity of the terminal heating equipment or avoid installing the heating equipment in the perimeter zone, thus reducing the cost of the air conditioning system. The winter operation energy consumption of the comparison cases in different climate regions is simulated by the EnergyPlus software, and it is confirmed that the device can save the operation energy consumption and cost of the air conditioning system in winter. In addition to being used in VAV air conditioning systems, the device is also suitable for other air conditioning systems.