A Study On Hydraulic Characteristics And Optimization Control Of Air Conditioning Chilled Water System

In the actual operation process of the air conditioning system,problems such as uneven water distribution,small temperature difference between supply and return water,large equipment selection,and excessive equipment selection are often encountered.Therefore,when the system is operated according to the design conditions,it often causes a serious waste of energy.Under the energy development trend of promoting energy conservation and emission reduction,research on energy-saving optimization control of air-conditioning systems is particularly important.In this paper,the actual air conditioning system of a certain project is taken as the research object.The water distribution is unevenly distributed during the investigation and testing process.The control system has poor control effect and high system energy consumption.The energy-saving optimization of “Intelligent On-demand Supply” is proposed.Control strategies and build simulation platforms for simulation studies.The hydraulic characteristics simulation study shows that the hydraulic imbalance of the system is very serious,and some branch flow can't be satisfied.The control simulation of the system is further carried out by using the "Intelligent On-demand supply" optimization control strategy.The strategy mainly includes the end Feng Shui integrated control,the differential pressure differential frequency control and the minimum flow bypass control.The simulation results of energy-saving optimization control show that under the energy-saving optimization control mode,the system can adjust the chilled water flow in real time according to the indoor load to meet the indoor thermal comfort demand.In the whole air-conditioning season,the annual energy consumption of the pump in the existing operating mode is 44,823 kWh.Under the energy-saving optimization control mode,the annual energy consumption of the pump is 31,438 kWh,the energy saving is 13,340 kWh,and the energy saving rate of the whole air-conditioning season is 29.8%.Finally,the energy-saving optimization control of the actual system is upgraded,and the “Intelligent On-demand Supply” strategy is applied to the actual system.The actual system operation results show that the energy-saving optimization control mode can well maintain the indoor environment comfort.In the energy-saving optimization control mode,the energy saving rates of the chilled water system on the full load day and partial load day were 29.4% and 52.8%,respectively.The “Intelligent On-demand Supply” optimization control strategy has obvious advantages in system hydraulic regulation,meeting indoor thermal comfort and system energy saving.