Simulation Study Of Energy Saving Optimization For Cooling Water System Of Central Air Condition Based On TRNSYS

The energy consumption of central air-conditions takes large part in total energyconsumption of large public buildings. Because of the larger type selection, operation ofcentral air-condition at part load and lack of effective control, the central air-condition systemhas large energy saving potential. The cooling water system is one of important parts ofcentral air-condition system. The sensible control of cooling water system can bring energysaving effect to central air-condition system.The energy saving methods of central air-condition cooling water system in a hotel isstudied in this paper. And the simulator of cooling water system automatic control isestablished which can study the energy consumption in different control methods.By collecting the operating data of cold source, mathematical models of air conditionfacilities are built. The energy saving operation of cooling water system is analyzed. Theresults show that comparing to cooling water flow rate, air flow rate affect the coolingcapacity of cooling tower much more. Four cooling towers operating at part load can saveenergy comparing to three cooling towers operating at full load when the total water flow ratekeep constant and the cooling effect is the same. The simulation results show that it isunreasonable to neglect the effect of cooling water flow rate and air flow rate to COP. Theenergy of cooling water system can be saved when the system under variable cooling waterflow and air flow control. There will be larger energy conservation space when the load rateof chiller is low. It is needed to consider the weather conditions and working conditions ofchiller when the control method is selected.Based on the analysis above, the operating parameters optimization method of coolingwater system based on genetic algorithm is purposed. Under the premise of satisfying theoperation condition of central air condition system, this method optimize the motor frequencyof cooling water pumps and cooling tower fans based on weather conditions and operatingparameter of chiller. Under the control of this method, the energy of central air conditionsystem can be saved. The energy conservation effect of this optimization method is verifiedby simulator of cooling water system automatic control. The results show that energy savingproportions of operating parameters optimization method is12.4%which is larger than othercontrol method.