Structural Design Of A New Type Of Closed Cooling Tower For Industrial Use Suitable For Dry And Wet Operation

The industrial circulating cooling water system is a common and important public dissipative system,which predominantly operates in whole year.The wet-dry compound type closed cooling tower with the multi-operating condition,as the industrial cooling tower,can realize the water and energy conservation by switching the operational mode according to the meteorological conditions.The wet-dry type cooling tower consists of the finned tube and plain tube.The cooling tower researched in this thesis is composed of two groups of finned tube heat exchangers which are connected in series side by side.The area ratio of the two groups of heat exchangers is optimized on the basis of the operating conditions,and the operational mode is switched in accordance with the meteorological conditions.The heat transfer model of cooling tower is established based on the theory of heat and mass transfer and heat transfer,and the accuracy of the model is verified.The structural and operational parameters are optimized and the influence of those parameters on the outlet temperature of cooling water is analyzed,and the structural and operational parameters of the cooling tower are determined.The area ration of the two groups of heat exchangers of the cooling tower is optimized,and an analysis on the influence of the water feeding pattern on the cooling performance is conducted.The scheme for the area ratio of cooling tower suitable for each city is designed by inputting the weather parameters of various representative cities into the procedure.A mathematical model is established for the parameter status of mixed air at the outlet section of cooling tower,and the computer program is used to calculate and establish the visual window.The scheme for the opening of spray water is analyzed.The research shows that when the area on both sides of the cooling water is different,the cooling water entering from the side with smaller is more beneficial to the cooling performance.And when the area on both sides of the cooling tower is equal and is insufficient to achieve the expected cooling performance,a better cooling performance can be realized by firstly opening the spray device at the water outlet side.The climatic conditions in different cities are calculated,and the result indicates that the energy consumption of water pump is the least when the area ratio of 1:1 is provided for the cooling tower.The state parameters of outlet air of cooling water are calculated,and the performance of fog dispersal of cooling water is analyzed.In the end,a further research direction is discussed briefly.