The Study On The Power Plant's Cold-end System And The Heat Transfer Performance Of The Cooling Tower

With the lack of energy and the increase of competition, it is more and more important for power plant to decrease coal consumption. In this paper, steam turbine cold end system is analysised, and it is focused on one of the important equipment of cold end system - cooling towers, improving the system's efficiency.In this paper, unit power plant DCS system is used for collecting data, the MATLAB is used to carry out principal component analysis, it is a way to reduce the various of the multi-factors of the steam cold end system, and ultimately to find three main components which could replace the original process variables; based on this, the turbine efficiency is on the linear regression; at last using a new evaluation system to do its comprehensive assessment. The results show that the cooling tower, that's performance is very important for the economic of the cold end system.The natural draught wet cooling tower (NDWCT) is analyzed. The mathematical model is established, and the one-dimension calculation of cooling tower is realized through Program, which could be used to evaluate the Performance of cooling towers. The environmental factors (dry-bulb temperature, humidity, etc.) and load factors (water temperature, heat load) is analysised on the influence of the efficiency of cooling towers and the performance of the fillers. For example of conditions in the text , When the humidity from 30% to 40%, efficiency is 0.6%, when the humidity from 60% to 70%, efficiency is 1.2%; and through the orthogonal test, it can be studied that the relationship between the variables.With the help of the test-bed of the cooling tower . It is submitted the relationship between the three parameters(fill height,the kinds of the fills and the distance between the nozzles and the fills) and the efficiency, The experimental results show that the distance between the nozzles and the fill is the most important parameter; and the empirical formulas of three common fills'(a circular wave, two-way wave, S wave) cooling number and volumetric mass transfer coefficient are fit.In this paper, the results of the study provides a theoretical basis for optimizing the operation of cold-end system ,and it is also a guide for improving the efficiency of cooling towers.