Optimization Design Of Closed Cooling Tower Based On Parameter Variation

Circulating water cooling technology is an important way to save water resources and protect the environment.As a modern cooling equipment,cooling tower is widely used in steel,brewing,construction,textile,medicine and other industries.The improvement of production technology in the new era has higher requirements on the cleanliness of cooling medium and the reliability of cooling performance.The closed cooling tower is a kind of cooling equipment with cleaner and longer service life than the open cooling tower.With its many advantages,it is more and more favored by users.Therefore,it is necessary to optimize the structure of closed cooling tower according to the characteristics of closed cooling tower and the theory of heat and mass transfer.The performance of closed cooling tower is affected by many parameters,such as the temperature of the environment,the cooling water,the water temperature at the inlet and outlet,the heat transfer area,the atmospheric pressure,etc.The heat transfer area is the core of the design and manufacture of closed cooling tower.Therefore,the author further improves the mathematical model of heat transfer of closed cooling tower.Based on the fact of parameter change,the calculation program of heat transfer area is developed by MATLAB software.With the help of computer calculation,a more accurate analytical solution of heat transfer area can be obtained.In this process,the optimization method of structure and operation parameters of closed cooling tower is discussed.Taking 100 tons of circulating water per hour as an example,the heat transfer area of different wet bulb temperature in different regions is calculated and compared.It is found that although the analytical solution based on differential equation is of high precision,the solution process is very complex and is not easy for engineering and technical personnel to use.In view of the above problems,the author proposes an engineering solution to the heat transfer area of closed cooling tower by referring to the calculation of heat transfer area of evaporation type device.Then,the engineering solution is compared with the analytical solution.It is found that as long as the spray water temperature is reasonably selected according to the actual situation,the error can be within the allowable scope of the project,which is convenient for engineering technicians to use.Based on the above work,the author draws the model of industrial closed cooling tower by using the modeling software of CFD platform.Then,the running condition of closed cooling tower is simulated by FLUENT software.In closed cooling tower,circulating cooling water flows in coil,and coil is divided by structural grid,gas-liquid two-phase flow is outside the pipe.The spray water adopts DPM model of FLUENT software,and considers evaporation cooling process,which completely reduces the physical process of air flow in the tower.The results show that the cooling efficiency of closed cooling tower will be maintained by the appropriate air water ratio,spray density,pipe length and pipe spacing.The research results of this project have been applied in Shandong Taiwang cooling equipment Co.,Ltd.which has certain guiding significance for the structural optimization design and energy saving operation of closed cooling tower.Finally,the author puts forward three methods of heating,cooling and isothermal fog elimination based on theoretical analysis.Then,the typical structure of the closed cooling tower is given,which can effectively avoid the fog and make new contributions to the protection of the natural environment.