| The cooling tower used in air-conditioning system is mostly opened, that is to say, the cooling water could be polluted by directly contacting with the air which flows in the tower. The main part of a closed cooling tower is an evaporative cooler tube through which the heat exchange between cooling water and air are happened, therefore, the water quality will be guaranteed for recycling use due to its inside flow. Meanwhile, using water drenching fillers as a pre-cooling segment in spraying stage to reduce the temperature of spray water that contribute to decrease the area of coil. Whereas the reports about cooling performance and optimized design of combination of coils and WDF(water drenching fillers) are rarely appeared.According to the first-mentioned background, the performance research and optimize design of combination of tube and WDF is advanced. This article researches on get mathematical model solution, analysis influence factor of cooling performance and optimize design.Firstly, mathematic model of heat and mass transfer of CCCT (counter-flow closed cooling tower) is made due to their simplification of procedure which is based on the combination of theoretical analysis of WDF and tube and definition of constraints and boundary condition. That through the empirical formula calculates the heat and mass coefficient, and finally gets the solution of the mathematic model.Secondly, analyze the influence of counter-flow cooling tower operating parameters and configuration parameters on the cooling performance. The symbols of the cooling performance are outlet temperature of cooling water and heat and mass transfer coefficient. The configuration parameters include: the space between tubes, the inside diameter and arrangement form of coils. The operating parameters include: spray water flow rate, the air wet-bulb temperature, air flow rate and cooling water flow rate.Thirdly, visible contact surface is made by the MATLAB and C# that provide optimization toolbox and user-friendly visual programming environment for simplifying the complicate calculation procedures. That considers the synthesis of heat and mass transfer coefficient as the objective function, and climatic conditions, load and some conclusions got previously as the constraints condition calculates the optimized result such as area of heat-exchanger, distance between coils, spray water and air flow rate and height of WDF by Genetic Algorithm.Analytical and experimental results suggest that the thermal conductivity is the least influencing factor that could make impact on the heat transfer through the tube wall; as a result brass tube could be replaced, and effectiveness of CCCT will decrease by an excess use of WDF, which will be computational optimized by programming embedded in module selection software. Finally some new step of searching direction will be presented by the end of the paper. |
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