Further Investigation To Improve The Control Of Aerodynamic Noise In Mechanical Ventilation Cooling Tower

In recent years,most of the newly built power plants are gas-fired power plants.In view of the heating requirements,the power plants cannot be too far away from the urban area.Therefore,the power plant uses a mechanically ventilated countercurrent wet cooling tower to release the heat of the gas generator set,which will bring a lot of noise to the surrounding residents.In this paper,after studying the theory of fluid and acoustics,the flow field and sound field of cooling tower are studied by numerical simulation,and the location of noise source is determined.On this basis,the corresponding optimization design scheme of noise reduction is put forward for noise source,and the relevant experimental verification is carried out.The main contents of this paper are as follows:(1)Research on the setting method to establish a geometric model cooling tower,meshing and boundary conditions of the policy and procedures,and numerical calculations apply to sound field characteristics of the cooling tower flow field method For the flow field steady-state simulation,use the RNG k-? combined with the broadband noise model to calculate the noise distribution;the transient is combined with the LES model and the FW-H acoustic analogy equation to analyze the sound field of the monitoring point,and master the overall research process of numerical simulation of aerodynamic noise of cooling tower.(2)Cooling tower noise optimization design exploration.According to the generation mechanism of the aerodynamic noise and the sounding part,the blade installation angle,the number of blades,the tip clearance and the rotational speed of the axial flow fan are taken as the research objects respectively,and the influence of relevant factors on the flow field and the sound field of the cooling tower is obtained,and according to each The characteristics of the elements propose improvements and lay the foundation for the later research.(3)Exploration of cooling tower noise optimization design.According to the generation mechanism of the aerodynamic noise and the sounding part,the blade installation angle,the number of blades,the tip clearance and the rotational speed of the axial flow fan are taken as the research objects respectively,and the influence of relevant factors on the flow field and the sound field of the cooling tower is obtained,and according to each The characteristics of the elements propose improvements and lay the foundation for the later research.(4)Simulation and experimental study of the optimization model.Design the noise optimization model.The noise reduction mechanism is studied by means of numerical simulation.The practicality of the control experiment is verified by the contrast experiment.The experimental results show that the new model can effectively reduce noise and prove that the simulation is credible.