Influence Of Underground Air Intake Device On The Performance Of Indirect Air Cooling Tower

With the introduction of the ’double carbon’ strategic policy,the pressure on energy conservation and emission reduction in the thermal power industry has suddenly increased.The new ’cooling tower’ using indirect air cooling technology can not only save a lot of water resources,but also have good heat exchange effects.An important manifestation of the green transformation of thermal power plants.However,the existence of ambient wind will affect the heat transfer performance of the radiator.How to eliminate or reduce the adverse effect of ambient wind on the radiator has become an important research topic in the thermal power field in recent years.Taking a 660 MW indirect air cooling tower as an example,this paper establishes the physical model of the indirect air cooling tower under the ambient wind condition,and analyzes the influence of the ambient wind on the flow field of the air cooling system and the heat transfer performance of the radiator under the wind speed of 0 ~ 20 m / s;In order to avoid the influence of ambient wind on the heat transfer performance of radiator,the underground air inlet device of air cooling tower is designed.The radiator is placed below the horizontal ground.The air flow field characteristics of underground air inlet indirect air cooling tower are numerically simulated,and the cooling air flow and heat transfer of radiator under different wind speeds and temperatures are obtained;The air inlet width,bottom diameter and air inlet angle of the underground air inlet device are optimized,and the best structural parameters of the underground air inlet device are obtained.The results show that the underground air inlet device can reduce the airflow velocity outside the tower,reduce the inlet pressure on the windward side,reduce the air flow,and prevent the occurrence of hot air penetration.Concentrating on the leeward side,the high temperature area at the air inlet of the radiator on the inner side of the tower and the leeward side disappears,effectively improving the heat exchange performance of the fan sections on the sidewind side and the leeward side.And the effect of different ambient temperature on the air flow and heat transfer performance of the radiator in the underground air inlet indirect air cooling tower is obtained.In the simulated different underground air inlet devices,increasing the width of the air inlet is beneficial to increase the air intake,but the excessive width of the air inlet will affect the heat transfer performance of the radiator under high wind conditions;increasing the diameter of the bottom surface can weaken the influence of the flow around the cylinder,The heat transfer performance of the fan section on the side wind side is significantly improved;at low wind speed,increasing the air inlet angle can increase the air circulation area of the air inlet,and improve the cooling air flow and heat exchange of the radiator.The analysis shows that the underground air inlet device with an air inlet width of 30 m,a bottom diameter of 500 m and an air inlet angle of 60° has the best effect on improving the heat transfer performance of the radiator.