Study On Optimizing The Heat Dissipation Layout Of Wind Turbine Nacelle Considering The Effect Of Multiple Heat Sources

With the increasing demand for wind power generation in modern society and the rapid development of wind power technology,the capacity of wind turbines is increasing,and the economic benefits are significantly improved.But at the same time,the heat generated by the unit is also increasing.The accumulated heat load will lead to the increase of the ambient temperature in the cabin.If the temperature rise in the cabin can not be effectively controlled,the excessive cabin temperature will not only increase the failure rate of the wind turbine,but also seriously threaten the operation safety of the wind turbine.The problem of heat dissipation in wind turbine cabin has become a bottleneck restricting the upgrading of unit capacity,which has attracted more and more attention of engineers and technicians.There are many cooling modes in the wind turbine nacelle,among which forced convection cooling system is the most widely used.This paper seeks to optimize the layout of the nacelle heat dissipation and the structural parameters of the heat dissipation system in order to enhance the cooling capacity of the nacelle.Firstly,the flow field in a typical wind turbine nacelle is simulated and analyzed by computer simulation technology.The flow path of cooling air entering the wind turbine nacelle through the intake is defined,and the parameters such as the velocity distribution of air distribution are obtained,which lays a foundation for the analysis of the temperature field in the nacelle.Secondly,the thermodynamic boundary conditions of the nacelle temperature field under rated power operation are obtained by calculating the calorific value of the main heat sources in the wind turbine nacelle.On this basis,the cabin temperature field with the "down-feed tail row" type heat dissipation layout is simulated and analyzed.Through the analysis of the temperature field in the wind turbine nacelle,it is clear that there are some problems in the nacelle studied in this paper,such as the serious uneven distribution of the temperature field,the serious accumulation of local thermal load and the low heat dissipation efficiency of the cooling system.In view of these problems,this paper studies the influence of the main heat sources on each other.It is clear that the influence of heat sources on each other's surface ambient temperature leads to the decrease of heat dissipation performance of heat sources,further aggravating the accumulation of heat loads and abnormal temperature rise of heat sources.In addition,the temperature field of gearbox and generator is simulated and analyzed when the ambient temperature of the wind turbine nacelle changes,and the temperature rise of heat source caused by ambient temperature rise of engine room is quantified.Finally,the airflow structure of the wind turbine nacelle is optimized from the aspects of the layout of heat dissipation,the position of intake/exhaust port,the size of intake port and the air speed of intake port,which improves the heat dissipation performance of the wind turbine nacelle in many aspects.