Research On Performance Of Direct Steam Collecting Tube Under High Heat Flux

Solar thermal power generation is composed of several large blocks such as concentrating system,heat collecting system,heat storage system and power generation system.The concentrating system mainly considers the tracking of the mirror,mainly considering the accuracy of the tracking system reflected to the heat collecting tube,and The loss of light reflection process,and the performance of collector tube is the most important part of solar thermal power generation.We know that the sun’s rays always change at times,which leads to the uneven flow of heat flux on the collector tube,which in turn causes The bending deformation of the heat collecting tube reduces the life of the heat collecting tube.First,the heat collecting tube affects the heat transfer density and the direct convective heat transfer of the medium inside the tube.Secondly,due to the uneven heat flow density,the long-term use causes the heat collecting tube.The bending deformation further shortens the service life of the heat collecting tube.In severe cases,even an explosion may affect the life of the entire power station worker,which is unbearable for a high-cost power station.The research on the heat collecting tube is the main content of this paper..In this paper,the solar collector tube with water as the fluid medium under the action of high solar heat flux is taken as the reference object.The heat transfer performance,thermal stress and deformation of the collector tube under high heat flux density are simulated by Ansys fluent software.The numerical analysis shows how to reduce the equivalent stress and deformation of the collector tube.The main research contents of this paper include: Firstly,the process of water change at different high temperatures is divided into supercooling zone,two phase zone and superheat zone.Then create different physical models,mathematical models for three different regions.The curves of the equivalent stress and deformation of the collector tube along the axial,circumferential and radial directions are analyzed by simulating the flow rates of different fluids,different heat flux densities and different heat flow positions.For the complex two-phase zone,the curve of the equivalent stress and deformation of the collector wall along the circumferential,axial and radial directions of the collector tube is increased.Then,through different collector tube materials,the curve simulation diagrams of equivalent stress and deformation in different directions are analyzed.Finally,the above analysis is combined to summarize the parameters of the optimal collector tube.In this paper,the thermal stress and deformation of the collector tube under different heat flux,different flow rates,different heat flux positions,different heat transfer coefficients,different wall thicknesses,and different collector materials are analyzed.It provides a reference foundation for the optimal design of solar collector tubes.