| With the continuous breakthrough to technical bottlenecks,solar thermal electric power generation has set off a wave of international energy investment and construction.Among them,the solar thermal power tower technology has the advantages of high concentration ratio,high heat collection temperature,low heat loss,short heat transfer path,and high system comprehensive efficiency,and is the most ideal large-scale power generation method.Heliostat is an important part of solar power tower plant.Long-term dust accumulation will reduce the specular reflectivity,which will reduce the heat collection efficiency of the power plant and cause a serious energy loss.In order to maintain a high power generation efficiency,the effective solution is to clean the heliostats irregularly.Aiming at the increasingly serious problem of ash accumulation in photothermal power station,this dissertation researched the effect of dust on the reflectivity of tower heliostats.At the same time,a mirror-cleaning device for brush cleaning is proposed,and its mechanical properties are analyzed.The main work contents are as follows:(1)On the basis of understanding the structure and working principle of heliostats,the characteristics and properties of dust deposition,the mechanism of ash deposition affecting the reflectivity of heliostats was studied,and the ash deposition time and the ash density were measured by field experiments.Based on the experimental results,a mathematical model for the variation of reflectivity with time and density of ash deposition is established..(2)Taking DunHuang's 10 MW molten salt tower power plant as the research object,this chapter analyzed the dust removal function requirements according to the size and layout characteristics of heliostats,and proposed the overall design plan mainly including car body selection,manipulator structure design and cleaning mechanism design.The physical model of each component was built with SolidWorks software and integrated.(3)Based on the knowledge of theoretical mechanics,the maximum quality of the cleaning mechanism that can be allowed by the dust removal device can be obtained.Then the Ansys finite element analysis software is used to analyze the static characteristics of the mechanical arm structure,and the deformation and strain of the main components are obtained,which verified that the strength meets the requirements.(4)The kinematics and dynamics model of the dust removal device was established,and the motion process of the dust removal device was simulated by Adams software.The simulation results show that the design technology is feasible and the structure is reasonable.The dynamic parameters of the main drive components in the dust removal device are obtained by extracting the simulation results.The adjustable working range of the ash mechanism lays the foundation for physical manufacturing.The research in this dissertationr provides a good reference for the design of the cleaning products of the heliostat,the solution of the dust deposition problem of the solar thermal power plant in China,and the improvement of the efficiency of the solar tower power plant,which has a certain practical value in engineering. |
PDF Full Text Request