Study On Design And Optimization Of Two-stage Solar Power Tower Cavity-receiver Generation System

With the Energy structure adjustment,the proportion of clean energy increases,solar thermal power generation has developed in recent years.A new type of two-stage solar power tower cavity-receiver was designed and a calculation model of radiation,convection and flow under the Gaussian heat flux was established so as to determine the piping layout and geometries in the receiver Iand receiver II and obtain the heat flux distribution in different positions.Then the main parameters about working fluid temperature,steam quality,wall temperature along the typical pipes and pressure drop were specified according to the heat transfer and flow characteristics of two-phase flow.Meanwhile,aseries of systematic design process was promoted and analysis on thermal performance of the two receivers was conducted.Results showed that this type of two-stage cavity-receiver can minimize the size and reduce the mean temperature of receiver I while raise the average heat flux,thus increase the thermal efficiency of the two receivers;besides,the multiple pass layout of coiled pipe headercan make a more uniform distribution of the outlet parameters,preventing severe problems like overheating.To further improve the two-phase flow characteristics inside the header during the heating process,based on the distribution of the flute-distributor proposed by the patent,CFD numerical simulation was conducted to analyse the distribution of thethe header with and without flute-distributor,comparing with the volume fraction,velocity field and other factors.It turned out that the flute-distributor will make a redistribution of the water-steam two-phase flow inside the headers,improving the distribution of it,which will have something meaningful to the solar power receiver with water-steam as heat transfer medium.