塔式太阳能电站集热管非均匀受热特性研究

摘要

塔式太阳能电站吸热器中的集热管是光热转换的核心组件。集热管面向镜场的半圆周受热，且热流密度沿圆周和轴向不断变化，背向镜场的半圆周绝热，同时集热管内水-蒸汽工质的沸腾流动换热尤为复杂，研究其受热特性有助于深入了解塔式电站吸热器集热管的整体性能。为此，建立了轴向和周向不均匀热流边界条件下水-蒸汽集热管内的数值模型。基于 Fluent平台，计算三维、非稳态的汽液两相流动，通过模拟分析呈现了管内的汽液两相流动特性，同时揭示了在这种极不均匀热流条件下，集热管的温度分布规律及其传热特性。%Heat collector pipe in receiver of solar thermal power tower plants is a kernel unit to convert solar energy into thermal energy.Only the semi-circumference facing the heliostat field receives heat flux,while the other semi-circumference depart from the heliostat field is adiabatic.What's more,the heat transfer of boiling flow in the pipe with the water-vapor as the working fluid is especially complex.So the understand-ing of the heat transfer characteristics in it is significant and important.Through Fluent software,numeri-cal model of the water-vapor tube under uneven heat flux boundary with semi-circumference heated and the other semi-circumference adiabatic was established.The three-dimensional and unsteady water-vapor two-phase flow was numerically simulated.So,flow characteristics of the two-phase flow were obtained,and temperature distribution and heat transfer characteristics of the tube under uneven heat flux were revealed.