槽式太阳能双工质回路热发电系统能量分析及(火用)分析

摘要

为了解槽式太阳能热发电系统中各热力设备的热力完善性及过程的不可逆程度,本文以热力学第一及第二定律为基础,建立了槽式太阳能双工质回路热发电系统集热器子系统、透平发电子系统及凝汽器子系统的热平衡和火用平衡数学模型,并结合SEGS一Ⅵ的设计参数,计算得到了系统各部分热效率与(火用)效率,从而揭示了系统的(火用)损分布及其大小.结果表明:整个系统的热损失率为78.36％,其中热损最多的部位是凝汽器,占总辐射能的33.33％；整个系统的(火用)损失率为77.2％,其中集热场的(火用)损最多,占总太阳辐射(火用)的67.16％.此分析结果将为槽式热发电系统的改进以及效率的进一步提高提供依据.%The aim is to determine the thermodynamic integrity and irreversibility at all equipments in a solar thermal power generation system. Based on the first and second thermodynamic law, the exergy and thermal conservative e-quations of collector, turbine power generation and condenser subsystem of a trough solar thermal power generation using two medium circuit system are established. Combined with SEGS-VI design parameters, the thermal and exergy efficiency in each part of subsystems is calculated, and the distribution and value of exergy loss is revealed. The results show that the heat loss rate in the whole system is 78. 36%. The largest heat loss occurs in the condenser and it equals 33. 33% of the whole energy. Besides, the exergy loss ofrnsystem is 77. 2%. The largest exergy loss occurs in collector field and it equals 67.16% of total solar radiant exergy. The results can make contribution for the improvement of the trough solar thermal power generation.