基于APDL的碟式太阳能聚光器网架模态分析与结构优化

Modal analysis and structure optimization of dish solar concentrator grid based on APDL

为避免碟式太阳能聚光器网架与外界激励发生共振,需研究其振动特性,并通过结构改进以提高聚光器网架的刚度。本文运用APDL语言建立25kW碟式太阳能聚光器网架的几何模型和有限元模型,并对其进行模态分析,得到聚光器网架前十阶固有频率和固有振型。根据模态分析结果,针对聚光器网架振动特性和危险区域,对聚光器网架结构提出改进方案,并对改进的结构进行模态分析。研究结果表明:聚光器网架的轮廓边缘和缺口处是其振动的危险区域;桁架前端部分的刚度对聚光器网架的整体振动特性有很大影响;优化后的聚光器网架最小固有频率为10.475Hz,比改进前提高3.637 2Hz,明显改善聚光器网架的结构刚度和振动特性。

In order to avoid the resonance of dish solar concentrator grid and outside loads,we need to study its vibration characteristics and improve stiffness of concentrator grid by structure optimization.The paper established geometric model and finite element model of the 25 kW dish solar concentrator grid and conducted modal analysis by APDL.According to the results of modal analysis,the paper provides optimization proposal for concentrator on the basis of vibration characteristics and dangerous areas of concentrator grid,and conducts model analysis for improved structure.The results show that the dangerous areas of concentrator grid are contour edge and gaps;the stiffness of truss front section has a great influence on vibration characteristics of concentrator grid;the minimum natural frequency of improved structure is 10.475 Hz and increased 3.637 2Hz than before,the improved structure improves the stiffness and vibration characteristics of concentrator grid.