大型碟式太阳能聚光器网架缩模相似设计及数值模拟

Similarity design and numerical simulation of large dish solar energy concentrator grid scaled model

开展了25 k W大型碟式太阳能聚光器网架缩比模型相似准则分析并进行了相似设计,根据网架原型与缩比模型的静动力相似参数,建立了原型及缩比网架的有限元模型,通过对原型和缩比网架的力学特性数值模拟,揭示了不同工况下二者在位移、应力及自振特性方面的相似关系。结果表明,不同工况下缩比模型与原型的数值模拟结果误差均小于5%,二者在位移和应力分布及各阶振型上基本一致;网架基频频率相似误差较大,为进一步降低基频相似误差,缩比模型应增加构件侧向弯曲刚度,所作研究能够为后续网架模型的精确制作与模型试验提供参考。

The similarity criteria analysis and similar model design analysis for scaled model of 25 KW dish solar energy concentrator grid was launched. Finite element models of prototype and scaled grid were established based on the static and dynamic similarity parameters between prototype and scaled model. The similar relationships between the prototype and scaled model on displacement, stress and vibration characteristics in different conditions were revealed according to the mechanical properties numerical simulation between prototype and scaled grid. The results indicated that the mechanical numerical simulation error results between the scaled model and prototype were less than 5 percent. The displacement and stress distribution and vibration modes were basically the same. The similar fundamental frequency error of grid was larger. The scaled model should increase the lateral bending stiffness in order to reduce the fundamental frequency similar error. It can provide references to the accurate manufacture of following grid and model test.