摘要
选取典型的多层软硬泡耦合内绝热单元结构作为研究对象,基于Workbench软件,采用有限元方法计算单元内部服役过程中的应力和位移形变,并对结构进行优化。结果表明,在相同尺度下,传统工艺中采用的方形夹层结构四角位置易形成应力集中,局部最大应力超过1. 6 MPa;而改为圆形夹层外缘则无明显的应力集中区。圆形夹层直径增大,最大应力值上升,直径大于250 mm时变化显著;夹层厚度的增大,最大应力值降低。夹层型式对最大形变量影响不明显。当采用圆形夹层结构型式,直径为250 mm、厚度为10 mm时,最大应力值约为0. 85 MPa,绝热单元的安全系数大致上升至1. 2。相较于传统工艺,增加了单元寿命,并尽可能减小了柔性泡沫填充对绝热及单元刚度的影响,可认为是一种理想结构。该模拟计算方法对聚氨酯泡沫塑料绝热产品工艺设计具有一定的参考意义。
In this paper, a typical rigid polyurethane （PUR） insulation cell with three layers consist of horny and soft foam was studied. Finite element method （FEM） was used to calculate the stress and deformation of the insulation cell under liquid nitrogen temperature condition based on Workbench. The cell structure was optimized based on the calculation. It was shown that the max stress was located in the interlayer. For the traditional cells with square interlayer, stress concentration would be formed near the corners. The max mises-stress was over 1.6 MPa. For the cells with round interlayer, no notable stress concentration was formed. The max stress in the cell rose with the diameter of round interlayer. The trend became more obvious when the diameter was longer than 250 mm. Besides, the max Mises-stress decreased when the thickness of interlayer increased. For the cells with round interlayer, when the diameter was 250 mm and the thickness was 10 mm, the max Mises-stress was 0. 85 MPa approximately. The safety factor was about 1.2. Compared with the traditional cells, the new structure could increase the service life of the cell while would bring acceptable damage to the insulating and rigidity due to the soft foam, which could be considered as an optimal design. The calculating method could be helpful for the designing of the PUR insulating productions.
作者
王翰林
刘清念
周翔
姜帅
WANG Han-lin, LIU Qing-nian, THOU Xiang, JIANG Shuai(Center of Numerical Manufacture Technology Research, Aerospace Research Institute of Materials ＆ Processing Technology, Beijing 100071, China)
出处
《塑料工业》
CAS
CSCD
北大核心
2018年第10期123-126,139,共5页
China Plastics Industry
关键词
聚氨酯泡沫
绝热单元
有限元
夹层几何结构
Rigid Polyurethane Foam
Insulation Cell
Finite Element Method
Structure of the Interlayer
