两跨传热管在水中横向运动时的支承阻尼

SUPPORT DAMPING OF TWO-SPAN HEAT EXCHANGER TUBE DUE TO LATERAL MOTION IN WATER

换热器管子的挤压膜阻尼与中间支承的几何参数以及管子与中间支承之间的动态相互作用有关。为研究中间支承的几何参数对挤压膜阻尼的影响,作者在具有中间支承的两跨试验装置上作了较系统的实验研究。本文主要研究管子在支承中作横向运动时的挤压膜阻尼。实验研究表明:支承厚度、直径间隙等几何参数对挤压膜阻尼均有明显的影响,而管子相对于支承板上圆孔的偏心率也是一个很重要的影响因素。在分析实验结果的基础上,讨论了计算挤压膜阻尼的半经验公式。

Squeeze-film damping is related to support prameters and dynamic interaction between the tube and the support.Systematic experiments are carried out on a two-span tube with one nitermediate sup- port to investigate the effects of support parameters on squeeze-film damping.This paper studies only the support damping of two-span tube due to lateral motion.Experimental results show that sup-port thickness and diametral clearance have an apparent effect on the squeeze-film damping.Eccen-tricity of the tube within the tube support has a very important effect.A semi-empirical expression to formu- late squeeze-film damping is discussed in light of the analysis of experimental results.