管壳式换热器管束的约束条件对振动固有频率的影响

本文采用有限元方法,分析了管壳式换热器的换热管及管束的约束对其振动固有频率的影响。通过对比分析不同管板厚度下,单个换热管前三阶固有频率的变化特性,发现换热管的固有频率随着管板厚度的增加逐渐增加。分析了GB151-1999中给出的管束的振动特性,发现管束的固有频率在解析解频率附近范围内存在较多频率。因此,在计算换热管束振动特性时,为了获得较为精确的结果,采用有限元方法计算是有必要的。

The Influence of the Shell and Tube Exchanger Tube Array Boundary Condition on Its Natural Vibration Frequencies

With finite element analysis,the natural frequency of the tube and tube array in shell and tube exchanger is obtained,and the influence of the boundary condition is analyzed.The first three orders of frequencies of a single tube constrained by tube sheet with different thickness are compared.It is found that the natural frequencies of tube increase as the increase of tube sheet thickness.The tube array in the GB151-1999 example is studied by finite element method.Several frequencies of the tube array are found around the analytical frequencies.As a result,in order to obtain more accurate result of the natural frequencies of tube array,it is necessary to analyze with finite element method.