Mechanical model of fixed-tube-sheet heat exchangers
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According to 7.4.1.3 of GB/T 151-2014, the mechanical model used in this calculation method treats the tube sheet as an axially symmetric structure. It is assumed that the tube sheets at both ends of the heat exchanger are made of the same material and have the same thickness; furthermore, for fixed-tube-sheet heat exchangers, the two tube sheets must also have identical boundary support conditions. May I ask, what do these identical boundary support conditions refer to? In \"Process Equipment Design,\" the support conditions of circular flat plates subjected to uniformly distributed loads are divided into fixed supports at the periphery and simply supported ends at the periphery. If I use an E-type tube sheet at one end and a b-type tube sheet at the other, do the two tube sheets still have the same boundary support conditions?
I believe that although both type E and type B tube sheets are fixed at the periphery, since type E also has to withstand flange bending moments, their boundary support conditions cannot be considered identical. If the same heat exchanger uses both e and b types of tube sheets, both tube sheets in a conventional design can adopt the e-type tube sheet thickness; only through stress analysis can different tube sheet thicknesses be determined.
So I will use a Type B tube sheet on one section and a Type E tube sheet on the other; the thickness of both tube sheets will be the same, namely the thickness calculated using the Type E tube sheet. Can we still use the method in GB/T 151-2014 for calculation?
I can calculate it this way, and the error is within an acceptable range.