I encountered a conceptual issue that I’ve never seen before when performing thermal calculations for heat exchangers! I hope some expert will come and answer it
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This post was last edited by penryn on 2011-6-30 16:05. The number of main contractions that the fluid passes through in a cross-flow region; the effective number of contractions in a circular-notch area. What does this refer to?:)
Ask: the technical discussants; they can help you figure things out
Reply 1# penryn: Please provide some background info, owner – when did you encounter this? So that it can be discussed
Reply 4# tank528
Reply to 5# penryn: From the baffle diagram, the so-called number of effective contractions refers to the number of tube rows; this term seems a bit unconventional. The effective number of tube rows is an important structural parameter that is used in subsequent calculations of the heat transfer coefficient and pressure drop. I recommend referring to Liu Wei’s \"Process Calculation Manual for Heat Exchanger Equipment\"; in my opinion, it is the best book of its kind in China. Another option is the older book \"Heat Exchangers\" by Lansi Institute, or books in foreign languages. As for the “number of contractions,” just ignore it.
Reply to 6# tank528: I’m referring to the Comprehensive Book on Chemical Equipment Design from 1987 – Heat Exchangers:
Reply to 6# tank528: I have this book on heat exchange equipment. I want to refer to the programming in it; for the fixed tube sheet type, there are equations related to oil viscosity calculation, and I’m stuck.
This post was last edited by wiseboy on 2011-6-30 22:39. Solving “transcendental equations” is precisely where computers excel; you cannot use powerful computing techniques merely to deal with elementary problems. The calculation method does not believe in “transcendental equations”. That bit of “transcendence,” when it encounters computers, is as effortless as using a sharp knife to cut vegetables.
It is approximately equal to the number of tube rows between the baffle gap and the inner wall of the shell