Can Someone Explain "Bayonet" Exchangers To Me? 2

[Christine74]

I seen a few shell and tube heat exchangers that were of the "bayonet" configuration, meaning that the tube-side fluid sees two coaxial passes, with the second tube pass being a larger diameter tube that surrounds the tube of the first pass.

With all of the potential problems of such a design (difficult to assemble, vibration, etc.), why are these things used? It would appear that the only thing such a design would do would be to prevent the tube-side fluid from heating up or cooling down too quickly. What good is that?

Thanks,

-Christine

 

[EGT01]

Christine74,

I don't know what type or service where you have seen these used but they are quite popular for vaporizing liquid chlorine on the shell side. The following link indicates some of their design features...

http://www.rmarmstrong.com/products3.htm

 

[25362]

You'll find the pros and cons in The Chemical Engineering Guide to Heat Transfer Vol 1: Plant Principles (McGraw-Hill)