Does anyone have any good articles they could send me on vessel jacket heat transfer (dimple, half-jacket, conventional, etc).

RJB, I do not have any articles about what you are asking about, but the major differences between the three types of jackets are 1) Surface Area and 2) Turbulence within the jacket and 3) the amount of "dead flow" within each of the three types of systems.

While Dimple and conventional (which I believe you mean tank inside of tank construction/ball valve), you have maximized your heating surface area.  You have better turbulence with dimple obviously and less of a chance of dead flow.  

With Half-Pipe jackets, you have no chance of dead flow areas, but you limit your heating surface area because you need space between the welds.  This is a very crude way to jacket a tank and I would not recommend it to anyone.

So, of the three, Dimple jacketing is the best method in my opinion.

If you are looking for another type of jacket for a tank, I would suggest looking into ControTrace.  It is an external heating jacket that has a lot of engineering behind it.

The thread referenced by EGT01 will give you all you need to know about the heat transfer coefficients, but I would like to comment on a practical point.

A very important difference between the different types of jacketing methods (but which was not listed by perdog) is that they have very different abilities to withstand pressure external to the shell. A half pipe jacket will take a relatively high pressure, whereas an anular jacket will require a very thick shell to withstand the external pressure because of the larger unsupported areas.

I recently saw a tank destroyed because the operator left the jacket's cooling water return valve closed and just the pressure of the cooling water buckled the shell beyond repair. You can also have problems if the jacket is isolated and then a hot liquid is added to the tank. This can cause expansion or phase change in the jacket, leading to massive pressures. Always install relief valves if this is a risk.

I have used half pipe (and even angle irons) as external coils quite successfully, but with low heat transfer coefficients and high pressure drops.  But they can be broken down into several parallel circuits.

I have also used dimpled jackets on low pressure refigerated water duties where we were simply maintaining the temperature (no actual cooling). The dimples aid turbulence, and the welds in each dimple give extra stability to the shell for the external pressure.

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