Dear all,
I have doubt while entering the Design Temperature for Heat exchanger in the tubesheet analysis data.
can anyone please tell me what will be the design temperature for the tubes if channel side design temperature is 65 degree celsius & shell side design temperature is 200 degree celsius ?

Dear all,
I have doubt while entering the Design Temperature for Heat exchanger in the "Heat Exchnager tubesheet input".
can anyone please tell me what value could i enter in the tube temperature box if channel side design temperature is 65 degree celsius & shell side design temperature is 200 degree celsius ?

I am assuming that your question is about the tube design temperature and not the mean metal temperature along the tube.

The tube is contact with both the shell side fluid and the tube side fluid. If you want to design for the case where there is a loss of fluid on either shell or channel side, then use the higher of the 2 design temperatures.

I do not think anybody can question if you specify the tube design temperature as higher of the shell or tube design temperatures.


Maybe somebody more experienced with heat exchanger design can comment.

The correct and most perfact way for tube design is to enter internal pressure of tube with its internal temperature i.e. channel side parameters and external pressure with its external temperature i.e shell side parameters...

For tubesheet design, generally enter higher of the temperature from shell or tube side for conservative design.

Mukesh
www.theculminates.com

Hello Marks

I think you are referring the mean metal temperature of the tubes. As you correctly point out, the tubes are subject to both the tubeside temperature and the shell side temperature. To further complicate matters, the fluid (shellside and tubeside) enter at one temperature, and exit at another temperatures. There are therefore 4 terminal temperatures involved.

I the case of the mean metal temperature of the tubes, one method is this; take the average of the 4 terminal temperatures. You can do this in the absence of more detailed information

Hello Marks,

For Heat exchangers, parts which are in contact with both shellside and tubeside i.e. tubes/tubesheet, design temperature shall be higher of the two.

Most of the client/PMC specification specifies this requiremt.