3 replies to this topic

[Bill B7]

We are currently pumping cooling water to a portion of our facility using underground piping, and are looking at running it overhead about 25', then dropping it down to coolers, then back up to 25', then finally back to ground level.    Once done, the origination and termination points will be in the same location (call it elevation = 0).

 

Theoretically, the elevation change (net = 0) should have no impact?

 

The pump can over come the 25' elevation should the line be void when starting up, but I would like to be sure I am not missing something.

 

Thanks

[latexman]

It's not clear if this applies to you, but cooling water RETURN headers after they pick up heat may cavitate at higher elevations.  Is that an issue for you?

[Pilesar]

You might be missing something. I would suggest a hydraulic study. Are you sure the water lines will all be liquid-full? What will happen to the air in the down-legs to the exchangers on startup? If air remains in the down-leg, does that mean that the system will be at atmospheric pressure at the top of the down-leg? If so, then what would drive the water through the exchanger and back up to the same elevation? Are there parallel paths to other parts of the facility from the same pump? What calcs could you do to really know what the pressure profile of the system will be? I've modeled hydraulics of large cooling water systems and it can be a major effort. Maybe you could make assumptions and use short cuts, but if there is no engineering done then what would be the excuse?

[breizh]

Hi,

A sketch will help !

my 2 cents

Breizh