Does anybody know of a system of jacket water cooling system using a buffer tank in between the engine and cooling tower? What could be the justification for this buffer tank?
If you were in a very environmentally sensitive area you might want to make sure that the cooling tower water was uncontaminated. Or you might want to use evaporative cooling. Or... well there's a lot of possibilities, none that are common.
Water to fluid, or fluid to water, heat exchangers are very common in automotive systems. In fact I think the Prius actually runs a water to water heat exchanger.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
In our case, we desire to provide high positive suction head for the coolant circulating pumps, as they are pumping hot (160 F) water. Additionally, typically we have multiple engines sharing a common cooling system, cooling tower, pumps, etc.
The term 'jacket water', in Diesels at least, usually refers to a glycol/water loop that's usually closed, pressurized and thermostatically regulated to 160F or thereabouts.
That loop is typically cooled by:
radiators, or
heat exchangers and seawater, or
heat exchangers and a cooling tower loop with freshwater makeup
Engine manufacturers often >>strongly suggest<< the use of sizable air separators in the liquid circuits, just to make sure that the pumps are pumping liquid, etc.