Radiator heat load of a Nissan V6 engine of 220 hp
Radiator heat load of a Nissan V6 engine of 220 hp
(OP)
I am required to convert the engine from RAW water cooling to a CLOSED cycle system. 220 hp @ block temperature of 160F, engine pump discharge I.D. is 2.0". We would like to stick with a SS shell and tube, Please specify the outer O. D. and GPM with a open intake and discharge on the floor of a boat. Can it be done with a length of 8' or less. Lake water is a maximum of 85F. Since my field is electronics, I am asking for help. I can not even make a guess of the actual heat loads involved.





RE: Radiator heat load of a Nissan V6 engine of 220 hp
You will have to calculate the brake mean effective pressure and brake thermal efficiency (which you need the fuel higher heating value and engine specific fuel consumption). From the output energy (BHP) and efficiency you can get the input energy. The difference is what your cooling system has to reject (minus heat out the exhaust, direct radiation from the block and lube cooling). Exhaust heat from flow rate and temperature. The rest nil for conservative answer.
From the temperature difference of the coolant and lake water, the thermal conductivity of the stainless steel and flow rates (both coolant and lake) you can back out the surface area.
Running the coolant at a higher temperature will reduce the radiator size.
85 F Lake water? Are there hot springs nearby?
RE: Radiator heat load of a Nissan V6 engine of 220 hp
RE: Radiator heat load of a Nissan V6 engine of 220 hp
You can probably get a lot of the thermodynamics answered on the thermodynamics forum. I found these sites which have some info:
http://www.mame.mu.oz.au/ugrad/436351/HX_kcb1.pdf
http:
About a third of the combustion energy goes into the cooling system and if your engine is a recent design you may get about 30% efficiency at best. If you assume you have to remove 250hp of heat you should be ok.
It's years since I worked on this but I found putting slight wiggles or kinks into the inside tubes improves efficiency (by agitating the flow a bit.) You can also tack a few mixing plates into the tube. Flow of the two fluids should be in opposite directions and it might be easier to double the cold water flow than double the surface area.
You can pick up brazed plate heat exchangers for very little at scrap yards and new they are not too expensive.
cheers, derek
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RE: Radiator heat load of a Nissan V6 engine of 220 hp
Jeff
RE: Radiator heat load of a Nissan V6 engine of 220 hp
RE: Radiator heat load of a Nissan V6 engine of 220 hp
RE: Radiator heat load of a Nissan V6 engine of 220 hp
TTFN
RE: Radiator heat load of a Nissan V6 engine of 220 hp
Regards
pat pprimmer@acay.com.au
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RE: Radiator heat load of a Nissan V6 engine of 220 hp
If you ask Marvin Beasley, he might even share it with you: tell him I sent you (grin).