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Old 06-06-2003
geohan geohan is offline
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MD3B Volvo-Penta sea water to fresh water conversion

Peter I don''t recall the size of your engine so I''ll give you a per horsepower figure for cooling water requirements. The basic assumption was that about 1/3 of the fuel energy goes to mechanical output, 1/3 to exhaust gasses, and 1/3 to the cooling water. Ref: Marine Engines and Equipment, Robert Latham, Associate Professor, Engineering Dept., U.S. Naval Academy. This was (is?) a text used in USPS courses. All of this boils down to my design criteria of 5-Horsepower per gallon per minute of cooling water raised 25-degrees F. I believe this to be conservative. My exhaust felt warm but not hot and I can only guess at about 2 gpm flow rate for the 12-HP gasoline engine. A diesel engine cooling water requirement might be a bit higher but I''d guess only l5% or less. I used a 3/8" neopreme vane pump at about 1700 RPM but don''t know how much of the flow was being recirculated through the thermostat to maintain the 180-degree temperature. Regards, George
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