Subject: [FlyRotary] Oil Coolers

 

I have found some really nice oil coolers for aircraft (and other) at http://lytron.com/standard/he_aluminum.asp They are a little expensive but are suppose to have great performance.

Does anyone know how much what the average oil flow rate of the 13b is (Gal/hour) and the required heat dissipation (W) or (BTU/hour)

 

Alex Madsen

 

Alex;

 

Heat dissipation to the oil is between 10 and 11 Btu/min per hp.  My opinion is to design for about 75-80% power, so for a NA 13B figure about 1450 Btu/min.

 

I’ve seen different oil flow rate curves that don’t quite agree; but best figure about 12 gpm at 5000 rpm, and fairly linear with RPM up to that point, maybe hits 15-16 gpm at 6500.  I’ve seen one dyno curve that maxed out at about 11 gpm; who knows –different pump, different back pressure.

 

One issue for us with rotarys is the flow rate 30% or so higher than the typical piston engine; so its worth checking the flow – pressure drop data for “stock” coolers designed for piston engine use.

 

Al