Subject:
[FlyRotary] Re: Cooling oil
-----
Original Message -----
From:
"Joseph Berki" <joseph.berki@grc.nasa.gov>
To:
"Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent:
Thursday, June 10, 2004 12:39 PM
Subject:
[FlyRotary] Re: Cooling oil
>
It would be interesting to measure flow in both engines. I thought that
>
both Lycoming and Mazda engines rejected 2/3 heat load through the
>
oil that is why I started going down this road. If the engines
generated
>
the same Hp than the heat load should be similar.
>
>
Joe Berki
Joe,
both engines may generate the same heat load, but the proportion
rejected
through the coolant in case of the Mazda is 2/3 of its waste heat
while
the oil rejects another 1/3 of the waste heat. Neither engine rejects
anywhere
near 2/3 of its waste heat through the oil.
Most
aircraft engines reject on the order of 300-600 BTU/Min through the
oil,
the Mazda at 160HP rejects approx 2446 BTU/Min through the oil.
Ed
Anderson
Ed;
That number looked a
bit high to me, so I went in to my file to check. My data shows 28% of
the fuel burn energy in the rotary gets converted to HP, 18% goes to the
coolant, and about 7% to the oil. Most of the rest goes out the exhaust pipe.
For 160 HP output, I think that should be 1725 BTU/Min going to the oil cooler.
So about 3 times the comparable powered Lyc.
Double check me on
this.
Al