Mailing List flyrotary@lancaironline.net Message #55603
From: Andrew Martin <andrew@martinag.com.au>
Subject: Re: [FlyRotary] generator and dyno prop
Date: Tue, 5 Jul 2011 12:16:12 +0800
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
how many amps is the Harley generator capable of?

I reckon the calculation for the dyno-prop goes out the window if the 15 to 1 ratio is not adhered to.

Andrew

On Tue, Jul 5, 2011 at 11:51 AM, Ernest Christley <echristley@nc.rr.com> wrote:
I tested the dyno-prop today.  I had been waiting to complete some rework on the Harly-Davidson generator I'm using.  I was trying to pass control back to the pilot by putting a solid-state relay inline with the regulator's output.  The relay appears to have either interfered with the proper operation of the regulator, or caused enough of a voltage drop to make the generator unable to charge the battery.  Either way, the relay is out, and a 80A fusible link is in.  I'm now getting 13.5V at 4000rpm.

Which leads me back to the dyno-prop.  I got lazy and didn't cut down the 88mm wide prop I built.  I didn't want to take the time to balance it again.  At 40% throttle, I had the engine up to 4000rpm (1258 at the prop).  That would be 26Hp if the prop was of the correct length.  I know I was generating more than that, but I haven't a clue how much more.

OAT was somewhere between 97* and hotter-n-hell.  The logs show the MAT was 103* (measured at the throttle body).  The graph of the coolant temp climbs at a 30 degree angle.  In 50 seconds, I went from 162* to 192*.  That's with a blower stuck into the intake for the single radiator.  Luckily, I think I've reached the point where I can put the cowl on, and start using the second radiator.

--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.html



Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster