In Chamber Testing - Page 5

Libor · 06-04-2011, 08:50 PM

Bump this up.

Barry, are you going to do some tests with tighter or zero split?

Also I think there is slight misconception when should peak pressure occur. IIRC at 45° ATDC, rotor has most mechanical leverage over e-shaft, but peak pressure for optimal efficiency should occur much earlier.

Otherwise best of luck with your testing

Barry Bordes · 06-05-2011, 08:16 AM

Quote:

Originally Posted by Libor

Bump this up.

Barry, are you going to do some tests with tighter or zero split?

Also I think there is slight misconception when should peak pressure occur. IIRC at 45° ATDC, rotor has most mechanical leverage over e-shaft, but peak pressure for optimal efficiency should occur much earlier.

Otherwise best of luck with your testing

Libor and DOHC,
You know how the rotor moves at 3:1 ratio to that of the eccentric shaft. That seems to be the sweet spot for the rotary, that is, 15º times 3 or 45º. This latest run with the new sensor has gone to 1000 psi for the first time. But the highest pressures seem to be around 45º. I think I am seeing a slight deviation in this with rpm.

But I have exactly the same thoughts as you. Looking at the chart, if we could have the ignition pressure rise as a continuation of the initial compression curve it would seem to be logical.

Barry

Libor · 06-05-2011, 08:36 AM

Quote:

Originally Posted by Barry Bordes

But I have exactly the same thoughts as you. Looking at the chart, if we could have the ignition pressure rise as a continuation of the initial compression curve it would seem to be logical.

Barry

Exactly. I´ve been lately looking at these charts - granted, they come from piston engines but principal is the same. Pressure rise seems very delayed. And burn rate is so much different from piston engines, also takes much more time.

But as I said, carry on your testing! Nothing is better than actuall data

Barry Bordes · 06-05-2011, 01:15 PM

This chart actually predicts the sweet spot.

You have to look closly to see the location where pressure is highest. Too bad we don't have more hits around 40º.

Then you go to your ignition adjust the timing.

Barry

06-04-2011, 08:50 PM	#61
Libor Rotary Fan in Training Join Date: Aug 2010 Posts: 54 Rep Power: 15	Bump this up. Barry, are you going to do some tests with tighter or zero split? Also I think there is slight misconception when should peak pressure occur. IIRC at 45° ATDC, rotor has most mechanical leverage over e-shaft, but peak pressure for optimal efficiency should occur much earlier. Otherwise best of luck with your testing

06-05-2011, 01:15 PM	#64
Barry Bordes Rotary Fanatic Join Date: Feb 2008 Location: Slidell, LA Posts: 191 Rep Power: 18	This chart actually predicts the sweet spot. You have to look closly to see the location where pressure is highest. Too bad we don't have more hits around 40º. Then you go to your ignition adjust the timing. Barry