|
|
| Ya don't want to pay the fuel or maintenance on anything burning kerosene..I take your point on less airflow. Can you tell me which pressure is greater in the intake manifold, the influence of ram air pressure or intake vacuum pressure. Or does it vary from one to the other according to the cycle.
For an "automatic" homegrown system on a 2 rotor would it work to have a spring loaded door opening inward into the intake manifold, fed by interior cowling air when the main system is blocked. It makes sense to me to have a door open for a negative pressure in the intake manifold which i imagine would be the case of a blocked regular air intake and ongoing intake vacuum pressure. Would a door like this be kept shut under normal conditions of positive ram air, to preserve ram air which is what we want?
Alex M On Sun, Jul 7, 2013 at 12:08 AM, <ARGOLDMAN@aol.com> wrote:
Interesting concept, I can see how that would eliminate a lot of FOD,
however that is not how alternate air systems work for piston/rotor type
engines.
That is almost the reverse. My guess is that the airflow in the PT6 is
hughly greater than in a 2 or 3 rotor engine and the kinetic energy of the FOD
is significantly less. Additionally, the alternate air is to allow air to flow
if the induction system gets blocked. this valve works in the reverse. The
greater the pressure upstream the more it will open and in fact will vent the
presure (FOD/rain etc) overboard
If the intake becomes blocked as in a filter or induction icing, the
pressure is reduced tending to seal the manifold.at this valve.
Would that we could all fly Turboprops
Rich
Hello
Lynn
Are you referring to a similar system you see on the Pratt and Whitney
PT6 series engine, basically reversing the flow of air 180 degrees before
entering the compressor (throttle body for us i guess). The inertia of the FOD
or ice particles doesn't let them "make the turn" into the throttle body and
they exit the duct via a bypass flap. In this case the opening of the flap
creates the 180 degree turn and spillover air exit?
Alex M
|
|