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Message-ID: <000601c513bd$b1cf0b90$2402a8c0@edward2>
From: "Ed Anderson" <eanderson@carolina.rr.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
References: <list-740582@logan.com>
Subject: Atmospheric Pressure Reg wasRe: [FlyRotary] Re: Fuel System Design - Jet Pump
Date: Tue, 15 Feb 2005 19:23:07 -0500
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 I don't think so, Ernest.  Remember the pressure regulator is attempting to
keep the pressure differential between manifold pressure and fuel rail
pressure constant across the injectors - so that the same amount of fuel
will be injected for each ms of injector open time.  The only thing the
atmosphere does is set the upper limit of manifold pressure that the sensor
will see.  You can still get 12 " HG at altitude with the throttle closed,
you just can't get 29.92 (unless with boost of course).

Ed A


> On another topic, looking at the pages on fuel pressure regulators.
> They mention 3 types.  The one we've been discussing, wherein the fuel
> rail pressure referenced to the manifold, a constant pressure type, that
> is just reference to a spring, and the one I found intriguing, the
> atmospheric referenced type.
>
> It seems like the atmospheric type would work best for an airplane.
>
> >>  Homepage:  http://www.flyrotary.com/
> >>  Archive:   http://lancaironline.net/lists/flyrotary/List.html
>