|
|
Jerry,
Despite the seeming evidence of cold side problems - its all relative. On
one version of my intake I had all four injectors 24" away from the intake
port. I had no problem flying with it or producing power with my NA turbo
block. In fact, it seemed based on a smidgen of data that I might be
getting 1/2 gallon/hr better economy (not conclusively proven), however, the
downside I found were three fold:
1. The throttle response was not to my taste - it would bog, if the
throttle was opened too suddenly. Some may feel that you shouldn't need to
ask for that kind of response from an aircraft engine - but, Scotty, when I
want more power - I WANT MORE POWER NOW!
2. Starting on cold mornings were horrid, ran the battery down a couple of
times. Now, my "Plugs Up" installation might have contributed to that
problem as the normal orientation any liquid fuel will run down into the
chamber where it might stand a chance of turning into vapor (or flooding the
engine), whereas my fuel would have to be lifted vertically.
3. It did appear that I could not lean out the engine quite as much without
it starting to stumble, it seem to take approx 1/2 GPH fuel flow to keep
that from happening - might have been evidence of some distillation - but,
who knows, could have been something else like fuel wetting out on the
walls. I know this seems in conflict with point #2, but that's what
occurred.
So I went back to all four injectors less than 3" from the ports. However,
there was no reason why I could not have continued to fly with that set up -
except for personal perferences. That rotary will do well even on less than
optimum configuration.
Ed A
----- Original Message -----
From: "Jerry Hey" <j-winddesigns@thegrid.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Friday, January 21, 2005 11:32 AM
Subject: [FlyRotary] Re: Pport/cold side injectors
Ernest, that your analysis is impressive. I've just reread it again.
I'm committed to trying with the cold side injectors but if it does
not work, I will understand why. The upside is that if they don't
work we can lay the idea to rest, accept hot side fuel as the only
way and work on making it safe through proper shielding. This is one
of the "little" things us p porters have to work out. Thanks, Jerry
On Friday, January 21, 2005, at 11:04 AM, Ernest Christley wrote:
> On Fri, 2005-01-21 at 10:23, Ed Anderson wrote:
>> Wow! Ok, Ernest
>>
>> Certainly sounds plausible that long runners would contribute to the
>> separation of the wheat and chaff. I wish I could remember what my
>> professors taught me in those long ago days. Perhaps if I had day
>> dreamed
>> less and studied harder......Nah!!!
>>
>
> I took only one other thing away from that class.
>
> What has LEAD got to do with octane? It's a metal. It doesn't burn.
> Why would anyone put it in their gas?
>
> Well, it turns out, the light (less carbons per chain) molecules are
> easier to atomize (convert to a semi-gaseous state by spraying through
> a
> small orifice). If you want a nice compact carberator/intake system,
> you need lots of those short chains. The down side is, those short
> chains don't have a lot of energy and tend to want to burn on there on
> when exposed to the pressure inside a cylinder. What you want is
> something that will atomize like the short chain, but burn smoothly
> like
> the medium length ones.
>
> Enter LEAD, stage right.
>
> Lead has four bonding points. Mix some with your gas, and each lead
> atom will attach to one end of 4 different carbon chains. Remember,
> the
> chain only burns when the end is exposed to oxygen? Well, now one end
> is locked down. If the fuel started out as pure mixture of 4 carbon
> chains, and you mixed just the right amount of lead, you'll end up with
> a batch of molecules shaped like a plus sign (+). Each arm of the plus
> will be 4 chains long. The oxygen can only get at the ends, so this
> mixture will burn like 100 Octane (ie, 100% Octane).
>
> And my last point. Higher octane is not always better. High octane is
> good for turbo applications, because is has a slower burn rate. But
> you
> want the burn to occur so that the maximum pressure is in the chamber
> at
> the highest torque point of the cylinder/rotor rotation. Not before
> and
> not after. If you're running exceedingly high RPM in a non-turbo
> application, LOWER octane may actually produce more power. In this
> situation, the higher octane stuff may still be burning well into the
> exhaust cylce.
>
> Now, I'm done. My brain is empty.
>
>>> Homepage: http://www.flyrotary.com/
>>> Archive: http://lancaironline.net/lists/flyrotary/List.html
>
>> Homepage: http://www.flyrotary.com/
>> Archive: http://lancaironline.net/lists/flyrotary/List.html
|
|