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Well, Mark - perhaps in the future
Only so much time and so many things that would be fun to
try. IF I interpret the charts correctly the P + S type intake
configuration appears to provide much more intake port area than either the P or
S type along. Makes sense - if you have twice as many intakes it has more
area. Supposedly the P+S overcomes the low rpm idle problem of the PP
alone.
But, for aircraft usage, I think Richard is on the money,
you don't really spend much time at idle in aircraft usage and I idle
above 1600 rpm in any case, so who cares {:>) - just go with the P
port.
However, I am intrigued by the large intake area that the
P + S configuration has over even the PP alone and what that might potent
for POWER! More Power, Scotty!!!!!
Saw some information on the Renesis in an SAE paper that
indicates the six port (They call it the HIGH POWER Renesis) produces 40% more
power than the standard 13B. They did not make a comparison to the 4 port
Renesis but presumably it produces less than the six port Renesis but more than
the older 13B. They also didn't specify the rpm point that occurred, but I
assume it must be near its maximum. Also, its not clear if this figure was
based on the earlier 250 HP claim for the Renesis by Mazda or the later adjusted
237 HP claim (actually I'd take either one) .
The intake configuration and operation on the six port is
quite involved, but they do make use of the Dynamic Effect. They call it
the Sequential Dynamic Air Intake System (S-DAIS). Since there is no
intake/exhaust port overlap in the Renesis, they appear to make use of the "A"
pulse which is the pressure wave created when the high velocity air in the
intake slams into the closing port and bounced back down the
manifold. They then have several valves that activate at different
rpm/air flow situations that control the sequential activation of elements of
the S-DAIS.
As well as the "A" pulse, the older NA 13B DEI also
used the stronger "B" pulse created when the intake opened releasing a burst of
the trapped exhaust gas residue to create a power shock wave which raised the
manifold pressure at the second rotor's intake. But, since there is no
intake/exhaust overlap with the Renesis side ports, it would appear that
only the "A" pulse is used to enhance power.
Ed
----- Original Message -----
Sent: Monday, June 18, 2007 9:12 AM
Subject: [FlyRotary] Re: Fw: Different
Rotary Port configurations
Thanks Richard for the clarification.
Mark S.
(Looks like I should have typed a little faster.)
On 6/18/07, Mark
Steitle <msteitle@gmail.com>
wrote:
Well Ed,
It looks like you've got yourself a new intake project. Didn't
Richard Sohn try running side and peripheral intake porting on his one
rotor? I vaguely remember him mentioning it and that he abandoned
the idea. I think it had something to do with the complexity of
the dual runners and that he was satisfied with the idle characteristics of
the p-port? Maybe Richard can comment?
Mark S.
On 6/17/07, Ed
Anderson <eanderson@carolina.rr.com > wrote:
Ok, here's the answer to my question. The
second image shows a three barrel carb with the primary going to two side
intake ports and the secondary going to the Peripheral ports.
Interesting concept.
Ed
----- Original Message -----
Sent: Sunday, June 17, 2007 10:15 PM
Subject: Different Rotary Port configurations
Ok, getting a bit quite again. Here is
something that some of you may find interesting. Its a graph
comparing the possible different port configurations for the Rotary
engine.
The top graph shows the intake and exhaust port
opening for a engine with a peripheral intake and peripheral exhaust -
such as a 13B which has been converted to a PP intake.
The trapezoidal shapes show the port area. For
example on the first graph the first rectangular area entitled PORT shows
the Peripheral exhaust port open at 63Deg ATDC. There are two
trapezoid areas shown for the Peripheral intake. A "P" which I
presume stands for Primary and a much larger P+S which I presumes stands
for a combined primary and Secondary port. Although, I do not ever
recall a PP with two tubes one for primary and one for secondary. So
there may be another explanation.
The second graph is our traditional 13B with
sideport intake and peripheral port exhaust. Here the intake timing
for the intake is that of the NA 13B although it shows the intake
opening a bit later than the stock 13B but closing at the stock 40 deg
ABDC.
If you look at the area under the first graphs "P"
trapezoid it appears to be open much longer than the P for the side port
intake (2nd graph), but the trapezoid is not as high. Wonder what
that signifies? Open longer but not as large a port area?
Anyhow, thought some of you might find it
interesting.
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