Bobby,
Thanks for this info. I had
originally decided that I would stay away from a turbo on the Renesis, but I have
come to realize that I will not be happy with the current power output. My
plane is heavier than the RVs that most are using and as a result, I just need
a little more punch. Actually, I would rather go with a 20b, but the expense
and the size of the job kind of get in the way. I think I could add a
turbo a little easier and cheaper than changing to a 20B. But, having
never considered a turbo, I am starting from scratch on what and how to do it.
So, oil feed, I suppose I could either put
in a “T” fitting at the oil pressure sender, or I could use the
original oil pressure tap under the filter stand with an elbow to feed the
turbo.
Then, oil drain, I don’t see how a
turbo could be mounted high enough on the rotary to provide a gravity drain
into the oil pan. I have installed the older 13B pan under the mount
plate, and my engine holds about 8 qts of oil up to just below the bottom of
the mount plate. Even if I somehow modified the oil pan and lowered the
oil level, it seems that it would still not gravity feed from the turbo because
of how low it seems that the turbo would have to be mounted. I would
really like to see some pictures of how the turbo was mounted.
Then, water cooling of the turbo, I have
a heater hose set up that I am not currently using that I suppose I could run
thru the turbo to cool it. I have read that it may not be necessary to do
this. What are people doing about the water cooling? Use it or not?
Then some questions about your
chart. I have not seen 7125 rpm on my engine, but I am pretty certain
that I am not getting 175 HP at 5700 rpm. In fact, I doubt that I am
getting much more than that at 6500 rpm. Where did you get your numbers
and do you think that these hp numbers are what you are really getting while NA
and while boosted? It may just be that my plane is about 500 lbs heavier
than the RVs, but back when I was trying to turn the same prop that Ed has, I could
only get about 5300 static where he was getting 6000 with that prop.
I don’t understand how you are
cooling the intake charge if you don’t have an intercooler?? What are
you putting the water injection on? Radiator?? You are not spraying
it into the intake???
Please direct me to some info on the “surge
line”. I have heard of it, but don’t understand it or really
know what it is.
If I could get the HP numbers that you
show below a sea level under boost, I would be a happy camper!!
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bobby J. Hughes
Sent: Friday, January 04, 2013
12:00 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: turbo
manifold
Bill,
The rear iron
housing feed is not drilled but can be. Mine was tapped and plugged during
assembly. You could also feed from the oil galley at or below the filter pad.
Might be able to use the stock oil pressure sender port. Not sure about the
return with a stock oil pan. I have a deep pan and can keep 4.5 quarts below
the oil return fitting in both climb and decent attitudes. I added and plugged
an oil return last year in case I decide to swap out the super charger for a
turbo. I think you can safely boost the renesis 10:1 rotors with 3-4 pounds as
long as your intake charge is cooled and you don’t have a lean fuel
condition. I run 38-40” MP for takeoff and initial climb. No intercooler
but I do use water injection for a safety margin.
The table below may contain
errors and is a work in progress. I believe an effective turbo system would
need to be capable of producing 6-7 pounds to provide enough exhaust flow at
altitudes up to 18K. The turbo surge line becomes a problem with cruise rpm and
higher pressure ratios. An intercooler appears to be necessary. I used a Texas summer OAT of 100F
as a starting point for calculating the intake temperature.
Bobby
Prop
RPM
|
Engine
RPM
|
Renesis
HP @ standard day
|
4
psi Boost HP
|
HP
@ 0'
|
HP
@ 8,000'
|
HP
@ 10,000'
|
HP
@ 18,000'
|
|
|
|
|
|
|
|
|
|
|
1700
|
4845
|
140
|
38.0
|
178
|
135
|
125
|
82
|
Estimate 10 HP per
pound of air.
|
2000
|
5700
|
175
|
47.6
|
223
|
169
|
156
|
103
|
|
2500
|
7125
|
215
|
58.5
|
274
|
208
|
192
|
126
|
|
Pressure Ratio
|
|
|
|
1.36
|
1.5
|
1.55
|
1.79
|
Assumes 1psi
pressure drop on intake prior to turbo for filter
|
Compressor Eff
|
|
|
|
0.65
|
0.65
|
0.65
|
0.65
|
|
Standard Lapse Est
OAT
|
|
|
|
100
|
72
|
65
|
37
|
|
Intake
Temp @ 65%
|
|
|
|
173.3
|
164.7
|
163.5
|
163.1
|
Tout = Tamb +
(Tamb * (-1 + PR0.263)) / comp efficiency
|
Temp Increase
|
|
|
|
73.3
|
92.7
|
98.5
|
126.1
|
|
|
|
|
|
|
|
|
|
|
Temperature
Adjusted Net HP
|
|
|
|
|
|
|
|
|
1700
|
4845
|
140
|
38
|
160.67
|
118.53
|
108.25
|
65.49
|
1%per 10F = hp
loss with air temperature rise
|
2000
|
5700
|
175
|
47.6
|
205.27
|
153.01
|
139.65
|
86.29
|
|
2500
|
7125
|
215
|
58.5
|
256.17
|
191.53
|
175.65
|
109.69
|
|
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bill Bradburry
Sent: Friday, January 04, 2013
9:44 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: turbo
manifold
Am I wrong? I don’t think that
there is a stock turbo oil source and return on the Renesis? It is not
factory turboed.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]
On Behalf Of Dave
Sent: Friday, January 04, 2013
9:53 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: turbo
manifold
Stock turbo oil source on top of front iron, stock
turbo oil return on the front cover/iron.
Dont boost 10:1. Get low compression rotors. Even with intercooling, your turbo
will increase your intake air temp very significantly, and eat into detonation
margins. It only takes a few seconds to destroy your apex seals.. quicker than
you can detect and react.
On 1/3/2013 11:22 PM, Bill Bradburry wrote:
How are the folks with turbos handling the
plumbing? Where are you picking up the pressurized oil and where/how do
you return the oil to the crankcase? I read in the install instructions
that the oil drain line should be one inch in diameter, return above oil level
in the crankcase, and have no traps in it. That doesn’t seem
possible with the rotary?? How are you doing it?
How far would it be safe to boost the
Renesis with the compression at 10:1?
Where are you picking up the water for the
water cooling of the turbo?
Does anyone have any good pictures of the
installation that shows these things?
B2
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
On Behalf Of Steven W. Boese
Sent: Thursday, January 03, 2013
5:53 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: turbo
manifold
Rich,
A load cell was installed on one side of the engine mount
to measure torque. HP was calculated from the torque and the RPM.
Most installations with a Renesis engine appear to be using a higher gear ratio
than the 2.18:1 ratio of the reduction drives that I have. This lowers
the limit the of engine RPM that I am able to achieve with a prop suitable
for flight.
The HP required to turn the prop at a given static RPM does
not change if the atmospheric conditions haven't changed. At the highest
MAP of 21.5" shown on the chart for the NA 13B, the 13B HP is very close
to the HP of the Renesis at that same MAP. The test data on the chart was
generated as a first pass at assessing the suitability of turbocharging
the Renesis compared to the 13B engine. None of the
configurations should be considered to be optimized.
RV6A, 1986 13B NA, RD1A, EC2
I had assumed that these were dynamometer results. By
what method did you ascertain the HP listed?
Interesting results. If the blades stalled (overpowered) at such a low RPM
would it be correct to assume that at that RPM the engine was producing more
power than the non Renesis engines at the same RPM with the same prop???
I am so confused... interested also in perhaps turboing the renesis in the
future??
Please help
Rich
-----Original
Message-----
From: Steven W. Boese <SBoese@uwyo.edu>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, Jan 3, 2013 2:55 pm
Subject: [FlyRotary] Re: turbo manifold
I honestly don't know what the exhaust sound was
like. The control panel for the test stand is on the opposite side from
the exhaust outlet. Also, at RPM above 5200, the 3 blade Warp Drive prop
was stalled and the prop noise was just deafening. I could
feel what seemed to be ground vibrations in my feet so testing higher
power levels was disconcerting. At RPM below 5200, the noise was similar
to having the GM diesel truck muffler on the NA 13B.
From: Rotary motors in aircraft [flyrotary@lancaironline.net]
on behalf of Bobby J. Hughes [bhughes@qnsi.net]
Sent: Thursday, January 03, 2013
1:33 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: turbo
manifold
How did it sound
without a muffler? I removed my belly muffler for a speed run and it was not
tolerable in the cockpit. Only picked up 1-2 mph so the muffler is back on.