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WRT turbocharging a Renesis, has anyone considered turbo-normalizing (boosting to a MAP no greater than 30") as a method to avoid detonation and maintaining power at altitude?
-Cedric Gould
On 1/4/2013 8:59 AM, Bobby J. Hughes wrote:
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.
Steve Boese
RV6A, 1986 13B NA, RD1A, EC2
------------------------------------------------------------------------
*From:*Rotary motors in aircraft [flyrotary@lancaironline.net
<mailto:flyrotary@lancaironline.net>] on behalf of argoldman@aol.com
<mailto:argoldman@aol.com> [argoldman@aol.com
<mailto:argoldman@aol.com>]
*Sent:* Thursday, January 03, 2013 2:43 PM
*To:* Rotary motors in aircraft
*Subject:* [FlyRotary] Re: turbo manifold
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> <mailto:SBoese@uwyo.edu>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
<mailto:flyrotary@lancaironline.net>
Sent: Thu, Jan 3, 2013 2:55 pm
Subject: [FlyRotary] Re: turbo manifold
Bobby,
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 Driveprop
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.
Steve
------------------------------------------------------------------------
*From:*Rotary motors in aircraft [flyrotary@lancaironline.net
<mailto:flyrotary@lancaironline.net>] on behalf of Bobby J. Hughes
[bhughes@qnsi.net <mailto:bhughes@qnsi.net>]
*Sent:* Thursday, January 03, 2013 1:33 PM
*To:* Rotary motors in aircraft
*Subject:* [FlyRotary] Re: turbo manifold
Steve,
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.
Bobby
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