X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-ma06.mx.aol.com ([64.12.78.142] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4124495 for flyrotary@lancaironline.net; Sat, 13 Feb 2010 23:55:34 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.78.142; envelope-from=SHIPCHIEF@aol.com Received: from imo-da04.mx.aol.com (imo-da04.mx.aol.com [205.188.169.202]) by imr-ma06.mx.aol.com (8.14.1/8.14.1) with ESMTP id o1E4sjqq012768 for ; Sat, 13 Feb 2010 23:54:45 -0500 Received: from SHIPCHIEF@aol.com by imo-da04.mx.aol.com (mail_out_v42.9.) id q.ca6.5c80b6a7 (37555) for ; Sat, 13 Feb 2010 23:54:39 -0500 (EST) Received: from smtprly-mc03.mx.aol.com (smtprly-mc03.mx.aol.com [64.12.95.99]) by cia-mb03.mx.aol.com (v127.7) with ESMTP id MAILCIAMB034-d3d74b778209129; Sat, 13 Feb 2010 23:54:39 -0500 Received: from webmail-d096 (webmail-d096.sim.aol.com [205.188.255.7]) by smtprly-mc03.mx.aol.com (v127.7) with ESMTP id MAILSMTPRLYMC031-d3d74b778209129; Sat, 13 Feb 2010 23:54:33 -0500 References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Throttle limits was Re: N.A. Renesis to turbo Date: Sat, 13 Feb 2010 23:54:33 -0500 X-AOL-IP: 24.19.204.151 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: shipchief@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CC7B48EF200831_8A50_1DCEB_webmail-d096.sysops.aol.com" X-Mailer: AOL Webmail 30746-STANDARD Received: from 24.19.204.151 by webmail-d096.sysops.aol.com (205.188.255.7) with HTTP (WebMailUI); Sat, 13 Feb 2010 23:54:33 -0500 Message-Id: <8CC7B48EF14214C-8A50-F008@webmail-d096.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: SHIPCHIEF@aol.com ----------MB_8CC7B48EF200831_8A50_1DCEB_webmail-d096.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" George; You were discussing (earlier) the effect oil temp has on volumetric effici= ency, namely that oil temps of 160 are cool enough to alow a good air char= ge to enter the chamber, but higher oil temps caused rapid adiabatic expan= sion of the air, reducing air density, reducing power. Is that an acceptab= le summary? Anyway, I was looking at the direct injected 16b engine depicted on PL's= site, and had to wonder?? would this fuel spray cool the intake air charg= e via direct contact cooling fast enough to increase charge density and va= porize the fuel better too? (win-win)? Especially in a P Port engine?=20 Just wondering Scott -----Original Message----- From: George Lendich To: Rotary motors in aircraft Sent: Sat, Feb 13, 2010 1:20 pm Subject: [FlyRotary] Re: Throttle limits was Re: N.A. Renesis to turbo Bill, I have stated this before and I will gain, my calculations indicate a 44mm= inlet ( per rotor) being the size needed to 7,500 rpm - giving max inlet= velocity ( of 100/120 mph). It wasn't until I seen that the Powersport PP= inlet tubes were 44mm that I was reassured I was on the right track. Othe= rs that we know push for the 3" ( 75mm) TB, such as the Renesis TB, nice= that it is. =20 Not many builders will go to 7,500 rpm so 44mm is slightly overkill. Probably could go as low as 38 to 40mm for lower RPM, but I would have to= crunch the numbers. At the time I was thinking I would have to go to 7,50= 0 RPM on the single rotor to get max take-off performance, so worked with= those numbers. Of course the lower the inlet diameter the higher the velo= city and the better the VE. =20 Lynn spoke of 38mm and 44mm chokes, If I remember correctly and chokes the= y are in his racing application of much higher rpm, but the trade-off is= inlet velocity. =20 I know one of the ex-Powersport people are making ( machining) 44mm PP wit= h 2 piece inlet tubes and fitting them to housings with O rings. I believe= this service is available to anyone interested. Information passed to me= was that Powersport never had any sealing problems after they went to thi= s arrangement. Believe you me, they spent a fortune on development. =20 I'm just wondering how I'm going to get my housing over there to get it do= ne. George ( down under)=20 Ed, This throttle body size thing came as a surprise to me a couple of years= ago when I first started my engine. I selected the 75MM size because tha= t was what was in the RX-8 car. It pretty obviously is way too large for= our application. Apparently even the 65 MM that Dennis is using appears= to be too large. I suppose that is because in the car, the engine can re= v to 8K+ rpms. We are only revving in the 5-6K range with an occasional= outlier up in the low 7K range. The fact that the car can rev so high,= I suppose, is the reason that there are no complaints about dead pedal in= the car. Thanks to you, I feel I now understand what is causing the phenomenon. I= don=E2=80=99t see that it is a problem that should be fixed, at least, no= t yet. I just need to work on getting the engine to produce the most powe= r it can and then, maybe, resize my prop to get rpms in a good power band= for takeoff. =20 It seems that I remember someone on the list (probably Lynn) talking about= a couple of carb throats being 44MM that he uses. If so, they (two of th= em) would have an area of about 3040 MM. A single 65 MM body would have= an area of 3317 MM.. an increase of over 9%. A 75 MM body would have an= area of 4415 MM=E2=80=A6a whopping 45% increase! =20 Bill B =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Be= half Of Ed Anderson Sent: Friday, February 12, 2010 4:38 PM To: Rotary motors in aircraft Subject: [FlyRotary] Throttle limits was Re: N.A. Renesis to turbo Bill, if Dennis had a TB just big enough that it exactly provided 100% po= wer at sea level, then as he increases in altitude, he will find more and= more throttle travel that does nothing to increase power. This is becaus= e it takes less and less throttle plate opening to provide sufficient airf= low for the pressure/air density in the manifold to reach the ambient pres= sure/air density (ambient density is decreasing with altitude). Since tha= t air density is less than at sea level, it requires less throttle opening= to reach than at sea level. =20 The position of the throttle plate affects only the air flow volume (not= the density of that air airflow), but the amount of air flow volume does= determine the air density in the manifold. The external atmospheric pres= sure is of course what is forcing the air through the throttle body =E2=80= =93 The less air pressure at altitude means less air is flowing through th= e TB as you gain altitude. Remember even though to simply the verbiage -= we often talk of the engine =E2=80=9Csucking=E2=80=9D but of course it do= es not. The engine simply opens its ports and whatever pressure is in the= manifold forces that air into the essentially empty combustion chamber.= =20 =20 Think of it this way, there are two ways you can have ambient air density= in your intake manifold. Those two ways are with the throttle open or the= throttle closed =E2=80=93 a contradiction? Not, so. You may have ambien= t air pressure/density in the manifold when the engine is running and TB= open sufficiently to provide ambient pressure in the manifold OR when the= engine is not running. =20 When the engine is stopped - you also have ambient pressure in your intake= even with your throttle 99.99 % closed because the engine is not =E2=80= =9Csucking=E2=80=9D any air out of the manifold when stopped. So a small= leak in the throttle bottle is sufficient for the manifold pressure to re= ach and maintain ambient when the engine is not running.=20 =20 What Dennis has done with his DIE intake does not change this factor, but= what the pulse in the intake does when it reaches the other end of the in= take manifold (note how his intakes are tied together so the pulse can tra= vel from one intake port of one rotor to the intake port of the second rot= or) is briefly create a localized pressure increase in the intake manifold= right at the intake port as it is open. This in effect shoves more mixtu= re into the combustion chamber =E2=80=93 in effect it is a very brief supe= rcharger effect. It only lasts for milliseconds and therefore you don=E2= =80=99t get the same power increase that you would if you had a turbocharg= er pushing in denser air the entire time the intake is open. On the othe= r hand you don=E2=80=99t have 30-50 lbs more weight and for basically no= more than fabricating your intake different =E2=80=93 it=E2=80=99s basica= lly a free lunch.=20 =20 But, as Dennis will tell you - doing the analysis to get the equations so= you get dimension correct for the effect =E2=80=93 can give you a headach= e {:>) =E2=80=93 right Dennis??. =20 So, anyhow, back the throttle travel, if your TB is larger than needed to= reach 100% power at sea level, then you would also find =E2=80=9Cexcess= =E2=80=9D throttle travel sitting on the ground with the engine running at= WOT. Once the throttle is opened sufficient for manifold pressure to rea= ch ambient, then opening it further will provide no increase in power. Yo= u have in the vernacular- =E2=80=9CMaxed Out!=E2=80=9D {:>) =20 Once the throttle plate is open sufficient to permit the manifold pressure= /air density to reach ambient conditions =E2=80=93 no further opening will= produce any more power even though you may have 5=E2=80=9D of throttle tr= avel and 50% more throttle plate opening to go. =20 =20 =20 Ed =20 =20 =20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Be= half Of Bill Bradburry Sent: Friday, February 12, 2010 3:33 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: rpm vs Power was : Throttle limits was Re: N.A.= Renesis to turbo =20 Thanks, Dennis, It sounds like you still have a little unused throttle travel even with th= e new intake. Can you provide design measurements for your new intake? I ask only if yo= u have no plans to make and sell it. =20 Bill B=20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Be= half Of Dennis Haverlah Sent: Friday, February 12, 2010 2:20 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: rpm vs Power was : Throttle limits was Re: N.A.= Renesis to turbo I used the same 65 mm Mustang throttle body on both my original and new in= takes. If I remember correctly, I believe I had a longer unused throttl= e travel with the original intake but I never measured it. I don't know= the static rpm increase with the new intake - probably have that in my no= tes some where but my max. rpm at high altitude (8,000 - 10,000) increased= 400-500 rpm. I estimated I went from 165 -170 HP with the old intake to= about 185 HP with the new intake. This in in line with Ed Anderson's rec= ent note that Mazda got about a 16% power increase at 6000 rpm with the DI= E effect. I felt much improved acceleration the first time I took off wit= h the new intake.=20 the new intake is based on dynamic intake effect (DIE) where the closing= of an intake valve caused the moving intake air to bounce off the valve= creating a pressure wave. The wave travels at the speed of sound to the= other intake valve and arrives there just before that valve closes. This= increases the amount of air and fuel that enters the combustion chamber.= (As we know the rotary has no valves but uses the sides of the rotor for= opening and closing the intakes.) I designed my intake to give max. perf= ormance at 6300 rpm. If I had cut down my prop to 74" it would give me more clearance for the= prop on my RV-7A and increase my top end rpm. Max rpm is about 6400 rpm= with the new intake and the 76" prop. I'm really not needing higher RPM= now. Dennis Haverlah Bill Bradburry wrote: Dennis, Did your static rpm increase with the new manifold? How much? Did you be= fore and do you now have any unused throttle travel like Mike describes?= Are you using the same throttle body on the new manifold? What is the= MM opening of the Mustang body? My manifold is very similar to your old one. My tubes are cut just above= the injector bosses, which makes them a little (maybe an inch) shorter th= an your old ones. I have a 76 X 88 Performance prop which I am considerin= g having cut down to 74=E2=80=9D like Tracy and Ed when I send it in for= final finish. I am using an aftermarket throttle body that is 75MM in th= roat diameter. This is the same size as the stock Renesis throttle body= which is why I picked it. I had intended to use the Renesis body, but di= dn=E2=80=99t wait for Tracy to get the fly by wire done. I am not flying,= but my static is 52-5300 rpm and I have a lot of throttle left at that rp= m. The last probably =C2=BC of the travel is not used. Bill B =20 =20 __________ Information from ESET NOD32 Antivirus, version of virus signatu= re database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ----------MB_8CC7B48EF200831_8A50_1DCEB_webmail-d096.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
George;
You were discussing (earlier) the effect oil temp has on volumetric= efficiency, namely that oil temps of 160 are cool enough to alow a good= air charge to enter the chamber, but higher oil temps caused rapid adiaba= tic expansion of the air, reducing air density, reducing power. Is th= at an acceptable summary?
Anyway, I was looking at the direct injected 16b engine depicted on= PL's site, and had to wonder?? would this fuel spray cool the intake air= charge via direct contact cooling fast enough to increase charge density= and vaporize the fuel better too? (win-win)?
Especially in a P Port engine?
Just wondering
Scott



-----Original Message-----
From: George Lendich <lendich@aanet.com.au>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Sat, Feb 13, 2010 1:20 pm
Subject: [FlyRotary] Re: Throttle limits was Re: N.A. Renesis to turbo

Bill,
I have stated this before and I will gain= , my calculations indicate a 44mm inlet ( per rotor) being the size needed= to 7,500 rpm - giving max inlet velocity ( of 100/120 mph). It wasn't unt= il I seen that the Powersport PP inlet tubes were 44mm that I was reassure= d I was on the right track. Others that we know push for the 3" ( 75mm) TB= , such as the Renesis TB, nice that it is.
 
Not many builders will go to 7,500 rpm so= 44mm is slightly overkill.
Probably could go as low as 38 to 40mm fo= r lower RPM, but I would have to crunch the numbers. At the time I was thi= nking I would have to go to 7,500 RPM on the single rotor to get max take-= off performance, so worked with those numbers. Of course the lower the inl= et diameter the higher the velocity and the better the VE.
 
Lynn spoke of 38mm and 44mm chokes, If I= remember correctly and chokes they are in his racing application&nbs= p;of much higher rpm, but the trade-off is inlet velocity.
 
I know one of the ex-Powersport people ar= e making ( machining) 44mm PP with 2 piece inlet tubes and fitting th= em to housings with O rings. I believe this service is available to anyone= interested. Information passed to me was that Powersport never had any se= aling problems after they went to this arrangement. Believe you me, they= spent a fortune on development.
 
I'm just wondering how I'm going to get= my housing over there to get it done.
George ( down under) 

Ed,
This throttle body= size thing came as a surprise to me a couple of years ago when I first st= arted my engine.  I selected the 75MM size because that was what was= in the RX-8 car.  It pretty obviously is way too large for our appli= cation.  Apparently even the 65 MM that Dennis is using appears to be= too large.  I suppose that is because in the car, the engine can rev= to 8K+ rpms.  We are only revving in the 5-6K range with an occasion= al outlier up in the low 7K range.  The fact that the car can rev so= high, I suppose, is the reason that there are no complaints about dead pe= dal in the car.
Thanks to you, I fee= l I now understand what is causing the phenomenon.  I don=E2=80=99t= see that it is a problem that should be fixed, at least, not yet. = I just need to work on getting the engine to produce the most power it ca= n and then, maybe, resize my prop to get rpms in a good power band for tak= eoff.
 =
It seems that I reme= mber someone on the list (probably Lynn) talking about a couple of carb th= roats being 44MM that he uses.  If so, they (two of them) would have= an area of about 3040 MM.  A single 65 MM body would have an area of= 3317 MM.. an increase of over 9%.  A 75 MM body would have an area= of 4415 MM=E2=80=A6a whopping 45% increase!
 =
Bill B=
 =
 =
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]= On Behalf Of Ed Anderson<= br> Sent: Friday, February 12,= 2010 4:38 PM
To: Rotary motors in aircr= aft
Subject: [FlyRotary] Throt= tle limits was Re: N.A. Renesis to turbo=
Bill, if Dennis had= a TB just big enough &nbs= p;that it exactly provided 100% power= at sea level, then as he increases in altitude, he will find= more and more throttle travel that does nothing to increase power. = This is because it takes less and less throttle plate opening to provide= sufficient airflow for the pressure/air density in the manifold to reach= the ambient pressure/air density (ambient density is decreasing with alti= tude).  Since that air density is less than at sea level, it requires= less throttle opening to reach than at sea level.
 
The position of the= throttle plate affects only the air flow volume (not the density of that= air airflow), but the amount of air flow volume does determine the air de= nsity in the manifold.  The external atmospheric pressure is of cours= e what is forcing the air through the throttle body =E2=80=93 The less air= pressure at altitude means less air is flowing through the TB as you gain= altitude.  Remember even though to simply the verbiage - we often ta= lk of the engine =E2=80=9Csucking=E2=80=9D but of course it does not. = ; The engine simply opens its ports and whatever pressure is in the manifo= ld  forces that air into the essentially empty combustion chamber.
 
Think of it this wa= y, there are two ways you can have ambient air density in your intake mani= fold. Those two ways are with the throttle open or the throttle closed =E2= =80=93 a contradiction?  Not, so.  You may have ambient air pres= sure/density in the manifold when the engine is running and TB open suffic= iently to provide ambient pressure in the manifold OR when the engine is not running.<= /div>
 
When the engine is= stopped - you also have ambient pressure in your intake even with your th= rottle 99.99 % closed because the engine is not =E2=80=9Csucking=E2=80=9D= any air out of the manifold when stopped.  So a small leak in the th= rottle bottle is sufficient for the manifold pressure to reach and maintai= n ambient when the engine is not running.
 
What Dennis has don= e with his DIE intake does not change this factor, but what the pulse in= the intake does when it reaches the other end of the intake manifold (not= e how his intakes are tied together so the pulse can travel from one intak= e port of one rotor to the intake port of the second rotor) is briefly cre= ate a localized pressure increase in the intake manifold right at the inta= ke port as it is open.  This in effect shoves more mixture into the= combustion chamber =E2=80=93 in effect it is a very brief supercharger ef= fect.  It only lasts for milliseconds and therefore you don=E2=80=99t= get the same power increase that you would if you had a turbocharger push= ing in denser air the entire time the intake is open.   On the= other hand you don=E2=80=99t have 30-50 lbs more weight and for basically= no more than fabricating your intake different =E2=80=93 it=E2=80=99s bas= ically a free lunch.
 
 But, as Denni= s will tell you - doing the analysis to get the equations so you get dimen= sion correct for the effect =E2=80=93 can give you a headache {:>) =E2= =80=93 right Dennis??.
 
So, anyhow, back th= e throttle travel, if your TB is larg= er than needed to reach 10= 0% power at sea level, then you would also find =E2=80=9Cexcess= =E2=80=9D throttle travel sitting on the ground with the engine running at= WOT.  Once the throttle is opened sufficient for manifold pressure= to reach ambient, then opening it further will provide no increase in pow= er.  You have in the vernacular- =E2=80=9CMaxed Out!=E2=80=9D {:>)
 
Once the throttle= plate is open sufficient to permit the manifold pressure/air density to= reach ambient conditions =E2=80=93 no further opening will produce any mo= re power even though you may have 5=E2=80=9D of throttle travel and 50% mo= re throttle plate opening to go.
 
 
 
Ed
 
 
 
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
From:mailto:flyrotary@lancaironline.net] On Behalf Of Bill Bradburry
Sent: Friday, February 12,= 2010 3:33 PM
To: Rotary motors in aircr= aft
Subject: [FlyRotary] Re:= rpm vs Power was : Throttle limits was Re: N.A. Renesis to turbo<= /div>
 
Thanks, Dennis,
It sounds like you still have a little= unused throttle travel even with the new intake.
Can you provide design measurements for= your new intake?  I ask only if you have no plans to make and sell= it.
 
Bill B 
 
From: Rotary motors in ai= rcraft [mailto:flyrotary@l= ancaironline.net] On Behalf Of Dennis Haverlah
Sent: Friday, February 12,= 2010 2:20 PM
To: Rotary motors in aircr= aft
Subject: [FlyRotary] Re:= rpm vs Power was : Throttle limits was Re: N.A. Renesis to turbo
I used= the same 65 mm Mustang throttle body on both my original and new intakes.=   If  I remember correctly, I believe I had a longer  unuse= d throttle travel with the original intake but I never measured it. = I don't know the static rpm increase with the new intake - probably have= that in my notes some where but my max. rpm at high altitude (8,000 - 10,= 000) increased 400-500 rpm.  I estimated I went from 165 -170 HP with= the old intake to about 185 HP with the new intake.  This in in line= with Ed Anderson's recent note that Mazda got about a 16% power increase= at 6000 rpm with the DIE effect.  I felt much improved acceleration= the first time I took off with the new intake.

the new intake is based on dynamic in= take effect  (DIE) where the closing of an intake valve ca= used the moving intake air to bounce off the valve creating a pressure wav= e.  The wave travels at the speed of sound to the other intake valve= and arrives there just before that valve closes.  This increases the= amount of air and fuel that enters the combustion chamber.  (As we= know the rotary has no valves but uses the sides of the rotor for opening= and closing the intakes.)  I designed my intake to give max. perform= ance at 6300 rpm.

If I had cut down my prop to 74" it would give me more clearance for the= prop on my RV-7A and increase my top end rpm.   Max rpm is abou= t 6400 rpm with the new intake and the 76" prop.  I'm really not need= ing higher RPM now.

Dennis Haverlah

Bill Bradburry wrote:
Dennis,
Did your static rpm increase with the= new manifold?  How much?  Did you before and do you now have an= y unused throttle travel like Mike describes?   Are you using th= e same throttle body on the new manifold?  What is the MM opening of= the Mustang body?
My manifold is very similar to your old= one.  My tubes are cut just above the injector bosses, which makes= them a little (maybe an inch) shorter than your old ones.  I have a= 76 X 88 Performance prop which I am considering having cut down to 74=E2= =80=9D like Tracy and Ed when I send it in for final finish.  I am us= ing an aftermarket throttle body that is 75MM in throat diameter.  Th= is is the same size as the stock Renesis throttle body which is why I pick= ed it.  I had intended to use the Renesis body, but didn=E2=80=99t wa= it for Tracy to get the fly by wire done.  I am not flying, but my st= atic is 52-5300 rpm and I have a lot of throttle left at that rpm. = The last probably =C2=BC of the travel is not used.
Bill B
 
 =


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The message was checked by ESET NOD32 Antivirus.

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