X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from QMTA04.westchester.pa.mail.comcast.net ([76.96.62.40] verified) by logan.com (CommuniGate Pro SMTP 5.2c1) with ESMTP id 2607056 for flyrotary@lancaironline.net; Thu, 20 Dec 2007 12:50:05 -0500 Received-SPF: none receiver=logan.com; client-ip=76.96.62.40; envelope-from=gregw@onestopdesign.biz Received: from OMTA06.westchester.pa.mail.comcast.net ([76.96.62.51]) by QMTA04.westchester.pa.mail.comcast.net with comcast id T3KY1Y00B16LCl0050BU00; Thu, 20 Dec 2007 17:49:26 +0000 Received: from gregoryii ([24.6.40.29]) by OMTA06.westchester.pa.mail.comcast.net with comcast id T5pQ1Y00L0dkeQQ3S00000; Thu, 20 Dec 2007 17:49:26 +0000 X-Authority-Analysis: v=1.0 c=1 a=Wj5LLpRhAAAA:8 a=oQl2_OypAAAA:8 a=7g1VtSJxAAAA:8 a=Ia-xEzejAAAA:8 a=N8B9JuSIAAAA:8 a=Y6dYij8W7cSRb9nBHysA:9 a=uISWOhreumcNucC4g7gA:7 a=sEz-OhNb5BWQRtE9egkKklRcrdUA:4 a=MSl-tDqOz04A:10 a=eJojReuL3h0A:10 a=EzXvWhQp4_cA:10 a=gi0PWCVxevcA:10 a=pdWnb-WGOBYNskJr7-AA:9 a=92vCjcHcCatWXwi3lH0A:7 a=B1ktj4Cvmwdp_ceUdoGc_bKnAzYA:4 a=i5qLLpNwen0A:10 a=AfD3MYMu9mQA:10 Message-ID: <085801c84332$1a728e00$8801a8c0@yosemite.onestopdesign.biz> From: "Greg Ward" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Supercharging Date: Thu, 20 Dec 2007 09:59:43 -0800 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0855_01C842EF.0B94FEB0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 This is a multi-part message in MIME format. ------=_NextPart_000_0855_01C842EF.0B94FEB0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I agree, interesting. Sent them a s....pile of questions, awaiting a = reply, will forward. The ones on Ebay look like plastic junk. Greg ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Thursday, December 20, 2007 8:25 AM Subject: [FlyRotary] Re: Supercharging Interesting find, David. =20 I must admit after seeing all of those squirrel cage fan "electric = superchargers" advertised for $59.99 on E bay and else where back a few = years ago (and perhaps even today) - I was very skeptical of what I = would see here. I also could not find any technical specifications or = compressor map on the website - and that does not lessen my skeptical = feeling.=20 However, from the forum "testimonials" in which several folks have = dynoed the results as well as collected other parameters, I must admit = it appears there is some validity to the claims or else they are somehow = fooling a lot of folks {:>). It appears to take between 700 and 1100 watts of power from what data = I could find. So Power =3D Current*Voltage. The current would then I = =3D Power/Voltage =3D 1100/12 =3D 91 amps, or 700/12 =3D 58 amps. So = the current draw may depend on the model but would appear to range from = 58 - 91 amps or around 1 - 1.4 HP. So a fully charged battery would = probably power it for 5-10 minutes - perhaps longer, you could get more = precise interval by looking up the Reserve Capacity of your battery.=20 I must admit that for the price it is tempting just to get one and = play with it - However, I have not seen anywhere mention of its weight. = From the electric motors I have seen, - a 1 - 1.4HP electric motor can = be huge and heavy. Now this is surely a smaller/lighter weight motor = than those heavy weighs. I forget my DC motor types, but as best I = recall there is one referred to as a series winding that simply keeps = spinning faster (and drawing lots of current) until it meets its load = limit (or flies apart). But again no specifications that I could find. So putting aside my skepticism (for the moment) I would think for = aircraft use you would probably want a second battery you could dedicate = to powering the superchargers electric motor for a several minutes. = Hummm, where did I put that second battery case, I took out of my = aircraft.=20 I would certainly want to know how long the motor could stand the load = and heat. It does not appear this is meant for sustained boost, just = for getting your Mustang from 0-60 quickly then off the boost. But, = having 30 more HP for take off and initial climbout for 3-5 minutes = could be nice to have. Then the next question is how much effect it has = on the air flow to your engine when it is not under power. Eliminating = the need for hot exhaust gas and water coolant lines would be also be a = plus. Could not tell whether it required any tie in to the engines = lubrication system - one would presume so, but there was a turbocharger = sold for a while that had its own oil reservoir. And of course what does = it weigh? Still for $100 it might be interesting to experiment with. But, I'll = wait a bit - no mention of problems on the site, but also no mention of = life cycles or hours of run time. Still a bit skeptical, when I don't = see any specifications on a website, but willing to suspend it for a = while {:>) Ed ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Thursday, December 20, 2007 9:06 AM Subject: [FlyRotary] Re: Supercharging Google place this ad for electric superchargers on the last post. = At least it is designed for an engine.. http://www.electricsupercharger.net/ Dave Leonard On Dec 20, 2007 6:02 AM, Thomas Jakits = wrote: Here a another interesting bit on the screw type charger "wars": http://www.svtsnake.com/forum/archive/index.php/t-1387.html=20 Obviously one must do his homework before deciding on one.=20 However the design seems superior to the roots anyway ....=20 TJ On Dec 19, 2007 11:15 PM, Ed Anderson < eanderson@carolina.rr.com> = wrote: ----- Original Message -----=20 From: "Charlie England" To: "Rotary motors in aircraft" =20 Sent: Wednesday, December 19, 2007 10:47 PM Subject: [FlyRotary] Re: Supercharging > Ernest Christley wrote: >> David Leonard wrote: >>>> 6000RPM is about the speed that commercial leaf blowers = use. The >>>> blowers just happen to be about the same size as an engine = housing. A >>>> conservative blower will easily deliver 600 CFM at 150MPH. >>>> =20 >>> >>> >>> Somehow we are going to have to connect the blower to the = drive=20 >>> chain. That >>> is either going to be a belt (with pullys we can size = however we want) or >>> some sort of gear. Either way, everyone will have a blower = running=20 >>> the rpm >>> they need, no advantage (or disadvantage) to the rotary = running at=20 >>> 6000 rpm. >>> >>> >>> =20 >>=20 >> What if you replace the flywheel with the fan from the = blower? No=20 >> gears. No belts. No chains. No heavy mounting to support = any of=20 >> them. The advantage of the rotary running at 6000 RPM is = that we don't=20 >> have to pull the power off and transfer it over to a = different=20 >> structure. We can mount the blower as an integral part of = the drive chain. >>> =20 >>>> We don't >>>> usually want a LOT of boost in an airplane, since that will = impact >>>> reliability, but how much is a LOT? >>>> =20 >>> >>> >>> True, not "a lot" by race standards, but if you just turbo = normalize you >>> WILL be using a lot of boost (by OEM standards) when above = 10000'. I=20 >>> could >>> easily max out my stock turbo at 14000. >> More power is always more better, but what deal with the = devil do you=20 >> have to make to get it? My project can't handle the weight = of a turbo=20 >> or a supercharger, and I personally don't want to deal with = the=20 >> complications of either. So I back off, accept less power as = the=20 >> penalty for doing less work. Can I get 10Hp for a couple = pounds on the=20 >> nose and a few more feet of intake plumbing? The answers = we've come up=20 >> with so far say that it is a definite 'maybe', with a solid = dose of 'it=20 >> depends'. Maybe I won't be able to completely normalize, but = I think I=20 >> should be able to increase my service ceiling. An alternate = air intake=20 >> will enable me to test to see just how much it increases. >>=20 >> --=20 >> Homepage: http://www.flyrotary.com/ >> Archive and UnSub: =20 >> http://mail.lancaironline.net:81/lists/flyrotary/List.html >>=20 >>=20 > A 'sanity check' (of the concept) might be in order. >=20 > How big is the 'fan' in the leaf blower (diameter & = thickness)? >=20 > How big is the 'fan' in a typical turbo for the rotary? >=20 > Is it likely that the 'fan' from the leaf blower can move as = much air=20 > against the same back pressure turning 6k rpm as the turbo = turning 100k rpm? >=20 > (A P-port will *reduce* weight as it adds HP. :-) ) >=20 > Charlie >=20 =20 Hi Charlie,=20 Flew past your place on Monday heading back from Louisiana, gave = a radio call but got no response and didn't have time to stop for a = visit. Regarding your suggestion/question. Part of the problem is that = the engine will always displace the same cubic inches per revolution. = Therefore, there are only two ways to get more power per revolution - = increase the density of the air or provide more oxidizer through a = chemical process such as Nitrous oxide. You simply can not force the = engine to produce more power per rev without doing one of the two - or = both. =20 A turbo compressor or supercharger has to compress (increase the = density of the air) without letting the higher pressure air (as a result = of increased density) flow backwards past the pump impellers from the = high pressure area to the low pressure area. The roots type blower does = this by acting as a positive displacement pump it self whereas the = centrifugal compressor simply uses the superfast spinning blades to beat = the air molecules from the low pressure area (intake) to the high = pressure area (manifold) and with such close tolerances that the air = molecules have difficulty overcoming the momentum of the air and trying = to flow back from the high pressure area against the spinning blades. So the reason the turbo and supercharger increase power for a = given rpm over an N/A engine is they increase the density of the air = not the velocity or volume - those are just side effects. The flow rate = will in fact appear to increase because the non compressed flow will = flow faster into the compressor's intake as the increase in density = after the compressor must come from additional airflow into the = compressor. However, the engine itself is still flowing the same cubic = feet/sec its displacement of course does not change - its just that its = combustion chamber is now packed with more air due to the higher = density. I certainly hope the experiment proves worthwhile - but, I must = admit I can not see how it is going to significantly increase power. = Whether the power addition is worth the effort will depend on how much = effort it requires for the gain. Just my 0.02 Ed --=20 David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net ------=_NextPart_000_0855_01C842EF.0B94FEB0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I agree, interesting.  Sent them a = s....pile of=20 questions, awaiting a reply, will forward.  The ones on Ebay look = like=20 plastic junk.
Greg
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Thursday, December 20, = 2007 8:25=20 AM
Subject: [FlyRotary] Re:=20 Supercharging

Interesting find, David.   =
 
I must admit after seeing all of those = squirrel=20 cage fan  "electric superchargers" advertised for $59.99 on = E bay=20 and else where back a few years ago (and perhaps even today)  - I = was=20 very skeptical of what I would see here.  I also could not find = any=20 technical specifications or compressor map on the website - and that = does not=20 lessen my skeptical feeling. 
 
 However, from the forum "testimonials" = in which=20 several folks have dynoed the results as well as collected other = parameters, I=20 must admit it appears there is some validity to the claims or else = they are=20 somehow fooling a lot of folks {:>).
 
It appears to take between 700 and 1100 watts = of power=20 from what data I could find.  So Power =3D Current*Voltage.  = The=20 current would then I =3D Power/Voltage =3D 1100/12 =3D 91 amps, or = 700/12 =3D 58=20 amps.  So the current draw may depend on the model but would = appear to=20 range from 58 - 91 amps or around 1 - 1.4 HP.  So a fully charged = battery=20 would probably power it for 5-10 minutes - perhaps longer, you could = get more=20 precise interval by looking up the Reserve Capacity of your battery.=20
 
I must admit that for the price it is tempting = just to=20 get one and play with it - However, I have not seen anywhere mention = of its=20 weight.  From the electric motors I have seen,  - a  1 = - 1.4HP=20 electric motor can be huge and heavy.  Now this is = surely  a smaller/lighter weight motor than those heavy = weighs.  I=20 forget my DC motor types, but as best I recall there is one referred = to as a=20 series winding that simply keeps spinning faster (and drawing lots of = current)=20 until it meets its load limit (or flies apart).  But again no=20 specifications that I could find.
 
So putting aside my skepticism (for the = moment)  I=20 would think for aircraft use you would probably want a second battery = you=20 could dedicate to powering the superchargers electric motor for a = several=20 minutes.  Hummm, where did I put that second battery case, I took = out of=20 my aircraft. 
 
I would certainly want to know how long the = motor could=20 stand the load and heat.  It does not appear this is meant for = sustained=20 boost, just for getting your Mustang from 0-60 quickly then off the=20 boost.  But, having 30 more HP for take off and initial climbout = for 3-5=20 minutes could be nice to have.  Then the next question is how = much effect=20 it has on the air flow to your engine when it is not under = power. =20 Eliminating the need for hot exhaust gas and water coolant lines would = be also=20 be a plus.  Could not tell whether it required any tie in to the = engines=20 lubrication system - one would presume so, but there was a = turbocharger sold=20 for a while that had its own oil reservoir. And of course what does it = weigh?
 
 
Still for  $100 it might be interesting = to=20 experiment with.  But, I'll wait a bit - no mention of problems = on the=20 site, but also no mention of life cycles or hours of run time.  = Still a=20 bit skeptical, when I don't see any specifications on a website, but = willing=20 to suspend it for a while {:>)
 
Ed
----- Original Message -----
From:=20 David=20 Leonard
To: Rotary motors in = aircraft=20
Sent: Thursday, December 20, = 2007 9:06=20 AM
Subject: [FlyRotary] Re:=20 Supercharging

Google place this ad for electric superchargers on = the last=20 post.  At least it is designed for an engine..

http://www.electricsupercha= rger.net/

Dave=20 Leonard

On Dec 20, 2007 6:02 AM, Thomas Jakits = <rotary.thjakits@gmail.com&g= t;=20 wrote:
Here=20 a another interesting bit on the screw type charger = "wars":

http://www.svtsnake.com/forum/archive/index.php/t-1387.ht= ml=20

Obviously one must do his homework before deciding on = one.=20
However the design seems superior to the roots anyway ....=20


TJ

On Dec 19, 2007 11:15 PM, Ed Anderson = < eanderson@carolina.rr.com> wrote:
 
----- Original Message -----
From: "Charlie England" <ceengland@bellsouth.net>
To: "Rotary motors in aircraft" = <flyrotary@lancaironline.net>
Sent: Wednesday, December 19, 2007 10:47 = PM
Subject: [FlyRotary] Re:=20 Supercharging

> Ernest Christley wrote:
>> = David=20 Leonard wrote:
>>>> 6000RPM is about the speed = that=20 commercial leaf blowers use.  The
>>>> = blowers just=20 happen to be about the same size as an engine housing. =20 A
>>>> conservative blower will easily deliver = 600 CFM at=20 150MPH.
>>>>    =20
>>>
>>>
>>> Somehow we are = going to=20 have to connect the blower to the drive
>>> = chain. =20 That
>>> is either going to be a belt (with pullys = we can=20 size however we want) or
>>> some sort of = gear.  Either=20 way, everyone will have a blower running
>>> the=20 rpm
>>> they need, no advantage (or disadvantage) to = the=20 rotary running at
>>> 6000=20 rpm.
>>>
>>>
>>>   =
>>
>> What if you replace the flywheel with = the fan=20 from the blower?  No
>> gears.  No = belts.  No=20 chains.  No heavy mounting to support any of
>>=20 them.  The advantage of the rotary running at 6000 RPM is = that we=20 don't
>> have to pull the power off and transfer it = over to a=20 different
>> structure.  We can mount the blower = as an=20 integral part of the drive chain.
>>> =20
>>>>  We don't
>>>> usually = want a=20 LOT of boost in an airplane, since that will = impact
>>>>=20 reliability, but how much is a=20 LOT?
>>>>    =20
>>>
>>>
>>> True, not "a = lot" by=20 race standards, but if you just turbo normalize = you
>>> WILL=20 be using a lot of boost (by OEM standards) when above = 10000'.  I=20
>>> could
>>> easily max out my stock = turbo at=20 14000.
>> More power is always more better, but what = deal with=20 the devil do you
>> have to make to get it?  My = project=20 can't handle the weight of a turbo
>> or a = supercharger, and I=20 personally don't want to deal with the
>> = complications of=20 either.  So I back off, accept less power as the =
>>=20 penalty for doing less work.  Can I get 10Hp for a couple = pounds on=20 the
>> nose and a few more feet of intake = plumbing?  The=20 answers we've come up
>> with so far say that it is a = definite=20 'maybe', with a solid dose of 'it
>> depends'.  = Maybe I=20 won't be able to completely normalize, but I think I =
>> should=20 be able to increase my service ceiling.  An alternate air = intake=20
>> will enable me to test to see just how much it=20 increases.
>>
>> --
>> = Homepage: =20 http://www.flyrotary.com/
>> Archive and UnSub:   =
>>=20 http://mail.lancaironline.net:81/lists/flyrotary/List.html
>>
>>
> A 'sanity check' (of the = concept)=20 might be in order.
>
> How big is the 'fan' in the = leaf=20 blower (diameter & thickness)?
>
> How big is = the 'fan'=20 in a typical turbo for the rotary?
>
> Is it likely = that=20 the 'fan' from the leaf blower can move as much air
> = against the=20 same back pressure turning 6k rpm as the turbo turning 100k = rpm?
>=20
> (A P-port will *reduce* weight as it adds HP. :-) = )
>=20
> Charlie
> 
 
 Hi = Charlie,
 
Flew past your place on Monday heading = back from=20 Louisiana, gave a radio call but got no response and didn't have = time to=20 stop for a visit.
 
Regarding your = suggestion/question.  Part of=20 the problem is that the engine will always displace the same = cubic=20 inches per revolution.  Therefore, there are only = two ways=20 to get more power per revolution - increase the density = of the=20 air or provide more oxidizer through a chemical process such as = Nitrous=20 oxide.  You simply can not force the engine to produce more = power=20 per rev without doing one of the two - or both.  =
 
A turbo compressor or supercharger has = to compress=20 (increase the density of the air) without letting the higher = pressure=20 air (as a result of increased density) flow backwards past the=20 pump impellers   from the high pressure area to = the low=20 pressure area.  The roots type blower does this by acting = as a=20 positive displacement pump it self whereas the centrifugal = compressor=20 simply uses the superfast spinning blades to beat the air = molecules from=20 the low pressure area (intake) to the high pressure area = (manifold) and=20 with such close tolerances that the air molecules have = difficulty=20 overcoming the momentum of the air and trying to flow back from = the high=20 pressure area against the spinning blades.
 
So the reason the turbo and supercharger = increase=20 power for a given rpm over an N/A engine is  they increase = the=20 density of the air not the velocity or volume - those are just = side=20 effects.  The flow rate will in fact appear to increase = because the=20 non compressed flow will flow faster into the compressor's = intake as the=20 increase in density after the compressor  must come from = additional=20 airflow into the compressor.  However, the engine itself is = still=20 flowing the same cubic feet/sec its displacement of course does = not=20 change  - its just that its combustion chamber is now = packed with=20 more air due to the higher density.
 
 I certainly hope the experiment = proves=20 worthwhile - but, I must admit I can not see how it is going to=20 significantly increase power.  Whether the power addition = is worth=20 the effort will depend on how much effort it requires for the=20 gain.
 
Just my 0.02
 
Ed
 
 
 
 
 
 

=


--
David Leonard

Turbo Rotary RV-6 = N4VY
http://N4VY.RotaryRoster.nethttp://RotaryRoster.net=20
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