X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from aspensprings.uwyo.edu ([129.72.10.32] verified) by logan.com (CommuniGate Pro SMTP 5.3.7) with ESMTPS id 4341140 for flyrotary@lancaironline.net; Wed, 09 Jun 2010 02:54:48 -0400 Received-SPF: none receiver=logan.com; client-ip=129.72.10.32; envelope-from=SBoese@uwyo.edu Received: from ponyexpress-ht1.uwyo.edu (ponyexpress-ht1.uwyo.edu [10.84.60.208]) by aspensprings.uwyo.edu (8.14.2/8.14.2) with ESMTP id o596s9C7016480 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Wed, 9 Jun 2010 00:54:10 -0600 (MDT) (envelope-from SBoese@uwyo.edu) Received: from ponyexpress-mb5.uwyo.edu ([fe80::9813:248c:2d68:a28b]) by ponyexpress-ht1 ([10.84.60.208]) with mapi; Wed, 9 Jun 2010 00:54:09 -0600 From: "Steven W. Boese" To: Rotary motors in aircraft Date: Wed, 9 Jun 2010 00:54:09 -0600 Subject: RE: [FlyRotary] Re: high/low pressure pumps question Thread-Topic: [FlyRotary] Re: high/low pressure pumps question Thread-Index: AcsHmAdPoGsFZXLrQ2+FGdSYG3nPyQABtWEM Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C78ponyexpressmb_" MIME-Version: 1.0 --_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C78ponyexpressmb_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Todd, Since the bubbles disappear and the circulating liquid becomes clear after = prolonged circulation of a small volume of gasoline , I think the bubbles w= ere not gasoline vapor since the system is still circulating gasoline. Whe= n I worked as a chemist, we would remove air from solvents used in high pre= ssure liquid chromatography by passing the solvent through a vacuum filtrat= ion apparatus which also entalis a high to low pressure transition. This r= emoved the dissolved air more quickly and thoroughly than sparging the solv= ent with helium. Steve Boese RV6A, 1986 13B NA, RD1A, EC2 ________________________________ From: Rotary motors in aircraft [flyrotary@lancaironline.net] On Behalf Of = Todd Bartrim [bartrim@gmail.com] Sent: Tuesday, June 08, 2010 11:38 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: high/low pressure pumps question Steve; I believe the bubbles you are seeing in the line is very likely the eva= porative emissions, that resulted in the development of the return-less fue= l system. I also have never seen foaming in gasoline, but diesel on the other han= d, can foam easily. So unless Jet fuel is in the plans I wouldn't worry abo= ut that. Todd -----Original Message----- From: Steven W. Boese > Reply-To: Rotary motors in aircraft > To: Rotary motors in aircraft > Subject: [FlyRotary] Re: high/low pressure pumps question Date: Tue, 8 Jun 2010 13:33:19 -0600 Kelly, When the statement was made that the air would eventually be elimi= nated through the vent, I didn't mean to imply that it was necessary to hav= e this happen. It would be best to avoid drawing the bubbles directly into= the fuel supply line which would only happen if the fuel was returned very= close to the supply inlet. On one wing tank, I have the return entering = center of the root rib about a foot away from the supply inlet. For the ot= her tank, the return outlet is next to the filler cap which is always above= the fuel level and as far away from the supply inlet as is possible. No d= ifference in operation of the two tanks has been noticed. A reason given = for returning the fuel below the liquid level has been to reduce foaming. = There may be other reasons. I haven't seen much tendency for gasoline to f= oam under conditions present in my system. Steve Boese RV6A, 1986 13B NA,= RD1A, EC2 ________________________________ From: Rotary motors in aircraft [flyrotary@lancaironline.net] On Behalf Of = Kelly Troyer [keltro@att.net] Sent: Tuesday, June 08, 2010 11:26 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: high/low pressure pumps question Guys, Very enlightening and truly food for thought to those of us still i= n the construction stage...........I have just one more question to ask....= ........Previous info seemed to indicate that return fuel should be enterin= g the fuel tank at the bottom or at least close to the bottom.............I= n light of Steve's observations would it seem reasonable that air bubbles i= n the return fuel would be eliminated to the tank vent faster if the return= line was at the top or close to the top of the tank ??................ Kelly Troyer "Dyke Delta"_13B ROTARY Engine "RWS"_RD1C/EC2/EM2 "Mistral"_Backplate/Oil Manifold --_000_E1AA3B1AF41D8049B1E3FBD5E225626004D4FE7C78ponyexpressmb_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
Todd,
 
Since the bubbles disappear and the c= irculating liquid becomes clear after prolonged circulation of a small= volume of gasoline , I think the bubbles were not gasoline vapor since the= system is still circulating gasoline.  When I worked as a chemist, we would remove air from solvents used in high pres= sure liquid chromatography by passing the solvent through a vacuum filtrati= on apparatus which also entalis a high to low pressure transition.  Th= is removed the dissolved air more quickly and thoroughly than sparging the solvent with helium. 
 
Steve Boese
RV6A, 1986 13B NA, RD1A, EC2
 
From: Rotary moto= rs in aircraft [flyrotary@lancaironline.net] On Behalf Of Todd Bartrim [bar= trim@gmail.com]
Sent: Tuesday, June 08, 2010 11:38 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: high/low pressure pumps question

Steve;
    I believe the bubbles you are seeing in the line is very= likely the evaporative emissions, that resulted in the development of the = return-less fuel system.
    I also have never seen foaming in gasoline, but diesel o= n the other hand, can foam easily. So unless Jet fuel is in the plans I wou= ldn't worry about that.

Todd


-----Original Message-----
From: Steven W. Boese <SBoese@uwyo.edu>
Reply-To: Rotary motors in aircraft <flyrotary@lancai= ronline.net>
To: Rotary motors in aircraft <flyrotary@lancaironlin= e.net>
Subject: [FlyRotary] Re: high/low pressure pumps question
Date: Tue, 8 Jun 2010 13:33:19 -0600


Kelly,  = When the statement was made that the air would even= tually be eliminated through the vent, I didn't mean to imply that it was n= ecessary to have this happen.  It would be best to avoid drawing the b= ubbles directly into the fuel supply line which would only happen if the fuel was returned very close to the supply = inlet.   On one wing tank, I have the return entering center= of the root rib about a foot away from the supply inlet.  For the oth= er tank, the return outlet is next to the filler cap wh= ich is always above the fuel level and as far away from the supply inlet as is= possible.  No difference in operation of the two tanks has been notic= ed.   A reason given for returning the fuel below the liquid level has b= een to reduce foaming.  There may be other reasons.  I haven= 't seen much tendency for gasoline to foam under conditions present in my system.   Steve Boese RV6A, 1986 13B NA, R= D1A, EC2     

From: Rotary motors in aircraft [flyrotary@lanc= aironline.net] On Behalf Of Kelly Troyer [keltro@att.net]
Sent: Tuesday, June 08, 2010 11:26 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: high/low pressure pump= s question




Guys,   Very en= lightening and truly food for thought to those of us still in the cons= truction stage...........I have just one more question to ask............Previous info s= eemed to indicate that return fuel should be entering the fuel tank at the bottom or at least close to the bo= ttom.............In light of Steve's observations would it seem reasonable that air bubbles in the return= fuel would be eliminated to the tank vent faster if the return line was at the top or close to the top of the tank= ??................  
  Kelly Troyer<= /font>
"Dyke Delta"_13B ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold <= br>

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