X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from tomcat.al.noaa.gov ([140.172.240.2] verified) by logan.com (CommuniGate Pro SMTP 4.3.4) with ESMTP id 1008269 for flyrotary@lancaironline.net; Mon, 20 Jun 2005 20:07:30 -0400 Received-SPF: none receiver=logan.com; client-ip=140.172.240.2; envelope-from=bdube@al.noaa.gov Received: from mungo.al.noaa.gov (mungo.al.noaa.gov [140.172.241.126]) by tomcat.al.noaa.gov (8.12.11/8.12.0) with ESMTP id j5L06hHi024419 for ; Mon, 20 Jun 2005 18:06:43 -0600 (MDT) Message-Id: <6.2.1.2.0.20050620175823.03e91760@mailsrvr.al.noaa.gov> X-Mailer: QUALCOMM Windows Eudora Version 6.2.1.2 Date: Mon, 20 Jun 2005 18:05:37 -0600 To: "Rotary motors in aircraft" From: Bill Dube Subject: Re: [FlyRotary] Re: Fuel Injector Position In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed > >It would be interesting to try putting only the secondaries at a distance, >and make the staging point as high as you can. This would give you a nice >cooling of the intake charge under full throttle ops, but maybe (key word) >not hurt throttle response that much. I don't think this helps charge density. Indeed, by giving the fuel a chance to fully evaporate in the manifold you cool the air. The fuel vapor occupies much more space than the fuel droplets. Thus, the resultant cold air / fuel vapor combo is less dense than the warm air / fuel droplets combo. By locating the injectors close to the engine, a good fraction of the fuel is still in the form of tiny droplets, which occupy much less space than fuel vapor. Thus, you end up with a greater charge density. At least this is the way I understand it to be. Bill Dube'