Return-Path: Received: from rokland5.awh.us ([67.15.10.31] verified) by logan.com (CommuniGate Pro SMTP 4.3c1) with ESMTP-TLS id 724591 for flyrotary@lancaironline.net; Thu, 10 Feb 2005 21:50:25 -0500 Received-SPF: none receiver=logan.com; client-ip=67.15.10.31; envelope-from=bob@bob-white.com Received: from bgp01386375bgs.brodwy01.nm.comcast.net ([68.35.160.229]:34144 helo=quail) by rokland5.awh.us with smtp (Exim 4.43) id 1CzQsD-0007VD-LO for flyrotary@lancaironline.net; Thu, 10 Feb 2005 20:49:37 -0600 Date: Thu, 10 Feb 2005 19:49:35 -0700 From: Bob White To: "Rotary motors in aircraft" Subject: Rotary Displacement, Was: Solved!!!! => Rotary AirFlow Equation? Help? Message-Id: <20050210194935.1de44cff.bob@bob-white.com> In-Reply-To: References: X-Mailer: Sylpheed version 1.0.1 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Antivirus-Scanner: Clean mail though you should still use an Antivirus X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - rokland5.awh.us X-AntiAbuse: Original Domain - lancaironline.net X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - bob-white.com X-Source: X-Source-Args: X-Source-Dir: I would like to interject a point here that I tried to make on the other list with little effect. All the bickering about what the "real" displacement for the rotry is is based on trying to make it "equilivent" to a 4-stroke, or a 2-stroke, or a ???. If I want to know the displacement of any piston engine I would calculate a volume based on the bore and stroke, multiply by the number of the pistons, and I would have the displacement. Mazda decideded the engine was a 1.3 liter for tax reasons. Various racing orginizations have numbers they calculate, etc. Displacement doesen't have anything to do with RPM, it's just how much does the engine displace! In operation, the 2-stroke "uses" it's displacement in 1 revolution, the 4-stroke in 2 revolutions, and the rotary in 3 revolutions of the E-shaft or one revolution of the rotors. In all these cases, the engine has gone thru one complete cycle and is in exactly the same state it started in. I'm not saying these discussions are not meaningful, because the intent is to know how to compare the rotary with a different engine geometry. But when the insurance company wanted to know what size my engine was, I calculated the "actual" displacement at 238 cu. in. If I had a 2.6 L 2-stroke engine, I wouldn't use an "equilivent" displacement so that it would match a 4-stroke so why would I do so for the rotary? That's my understanding, and Ed it looks to me like you've done a great job sorting thru the math. Bob White On Thu, 10 Feb 2005 19:41:42 -0500 WRJJRS@aol.com wrote: > Ed, > The problem here is that the formula used for displacement. The real > solution is that the racing sanctioning bodies want the rotary to be > at a slight disadvantage to piston engines! It, (the formula), has no > relation to actual reality! > Bill Jepson > > -- http://www.bob-white.com N93BD - Rotary Powered BD-4 (soon)