Return-Path: Received: from [216.52.245.18] (HELO ispwestemail1.aceweb.net) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2644322 for flyrotary@lancaironline.net; Mon, 20 Oct 2003 22:02:32 -0400 Received: from 7n7z201 (unverified [209.206.0.170]) by ispwestemail1.aceweb.net (Vircom SMTPRS 2.1.268) with SMTP id for ; Mon, 20 Oct 2003 18:56:33 -0700 Message-ID: <0b2f01c39777$1b64d040$252dbbd0@7n7z201> From: "William" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Water pumps Somebody STOP me! Date: Mon, 20 Oct 2003 21:00:29 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MIMEOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Yes, as you throttle down a pump, you have less water going through it, but the motor is still pumping in power -- not as much as when you are letting water flow and doing work on it, but still significant. The difference between the power in, and the power put into the water by pumping it is transformed to heat, raising the temperature of the water. This can cause cavitation under some conditions, when you get to a suction pressure less thant the vapor pressure of the fluid. Bill Schertz ----- Original Message ----- From: > Forgive me for being slow here, but there are quite a few more lines on this graph than I'm used to. Does this graph say that as the head pressure rises to 100ft, it raises the water temp by about 40 degree,and yet uses nearly 10HP to do it? > Content-Type: multipart/alternative; > boundary="----=_NextPart_001_0A85_01C39682.B1BBDDE0" > >