Date:         Wed, 17 Mar 2004 22:53:06 -0500
Reply-To:     David Brodbeck <gull@GULL.US>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Brodbeck <gull@GULL.US>
Subject:      Re: User friendly fuels (was you fixed it..)
Comments: To: David Beierl <dbeierl@ATTGLOBAL.NET>
In-Reply-To:  <5.1.0.14.2.20040317171412.04dcd3e0@pop1.attglobal.net>
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Wed, 17 Mar 2004, David Beierl wrote:

> Turbines, though, like ship propulsion plants.  Steam turbines in railroad
> service haven't worked out too well (understatement) because of dirt and
> vibration problems.

Well, there's that, and turbines have some serious disadvantages for rail
use.  They require expensive precision reduction gears to gear them down
to wheel speeds, they can't be throttled efficiently except over a small
range, and they can't run in reverse.  Most of those problems disappear if
you use them as part of an electric drivetrain, but it's awfully hard to
beat the efficiency of a low-speed diesel engine.

Turbines make more sense in ships and airplanes.  Both tend to run their
engines continuously at a high percentage of total available power.
Airplanes can't back up, and ships can carry smaller reversing turbines.


David Brodbeck, N8SRE
'82 Volkswagen Diesel Westfalia
'86 Volvo 240DL wagon