Passenger schedules

[NW Mailing List]

The reason behind the increase in pressure is one based on thermodynamics.
In short, the engine becomes more thermally efficient and more of the heat
energy put into the steam can be recovered for mechanical work under the
conditions of higher pressure- an increase in 'enthalpy'.  Hence, the
savings in coal and water usage as mentioned by Dave.  

Gary Rolih
Cincinnati

 
-----Original Message-----
From: nw-mailing-list-bounces at nwhs.org
[mailto:nw-mailing-list-bounces at nwhs.org] On Behalf Of NW Mailing List
Sent: Monday, October 26, 2009 7:05 AM
To: NW Mailing List
Subject: Re: Passenger schedules

A test report at the archives indicates that N&W was interested in operating
economy when considering raising the J's boiler pressure from 275 psi to 300
psi.  There was a measurable savings in coal and water per unit of output at
the higher pressure. 

Dave Stephenson




      
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