Did this improve performance? Streamlined King + Castle

If you care to look closely at current trains you will see a lot of streamlining details, curved front, rounded front to side connections, streamlining below the buffers, smooth windows and the like. It is not just about a windbreaking nose but avoidance of useless friction and vortices.
Kind regards
Jos Koopmans

 

It is the avoidance of (or more feasibly the delay of) flow separation and of vortex shedding which is most important in energy conservation. The nose is much less important than people think. People knew this in the 1930s, which is why both Gresley and Stanier designed streamlined TRAINS to go behind their locos.

 

You could even hypothesise that a flat fronted diesel like a 47 or 50 would be more aerodynamically efficient in conjunction with a passenger train than the more rounded looking Deltic, because it's got a flat cab at both ends, and thus blends into the train better. It might be an interesting experiment. The American streamlined diesels were all single cab with a flat back end.

Speaking of aerodynamic shapes of modern trains compared to the streamliner era, does anyone else think that the class 180 DMUs have a nose quite reminiscent of a Bugatti railcar?

 

So it's entirely logical that the only single ended 'locomotives' (with seating in them) of the 60s should have been the only streamlined ones (the Blue Pullmans).

On a different subject the GWR's reputed original streamliner, or 'windcutter' of the 1830s could hardly have been dictated by fashion! While both aesthetically and practically it was even less successful than Manorbier Castle.

 

Plus speeds in the US were not especially high, negating the energy-saving benefits of streamlining anyway, and fuel was cheap. I'm sure that a large part of the design of early US streamlined diesels was about presenting a "modern" image rather than fuel saving. To a large extent, the railways were in competition with air travel, which was itself the height of modernity in the 1930s.

Tom

 

In addition it was both cheaper and lighter to have a single cab than to have two. These factors still apply today. In Oz, we have/had US style streamliners built to both US and UK designs. Modern locomotives being delivered in Australia have one cab, again cost is the factor along with the capability to MU with a second unit facing backwards, as per the UP picture above.

 

In general, no, but there were a few trains operating regularly at speeds every bit as high or higher than the contemporary UK streamliners.
However the great majority of US streamliners (steam and diesel) were for show only. But some of them looked great, so who's complaining?

 

The Penn T1 was designed for high speed. Streamlining by Loewy is distinctly different from UK shapes, more like a ships bow, so that no massive amounts of air pass the chimney and hamper the exhaust. Note that a replica of a T1 is in the making with the intention to take away Mallards record.
Kind regards
Jos Koopmans

 

I preferred his earlier bullet nose design for the big S1, in my opinion the best looking of all the American streamliners.

Unfortunately the T1 project seems to have gone somewhat quiet of late.

 

Got to say, that's an impressive beast. What was the thinking behind the arrangement of the cylinders and driving wheels though? Would it not have been better for adhesion to have had eight coupled wheel driving traction instead of two sets of fours?

 

They cast their first Boxpok wheel just over a month ago, could not have been that quiet!
Kind regards
Jos Koopmans

 

Presumably as well with a somewhat generous US loading gauge, you can make outside cylinders bigger than inside ones (where you have the same constraints as in the UK with respect the space between frames and therefore on maximum cylinder diameter). So that arrangement of four cylinders allows more power and TE than an otherwise equivalent four cylinder design with two inside and two outside cylinders.

Edit: with regard slipping, the ratio of adhesion:TE is 4.32 (figures from Wikipedia). That is not particularly extreme, about equivalent to a 9F. A Maunsell Schools has a figure of 3.74, which is about the lowest I know of in the UK. (A low figure means the TE is high relative to the adhesion, so potentially more prone to slipping. Other factors also apply!).

Tom

 

Good question. I can understand the rationale behind the big US articulators as you're in effect getting two locos for the price of one and the ability to negotiate curves much better than a loco with a long fixed wheelbase but the Pennsy duplex locos were a fixed wheelbase so perhaps it was a way of getting four cylinders without having any inside the frames. The could be notorious slippers though if not handled properly so I have read.

Edit : Sagging Dragon has already proposed this.

 

See https://en.wikipedia.org/wiki/PRR_T1#/media/File:The_T1_Trust_Boxpok_Driver.jpg

Tom

 

Imagine those big drivers letting loose at 120 mph plus. Could make Blue Peter's little incident look like a minor inconvenience.