Locomotive Front End Designs

Yes, but the point of evolution is that the vast majority of differences convey no advantage, or a positive disadvantage, and therefore are not selectively propagated - the differences that convey an actual advantage are rare, but they are the only ones seen in retrospect (for example, in the fossil record).

Tom

 

Think it can be demonstrated that a singular mutational difference that occurs in generation one must be sufficiently advantageous and/or sufficiently innocuous to carry forward into subsequent generations...

 

Which is why Terriers survive in double figures whilst Leader is no more than a memory! (Does the NRM archive count as a fossil record for our purposes?)

Of the evolutionary record, I'd just note that the way 'new' fossilised species regularly turn up, we simply have to acknowledge just how incomplete our knowledge is.

... which goes some considerable way to explaining why I'm a bit mystified about the rationale behind the Churchward 'County' project ....

Bring back the trilobites!

 

The GWR locomotive can be made as half a County and half a City of Truro that went 100 mph on a sunny day.
Compound of course.
Distance between outside high pressure and indside low will not be much bigger than the Truro distance and cirka half the swaying County ditto.
Will only look od directly in front and can cash two times as many film jobs.

 

Half of something, half of something else, and of course all something it never was. I was currently unaware of the huge gap in the film market for GWR 4-4-0s, let alone 2...

 

The whole shebang seems predicated on what's the best fit for a particular niche slot. A role which might be filled here (say) by a mammal adapted to best exploit circumstances could as easily be filled on a remote island by a bird, reptile or even a crab species.

Another factor is the stability which goes with being an isolated community, where competition from invasive species is minimal. On Mauritius, the flightless dodo thrived until Europeans turned up ..... on the Isle of Man, much the same applies to the greater and lesser Beyer Peacock 2-4-0t!

 

One might also note the phenomenom known as Island dwarfing...

 

Bob only knows what gauge was originally earmarked for the line on the Azores then!

 

Ah, that would explain New Zealand ...

Tom

 

Colloquially known as "small chufferitis".

 

Earlier post 153. I have been asking around. There is an article on the Selkirk tests in the U.S. Magazine "Central Headlight" Vol XIII, no. 4 fourth quarter 1983. There is a patent : US no 2226052. I could not access it through the US Patent Office
website, Google Patent search supplied the detailed patent. Imho bad tests, changing two items at the same time, result longer chimney and chimney to orifice diameter ratios representing expelled product to steam, earlier chimneys too small.
They preferred round orifices with cross-bars due to the incomparable test results of other orifices.
Kind regards
Jos

 

Wasn't "Trilobite" an early broad gauge single? Cue the next GWS new-build project... ;-)

 

Trilobite would be a good name for a GWR loco: a successful initial design that then continued without change for the next 270 million years until wiped out by rapid, mass extinction to leave just a few old fossils to show what once was ...

Tom

 

there is no "Tribolite" in the list of" british steam loco names " so I doubt if there was one

 

Well there jolly well ought to be .... "Ammonite" too .... in fact, we've an entire newbuild theme to drive Starkey to despair ..... we could go from single vanished species all the way up to global extinction events.

Aren't I a little ray of sunshine?

 

It could be worse: unsuccessful initial design, then rebuilt every decade or so until kind of successful for another decade, then wiped out by rapid mass extinction. Let's call it...."Southernobite".

 

For the few that are interested, I have prepared a revised text on the calculation of multiple front-ends:
https://www.researchgate.net/public...front-ends_with_more_than_one_exhaust_orifice
It contains the inclusion of the Buckingham similarity explanation and has better diffuser test data.
Since my 80th birthday is nearing, this is my last contribution to the subject.
You are invited to falsify the approach, so far I have only received opinions on my earlier texts, not a shred of evidence for any improvements.
Kind regards
Jos

 

Thank-you Jos.
Will print off and stick in the back of your book.
Many Happy Returns...

 

Great stuff, Jos, and best wishes for your 80th. Nick

 

Jos seems have been a classic "voice crying in the wilderness". Some new technology is being incorporated in some restored and new-build locos, but few of them are getting improved draughting (or, come to that, any of the other Chapelon/Porta/Wardale improvements). Maybe one day?