What is the purpose of the side panels on this loco?
Gary
Those are smoke lifters..Instead of the smoke coming back toward the cab those "elephant ears" lift the smoke up.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
BRAKIEThose are smoke lifters..Instead of the smoke coming back toward the cab those "elephant ears" lift the smoke up.
What they actually do is more fun than that.
One of the original places railroad folks tried to apply aerodynamics was to induce some kind of 'lift' to the exhaust plume to get it up and away from the boiler. Lots of fins, wings, skyline fairings and the like, and even some redirected ducting acting to produce higher pressure or flow behind the stack to 'blow the smoke up.' These all failed for reasons obvious to those looking at the actual physics of exhaust action, let alone actual aerodynamic flow.
Then we get into the latter-Thirties experimentation with low-back-pressure multiple-nozzle front ends. These often had the consequence of reducing the energy 'wasted' in too energetic an expulsion of entrained combustion gas, at the same time that higher speed exacerbated the vacuum effects along the boiler following the bow shock of the relatively flat front end of the locomotive.
The elephant ears were originally conceived as a means of channeling high pressure at the front first to the sides then upward 'to carry the smoke up'. What they actually did was generate vortex effect overcoming the vacuum pulling the exhaust down toward the cab front. Usual American versions were empirically sized, made of plate because it minimizes effect on forward visibility from the cab. The Germans, looking at this more scientifically, came up with the rakish Witte deflectors seen on much of the postwar fast power over there -- that's as close to the right approach as is really needed.
(In case you are wondering why UP put deflectors on the FEF-3s, but even after testing did not put them on the FAR smokier 4-8-8-4s, this explanation will give you a leg up on some of the reasons...)
Note that there was never an attempt to put American-style 'smoke deflectors' (probably the best 'term of art' for the things) on a PRR T1, which for an evil confluence of reasons was probably the poster child for bad vacuum effects. There are pictures on one of the Teains Magazine forum threads showing what a properly-designed set of Wittes would have looked like ... not too bad!
According to the book "How Steam Locomotives Really Work" (Published in England, includes TONS of math), they are pretty simple.
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They were not intended to do anything when the locomotive was moving. Instead, when the train was sitting still,and there was a cross-wind, the smoke would go down the side of the boiler and choke the crew in the cab. These "ears" changed the way that wind flowed, and the smoke would not go into the cab.
The book also said that is why they were not very common on North American locomotives. It seems our locomotives spent a lot more time moving and less time idling. The book said in North America they were used almost only on Passenger Train locomotives that sat still for some time in stations.
I have no idea how much of that is true.
-Kevin
Living the dream.
SeeYou190I have no idea how much of that is true
British equivalent of explaining how roller muffler bearings are better than plain or Alemited ones, or why synthetic blinker fluid works properly down to lower temperatures. Or why you need safety valves on the superheater of a locomotive with a front-end multiple throttle because it's a separately-fired pressure vessel with the throttle closed and the reverser centered if there is any priming in the elements. Bet they say elsewhere that compounds 'use their steam twice' too.
You'd have to be extraordinarily gullible, naive, and 'engineering challenged' to swallow that yivshish. It even fails the common-sense 'what does front-end smoke do in a crosswind' test.
Perhaps if you had one of those British engines with the Franco-Crosti economizer and put some kind of airfoil across the top of the boiler back at the exhaust duct it might work if the wind were exactly wrong and blowing constantly... but even then there would be better solutions.
OvermodYou'd have to be extraordinarily gullible, naive, and 'engineering challenged' to swallow that yivshish.
...but I know the VentiPorts on the front fenders of my 1956 Buick Roadmaster were fully functional.
Weren't they?
Cheers! Ed
There's a model of a Big Boy with smoke deflectors I am considering some day buying one...
It could be likened to a '69 Mustang Mach 1 Fastback, it has a hood scoop AND rear fender scoops (that would "in theory" cool the brakes, both are non functional! No I'm sure a few industrious fellas out there have made them "functional" bit stock they weren't!
Steve
If everything seems under control, you're not going fast enough!
SeeYou190 ... They were not intended to do anything when the locomotive was moving. Instead, when the train was sitting still,and there was a cross-wind, the smoke would go down the side of the boiler and choke the crew in the cab. These "ears" changed the way that wind flowed, and the smoke would not go into the cab...
...
They were not intended to do anything when the locomotive was moving. Instead, when the train was sitting still,and there was a cross-wind, the smoke would go down the side of the boiler and choke the crew in the cab. These "ears" changed the way that wind flowed, and the smoke would not go into the cab...
Wow. The author didn't know about how smoke lays down along the boiler and obscures vision on locomotives at speed in the right wind conditions...I guess. That problem led to the demise of Norfolk & Western's Class J #607.
http://www.railpictures.net/photo/40480/
The engineer reported later that the smoke obscured the signals, and that neither he nor his freshly killed fireman had seen a signal indicating they were to cross over ahead and to reduce speed.
So, was it a good thing the J had, or that it didn't have, smoke lifters? Or that it was moving with or without them in place?
SeeYou190 I have no idea how much of that is true. . -Kevin
Every word. Said differently.
OK, but the description in this book went far and beyond anything I have ever read about "elephant ears" anywhere else. Complete with diagrams, air flow arrows, explanation of pressure differentials, and stream flow, and so on.
If it is not true, it sure was a well argued point of view.
I never really put much thought into it. I always thought these ears were ugly. The STRATTON & GILLETTE will have none.
The NKP 4-6-4's were manufactured with and without them, and they look so much better without.
It is a preference, then, but several roads used them for apparently good effect if they left them in place. Funny, but I have come to like them on the ones that are heavily imaged across the net, such as the FEF and Niagara. Even the "greyound' UP Challengers had them.
SeeYou190OK, but the description in this book went far and beyond anything I have ever read about "elephant ears" anywhere else. Complete with diagrams, air flow arrows, explanation of pressure differentials, and stream flow, and so on.
From the nation that proved with math that a bumblebee couldn't fly.
See Angus Sinclair on the subject of clever little arrows in patent drawings that show how the steam flows. Problem is that sometimes the fact that steam can't read causes some issues.
One of the oldest 'Grant Swing' science techniques is to win arguments with plausible-sounding scientistic arguments. There are whole academic disciplines founded largely on this principle. You might recap some of that book's math argument here, in fair use/paraphrase, for more specific comment.
OvermodYou might recap some of that book's math argument here, in fair use/paraphrase, for more specific comment.
Sorry, I gave the book away a long time ago. Too much math, too few pictures. If I still had it I would have cited the auhor and publisher in my original post.
I loved all the comments the author made about North American steam. Each chapter was basically... here is why we do it, here is how it works, here is the right way to do it, here is what they did in North America, this is why our way is better. The four page commentary on how North American Railroads ruined the Mallet design was good for quite a few laughs.
Now I want the book back.
For the record I think this was Semmens and Goldfinch, from 2003 or 2004, with a roller-bearing eccentric-rod big end against a spoked driver dramatically on the cover.
As my old girlfriend said 'it had more bugs than a New York apartment with peanut butter smeared on the walls'. But you can get a copy from Amazon for just north of $15 shipped, if you must have one.
I had a 69 with hood and fender scoops! Actually, the fender scoops were designed to keep the people in the trunk from suffocating.... I know this to be a FACT...
Mike C.
BRAKIE Those are smoke lifters..Instead of the smoke coming back toward the cab those "elephant ears" lift the smoke up.
BigJim Ask anyone that operated an ALCO RS11 long hood forward!
Jim,I had photos of a consist of 4 N&W RS11 that was putting the smoke out..I really felt bad for that crew and fully understood why the N&W crews called them "junkers".
Well all I know is that I don't get any smoke in my eyes when I run my trains. Well, not from the trains anyway. This discussion was an interesting read.
Chip
Building the Rock Ridge Railroad with the slowest construction crew west of the Pecos.
These are correctly called (according to UP Drawings) "Wind Wings" they are for drafting the smoke away from the crew and over the locomotives. They were used on the 4-6-6-4's. They were even tried on the 3985 for a couple of trips. They didn't work too well way out there on the boiler, they also made it harder to see around them. Vision can be a problem on curves on a big articulated like that. They were tried on a UP 4-8-8-4, the 4015, which seemed to be the test bed locomotive for UP. It was converted to Oil for a time but was deemed a failure.
UP kept the Wind Wings on the FEF (Four Eight Four) series but with the exception of the 4-6-6-4 oil burners, mainly used in Passenger Service, they appeared in quantity no where else on the UP system.
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I believe all eight NKP 4-6-4's were manufactured without smoke lifters, and they were added to all eight in their later years.
Tom
Overmod From the nation that proved with math that a bumblebee couldn't fly.
Ah, but here's the rub: they did prove bumblebees can't flying based on the model for rigid wings. For instance, their wings do not generate enough lift when not moving for a bumblebee to glide. Clearly birds, butterflies, bats, and other flappy things can glide, but their wings are far more rigid and have a larger surface area to body mass ratio. The part left out is the conclusion that their model must not apply to bumblebees and they must be using some other method to fly.
Had they based their bumblebee calculations on the model being produced in the nascent helicopter developments, they'd have come to some very different conclusions.