[farrmp]

Just an observation from all the videos and all the Operating Steam Loco's I've seen --
THERE ARE A LOT OF STEAM LEAKS! Part of the attraction of the machines.
I think Steam Effects are a worthy addition to the Simulation, particularly in colder climates.
If they don't seem appropriate, then don't bother to put them in the .ENG file.

Paul

[copperpen]

steamer_ctn, on 03 March 2016 - 02:22 PM, said:

The speed is used as a surrogate means of simulating the amount of air provided to the fire, ie the slower the locomotive goes, the less air coming through the damper into the fire, the faster it goes the more air available.

The challenge with modelling the smoke colour, etc, is tying the colour change to a value that varies in OR in a way that produces the most realistic desired outcome.

So the trick is to develop an algorithm (or formula) based upon the values used by OR (the extended HUD gives a view of most of them).

Studying the extended HUD might give some suggestions about better variables to consider other then speed to tie the smoke colour to.

The MSTS method was to change the smoke colour when fuel was added to the fire. In order to do the same in OR there is a need to rethink the auto firing method currently in use. One way would be to use a lower boiler pressure, probably as a percentage of full pressure as a start trigger, and the ideal firemass plus a small percentage as the stop trigger for firing. Then the smoke colour could change just after the start of firing and gradually move back to white or clear over a defined time period.

Then we need to rethink the particle physics to give a similar effect to MSTS, specially at rest where the exhaust should not just hover above and around the stack, but move clear using the fire draft to generate it.

[steamer_ctn]

copperpen, on 11 March 2016 - 02:37 PM, said:

The MSTS method was to change the smoke colour when fuel was added to the fire. In order to do the same in OR there is a need to rethink the auto firing method currently in use. One way would be to use a lower boiler pressure, probably as a percentage of full pressure as a start trigger, and the ideal firemass plus a small percentage as the stop trigger for firing. Then the smoke colour could change just after the start of firing and gradually move back to white or clear over a defined time period.

This raises two questions for me?

Firstly my understanding of the particle drawer is that it can show a range of colors from white to black. Thus it would only be possible to have either white or black smoke. It maybe possible to have "no smoke" (ie turn the smoke output off), which could possibly simulate the clear smoke situation. Is this the suggestion, or only have a black or white color range?

Secondly to control the smoke color, is it suggested that whenever the fireman adds fuel, ie between the start and stop trigger points suggested, the smoke will be black, and outside of these points the smoke will be white? What reference parameter would be used to move the smoke from black to white between these two trigger points?

Thanks

[copperpen]

steamer_ctn, on 12 March 2016 - 11:24 PM, said:

This raises two questions for me?

Firstly my understanding of the particle drawer is that it can show a range of colors from white to black. Thus it would only be possible to have either white or black smoke. It maybe possible to have "no smoke" (ie turn the smoke output off), which could possibly simulate the clear smoke situation. Is this the suggestion, or only have a black or white color range?

Secondly to control the smoke color, is it suggested that whenever the fireman adds fuel, ie between the start and stop trigger points suggested, the smoke will be black, and outside of these points the smoke will be white? What reference parameter would be used to move the smoke from black to white between these two trigger points?

Thanks

From observation the particle drawer is able to display any monochrome colour between black and white, many shades of grey that are currently controlled by the locomotive controller positions when moving. The initial stack velocity is sadly lacking in this implementation of the particle drawer, but that is a separate issue.

To control the smoke colour it could be possible to use the initial trigger to start the colour change, and the second trigger point plus a percentage of the pressure reduction to reverse the colour change.

The first thing to do though would be change the firing method to little and often instead of the current "on all the time". To cater for the less than full pressure " hot or cold" starts that we have It might also be good to put a time limit on the firing duration, suggesting 1 minute as a starting point.

[atsf3751]

Another thing to point out is with most American steam locomotives they are big enough to have stokers to help with the firing but the locomotive still needs to be hand fired as well to pick up hot or cold spots in the fire box. Also oil firing is completely different all together VS Coal. When it comes to oil fires the smoke is usually only back if there is bad oil or the locomotive is getting its flues sanded. Just a few other pieces to think of in this very complicated puzzle we are all trying to put together!

Brandon

[copperpen]

Both good points, but lets get hand firing right first, stoker and oil can follow on. Better to chew one bit at a time than try to swallow the whole cake in one go.

[atsf3751]

Yes I agree.

[longiron]

Here's a good youtube video that really goes into firing a steam locomotive and the resulting color of the smoke: https://www.youtube....h?v=74JaLw3u3-c

Remember, firing will depend on the load (steam usage) so running flat and level will only have minor color variations, while climbing a 2% grade will have major color variations as more coal is added to the firebox at a time.

chris

[Traindude]

copperpen, on 11 March 2016 - 07:10 AM, said:

I have seen some steam locomotives that have an exhaust for a pump of some kind, probably air, piped to a location behind the stack.

That is true. Sometimes some locomotives exhaust their air pumps through a separate pipe mounted close to the main stack. This is also a common arrangement on locomotives with booster engines (example NYC J3a nonstreamlined Hudson). But I think about 85% of auxiliaries are exhausted into the smokebox, feedwater heater or cylinder saddle.

[QJ-6811]

steamer_ctn, on 20 February 2016 - 07:57 PM, said:

Posted 20 February 2016 - 08:57 PM

Based upon the the principle that steam effects should be included for those elements that occur on the majority of locomotives (eg steam whistle), and that they should be clearly visible (eg steam cylinders), otherwise they don't warrant the effort to try and code them, the following effects are now supported:
•Steam cylinders
•Stack
•Compressor
•Generator
•Safety valves
•Whistle
•Injectors
NB: The drain pipe has been disabled in this version of the patch.

An idea for a very high steam effect?
Steam locomotives have "boiler blow off". I used the "V Wipers" function for the blow out sounds.
An extra steam effect of this function will be very welcome.
(Certainly for the steam locomotives with sideways outlet.)

just an idea ...........

[captain_bazza]

Sounds like interesting progress in the sFX department. It might prompt my interest in modeling.

Cheers n thanks for all the hard work being done,
Bazza.

[Traindude]

Okay:

An observation I have made in real life is that when auxiliares such as air pumps/compressors, stoker engines and booster engines exhaust into the locomotive's main exhaust nozzle or the exhaust passages of the main cylinder saddle, the operation of these devices has an influence of the velocity of the main stack emmisions. This is most obvious when the engine is under steam at a standstill. The increase in velocity is not as great as when the main cylinders are exhausting (the throttle/regulator is open) but the velocity is till modulated slightly by the operation of the pumps/stoker/booster. However, the density of the stack emmisions are unaffected. I believe that is due to the fact that the draft generated by the auxiliaries is not enough to affect the smoke density. As mentioned earlier, this applies only to piston-driven auxiliaries. Turbine-driven auxiliaries, such as the centrifugal cold water pump on a Worthington Feedwater heater system or a turbo-generator, must ehaust directly into the atmosphere (although the centrifugal pump used with the Coffin feedwater heater exhausts to a port inside the smokebox about two feet below the main stack).

However, if the compressors exhaust directly into the atmosphere this is what you see (this engine has its compressor exhaust pipe clamped to the inside of the main stack). And if the engine has a feedwater heater used in conjunction with reciprocating pumps, the water pump and air compressor exhaust into the feedwater heater to heat the water even when the main cylinders are not working.

[atsf3751]

not always the case because it depends on the locomotive and how its set up

[atsf3751]

Another thing I thought of is will it eventually be possible to do a blow down of the boiler while running? Also I know the Cylinder cocks can be reacted with the C Button now but it would be nice if they could also be simulated by how much pressure are in the cylinder heads themselves instead of just streaming out like they do now.

Brandon

[longiron]

Thought this was an interesting site on graphically simulating particle physics. http://nullprogram.c...ebgl-particles/