[rdamurphy]

I'm going to spend some time this weekend improving the steam locomotive particle generation, and try to make it look a little more like MSTS.

Any input on what it should look like and how it should work is greatly appreciated!

For smoke, generated by the fire in the firebox, we're looking at fire mass, fire temperature, and air flow, changing the color and mass of the exhaust.

For steam, we're looking at how much is generated, how much is being used, and how much is being blown uselessly out of the stack.

Do these mix completely in the smoke box, or are they emitted separately? How does the change affect the color? If there's a lot of steam, does it change the color of the smoke?

Any insight is helpful!

Robert

[captain_bazza]

http://uk.answers.ya...20045120AAGEkcl

This should explain what happens.

Cheers Bazza

[CrisGer]

As I recall and others can correct me, colour changes when the steam is being effectively applied or not. Dark Steam or smoke comes from poor combustion of the coal (or oil) and the lighter smoke is the better or standard. So glad work is underway. I will attach my smoke ACE from MSTS here which is as far as i can tell one of the most realistic ones available for MSTS.and i added some volume to it.

Sample on LPS MSTS FX 9600 Vid card, XP SP3 System

http://imageshack.us/a/img153/6985/lpscrossingview.jpg

Attached File(s)

•  CUSTOM SMOKE MAIN ACE.zip (984.97K)
  Number of downloads: 1055

[jared2982]

With the particle generation will it be possible to simulate the lack or almost lack of smoke when an engine has been at idle for a while?

[CrisGer]

OK got the reply back from my friend in the UK who is an engine driver here is his initial comment: re black smoke:

Quote

Okay ref to smoke Black denotes a bad burning fire ,really down to the fireman ,,,what should be seen out of the chimney is white like steam ,,one cant blame the driver for black smoke ,,though saying that he is in charge on the footplate ,so should see his fireman does his job correctly as with a novice fireman whacking to much in the box,, black coal on a already black fire ,.

i asked if he would be willing to help advise us here on the OR devel ..he has tried to install OR but it wont run for him yet, i will see what is up, he is very familar with MSTS as he tests many routes and engines for people in the UK community...so he may be able to help us with this.

[Genma Saotome]

A well fired steam locomotive running on an ordinary summer day will have exhaust w/ almost no opacity (e.g., smoke)... it's almost all just water vapor after all and it dissipates before condensing very much. Drop the temperature and the steam will begin to condense (opacity) to near white before it dissipates. Change the firing conditions and a whole lot more dark unburned particulate matter joins the water vapor. Perhaps that could be tied to the fire temperature: more particulate when firebox temps drop. And so to my thinking the questions become (1) should the activity file include outdoor ambient temperature to determine the extent of condensation -- the bulk of the exhaust? and (2) can the software control the color of the exhaust using a ratio of white smoke to black smoke -- the combined effects of ambient temperature and firebox temperature such that?

Also, the fireman may occasionally toss a handful of sand into the firebox, which gets sucked thru the tubes and scours off the carbon. Huge black smoke. You see this at run-by's all of the time. Might that be done with a simple n% chance checked whenever the firebox door is opened. 2%?

[gpz]

I would like to take the chance again to remind the developers that OpenRails currently doesn't have its own smokemain.ace file, it relies on MSTS provided one. I think this is the only remaining issue that prevents the steam locomotives to work with OpenRails out of the box, without MSTS installed. It would be good to include one such file (and a dieselsmoke one) into distribution, e.g. in content folder.

[CrisGer]

Good description Dave. Another factor tho is that if the weather is cooler the steam exhaust will condense more ..ie the white smoke, so that more white smoke will be generated depending on weather conditions so i think some smoke will be good to have no matter how the engine is operating or set. And ys i have seen that sand in the firebox trick mentioned several times in research on this. Sort of like Salt in the fireplace.

[_o_OOOO_oo-Kanawha]

US steam locomotives had to work and were worked considerably harder than their European counterparts. And with mechanical stokers or oil firing, could consume lots more fuel per hour. Fuel efficiency and fuel cost were not an issue on roads which owned their own coal mines.

Also I believe they generally had higher exhaust pressures, meaning a much more forceful exhaust, emitting a real column of smoke and steam intermixed when pulling away under full thottle with the valve gear in full forwards. Not to mention the thunderous sound of these separate exhaust blasts.

I would also like to see that large column.

Check as many photos and videos of US steam locomotives in action to get the right idea. Realisation in the simulator is quite another matter if course.

Here is my search of Railpictures.net on N&W steam, it should include original late steam era colour photographs from the 50's with A, J and Y classes.
N&W steam collection

Youtube is your obvious friend for videos.

[CrisGer]

http://www.railpictures.net/images/d1/6/8/5/1685.1325811924.jpg