Steam engine operation guide

JimDep

Well-known member
I'm having trouble keeping up the steam on a new engine I'm trying out. While doing a familiar run between two locations, the coal drops faster than what I'm used to on this engine.
It won't reload on coal when stopping on a coal uploader, even though the right click details said it did. visually, it doesn't show the coal getting low to begin with. Inside the cab, the HUD shows no increase on coal percentage after doing a coal load. The icon inside the tender shows it being a wood burner, visually, it's coal in the tender, but stopping at a wood shed to do an upload doesn't work either.

Before I get too specific, I want to refresh my understanding of how this is all supposed to work , so I'm looking for a Trainz steamer operation guide that applies to T:ANE. Doing the usual searches isn't coming up with anything.
Can someone point out a link for me please ?
Thanks
 
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It sounds to me Jim as if there's something either with the engine spec or the config file that's not set up properly.
 
It sounds to me Jim as if there's something either with the engine spec or the config file that's not set up properly.
Thanks KG, that could be it.
Here's a pic to show what's going on. The 86 PSI won't last long, regardless of what I do to keep the pressure up. I never knew what the coal level slider is for on the right of the HUD. It's never made any difference when I use it...that I know of. I know the water level is too high...normally I try to keep it around 65%
steam-pressure-test.jpg
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If the config file is setup for the correct fuel, - in this case wood, - and nothing is happening when you use the coal/fuel slider to add more wood to the fire, - the usual cause I've found is that the fuel feed rate in the engine spec is set too low. If you have another engine that you know is working correctly try swapping its engine spec for the one in your PRR 4-4-0. If things suddenly improve you'll know it's the engine spec that's the problem.
 
Sorry Jim. I mainly run old British tank engines so please excuse my mistake. Yes it should be the tender that's set up for water and fuel loads, but the engine spec for the loco controls things like the injectors and the coal shovel load (log size?).
 
Thanks again, KG.....shouldn't it be the tender that's the issue instead of the loco ?
Jim as Ann said the tender only specifies the fuel and water queues and indicates the products held in those special queues. A product asset does specify a mass density and for the the fuel and water held in the tender this is used to determine the total weight of the tender. In past versions of Trainz however, based on testing, this mass density of the fuel product is ignored by the game engine and a hard coded value of 0.86 kg/ltr is used instead for transferring any fuel from the tender to the firebox regardless of what is specified in the product config. 0.86 kg/ltr is the mass density of the coal product used by Auran/N3V for steam loco fuel. I don't know if this has been corrected in newer versions as I haven't checked for it in a number of years.

There are 2 required properties of fuel that are not specified in the fuel product asset. They are specified with the following tags in the espec:
1)fuel-energy
2)fuel-specific-heat-capacity
These specify the heat energy released by the fuel as it is burned and the energy required to heat it to a specific temperature in the firebox.

The espec also sets the minimum and maximum temperature of the fire. A characteristic that is dependent on the fuel burned and are specified with the following tags in the espec:
1)min-fire-temperature
2)max-fire-temperature

The espec also sets the size of the grate indirectly by specifying the amount of fuel it can hold at optimum and maximum capacity, this is also dependant on type of fuel used, with the following tags:
1)ideal-coal-mass
2)max-coal-mass

So an espec developed for a coal burning firebox would have different fuel energy, temperature and capacity values from a wood burning or an oil burning firebox. The fuel characteristics for these fuels are considerably different from each other. Actually different grades of coal should have slightly different values in the espec as would different fuel oils and different species of wood.

One might think that you could specify a different fuel to be carried in the tender and it would affect the locos performance but it doesn't. The properties that affect loco performance are specified in the espec and not in the config of the fuel product asset. If you change the fuel used you have to make several changes in the espec if you want to simulate realistic performance.

The amount of fuel added to the grate per shovel is also specified in the espec with the shovel-coal-mass tag. In past versions (IIRC TS 12 was the last version I checked) as noted the games always uses 0.86 kg/ltr as the value to convert the mass per shovel to liters of fuel removed from the tender. The actual value specified in the fuel product's config is not used. I'll also mention that truncated integer values are used by the game in the calculations involving the product queues. A bit picky I know but it could have been handled better at least IMO. With a large amount of product transferred at one time, the truncation to an integer value is a reasonable procedure but when hundreds of small values, as per shovel, are transfered the conversion error gets magnified and it will be more than just a few kgs out of a tender's total capacity. Yea, I know picky.

Bob Pearson

PS. There are a number of other tags in the espec that affect how the fuel is burned plus a number of efficiency tags that affect the total amount of useful energy converted into work to move the loco. Maximum steam flow tag and cylinder sizes determine steam consumption per stroke. But the animdist tag in the steam driver bogey actually determines steam consumption per unit time - actually distance traveled per rev in conjunction with the loco's speed. So while the espec is the major part of this it isn't the only one involved in simulating realistic performance.

We don't have much if any control on the actual draft produce thru the boiler either - that should be addressed at some point by N3V. We've been waiting for a dozen years or so for this "new feature" to appear - some of us less patiently than others I suspect.
 
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I'm having trouble keeping up the steam on a new engine I'm trying out. While doing a familiar run between two locations, the coal drops faster than what I'm used to on this engine.
It won't reload on coal when stopping on a coal uploader, even though the right click details said it did. visually, it doesn't show the coal getting low to begin with. Inside the cab, the HUD shows no increase on coal percentage after doing a coal load. The icon inside the tender shows it being a wood burner, visually, it's coal in the tender, but stopping at a wood shed to do an upload doesn't work either.

Before I get too specific, I want to refresh my understanding of how this is all supposed to work , so I'm looking for a Trainz steamer operation guide that applies to T:ANE. Doing the usual searches isn't coming up with anything.
Can someone point out a link for me please ?
Thanks
Some tender loads would use a texture swap using a texture from the fuel products asset. You'd have to check the tender's config to see exactly what fuel product(s) is specified for the "load-coal" queue. Loading the tender regardless of whether it's wood, coal or oil has no effect on the % of fuel shown in the HUD. The % indicates the amount of unburnt fuel currently on the grate as a percent of the fuel's "optimum" mass value. You can hit the spacebar to load 1 shovel of fuel onto the grate at a time. I'm not sure what exactly the slider on the HUD does I don't use it. I manually add fuel with the spacebar. For oil burners of course the % fuel on the grate has no realistic meaning since it is atomized and sprayed into the firebox by the burner in a continuous fashion. But we can and do use work arounds until this "new feature" to simulate oil burners is also added sometime soon - maybe.

A for the tender it should reload fuel at any industry that can load the kind of fuel that is specified in the tender's config set up for the fuel queue. Most tenders now have a custom script that prevents them from unloading fuel at similar industries.

Fuel on the grate in the firebox is indicated in the HUD. Fuel remaining in the tender's queue is displayed when you view the tender details or if using the idiot bars floating in the air above it.

Bob Pearson
 
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so, older models, like that (its a Ben Neal 2006 model if i remember correctly) will not work properly in realistic mode, actually, all steam locos go nuts in that mode, ive gotten brand new Trainz Forge steamers up to 300 on a 40 percent up hill grade. The other thing is, the tender fuel and the loco fuel amounts sometimes dont work with each other well ive found. It is fairly hard to get some steam locos running in that mode.
 
Well if the older loco is still using a pre- TS09 kind steam-engine espec then it probably won't run as it was originally designed to since the game has to estimate various other parameters to make it run under the new steam physics system. That doesn't mean it will go nuts by any means but some cases are much worse than others. So I recommend you don't use the older especs - develop a new one for the loco in question. I'll add the same warning and recommendation if it's using a pre TS09 engine-sound asset.

I do though have to disagree with this part of your comment: "... will not work properly in realistic mode, actually, all steam locos go nuts in that mode ...". In my experience many espec give a satisfactory performance based on my own testing of them in the game.

Nearly all steam-engine especs are developed by Trainz users and content creators. N3V employees account for only a scant few of those produced. The competence varies - considerably. It's not a simple or easy task - it is in fact a very complicated task which is hindered because we have no standard way to test steam locos in the game. Every content creator comes up with his own method which can vary from: well it worked with other locos let's use it; to a complete testing regime measuring and recording loco performance vs time under runtime conditions in the game - something like N3V should have provided but so far they have not. I'll be the first to tell you there are problems with the current steam physics but to say they all go nuts is not the case IMO. Fuel and water consumption are a function of many things - espec setup, drive wheel bogey animdist and not least the user's ability to handle the steam loco in an efficient and realistic manner.

Is 300 mph realistic? - not at all (nor is 300 kph). But I've never got one using my own especs to more than about 150mph in a light condition. But that's not realistic either. No engineman would handle a loco in that manner to begin with and driving a lite loco they probably could be run off the rails if not handled properly in real life. I'll tell you right now most of my testing indicates that the steam physics in Trainz, using the current especs developed using the actual dimensions of the loco's machinery, will develop too much power when going in the forward direction. So IMO they have to be "adjusted" in some manner. If you use Bill's Fock's espec generating spreadsheet you'll get modified steam cylinder sizes to compensate for this. I don't use Bill's spreadsheet for a few reasons but it will get you drivable especs you can at least tweek. I do something similar though when developing my own but I modify not only the cylinders size but the whole steam generating part of the espec to compensate so the fuel consumption has some chance to match prototype numbers and evaporation doesn't far outpace steam consumption.

Bob Pearson
 
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Thanks for all the info, Bob. I even gave the grate a good shake...that didn't do anything either :) It should have helped bring the fire up a little, anyway.
Thank you KG and KCwright

I HAVE been running this in realistic mode. It didn't occur to me that this might be part of the problem. Also, I'm glad I'm not the only one who doesn't know what the HUD coal level slider is supposed
to do. I've never seen it make any difference.

Reading journals from back in the late 1800's, I know exactly how far the engineer would go before making a water stop, and reloading the wood in the tender for the specific route I'm working on. The engines they used , Utica & Black River RR, were so UN standardized at that time, it's hard to know what the specs were, but it would be nice to set the wood / water levels for the closest steamer I can find to match the distances they went before having to "wood up". I'm not sure if that's possible.......but if it is.......any suggestions for a simple brain like mine to comprehend ? :) Thanks .
 
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