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Hello,
I am struggling to find out how many wagons can a train pull without losing much speed and i dont want to figure it out with try/error method.
can you please help me how to calculate it ? (suppose using tons /tractive force )
From the Steam forums (Assumption – not a tested theory iirc. Also keep in mind that wagons have a hard speed limit that the train won’t exceed)
Robbedem – some basic (simplified) formulas:
m = mass (ton)
a = acceleration (m/s²)
v = speed (m/s)
T = tractive effort (kN)
P = power (kW)
s = slope (°)
a = MIN [ T/m – g sin s ; 2 ( P/m – g v sin s)² / ( v (2P/m – g v sins s)) ]
vmax = P / m g sin s (provided that T/m > g sin s)
I don’t know the maximum slope in the game, but I guess it’s around 3,5°
It’d be a lot easier if a train would just simply state how much weight it can pull. That way you can easily calculate how many wagons you can attach.
I guess for the train geeks among us it’s nice to see how much power and tractive effort a train has, but for the game it isn’t very neccesairy or useful.
There’s no point saying how much weight a train can pull, because it can pull many different weights at different max speeds, accelerations, etc…
What would be useful is if, as you added wagons to an engine, it would give you feedback on what the current maximum speed and acceleration will be, on flat, moderate, and heavy uphill inclines. Even that I’m sure would need to be an approximation, but it would be good to get a general idea of how a train will perform at a glance.
Why would it be an approximation? The game knows exactly what those parameters are for every train and cargo combination. There is no guesswork involved here. Sure, presenting all that info would be overwhelming, but it could be configured to just show some basic indications, such as with this loco and this consist the train will average this and that on such and such grade/terrain.
it would be intersting to know what the gradient actually are in this game. maybe one of the devs who reads this can shed some light onto it?
if we presume that the height contours are spaced in a logical manner of say 5 or 10 m of height, we might roughly calculate the gradient according to phytagoras from the building costs of track.
just the track costs 50 moneys per metre, with the steepest incline it costs 6800 moneys to go straight from one contour line to the next, which equates to 136 metres. according to phytagoras that makes either 2,1 or 4,2 degree depending on whether the height lines are at 5 ot 10 metre intervals. that again equates to an inclination of either about 3,6 or about 7,4 percent for the steeper gradient. from the looks of it, i would think it is the steeper one.
its abvious however, that even though tractive effort is considered by train fever, it seems not to be calculated 1:1 to real physics. even a strong modern electric is not able to pull too many wagons up a gradient of 3,6 percent, let alone one of 7,4.
It would be nice with a simple graph for every loco. Like acceleration with, say 10, 20 , 50 and 100 ton behind (different colors) or/and maybe a graph with speed up different slopes.
Well, it probably be quite easy to do it in excell and put it in the forum
A idé to make this better is to put a link in the game to a specification side where all the data and graphs are, in that way you don´t need to calculate it your self, just read it in the graph… well, i try t make a example.
By the way, railroad inclination is usually measured in procent, not in degree. 3.5% is a usual inclination of the LGV track, but most normal track is around 1.5%, some super heavy freight corridors is only 1% and in some places normal track have a inclination of around 2-2,5% for example in the alps, there for they Swiz engines having very high pullingpower
Test
https://docs.google.com/spreadsheets/d/1yXOxTbFK7MijvjTyrSshSZBB0H574ThBh_rzKwZTf6U/pubchart?oid=1216125420&format=image
https://docs.google.com/spreadsheets/d/1yXOxTbFK7MijvjTyrSshSZBB0H574ThBh_rzKwZTf6U/pubchart?oid=1952022389&format=image
https://docs.google.com/spreadsheets/d/1yXOxTbFK7MijvjTyrSshSZBB0H574ThBh_rzKwZTf6U/pubchart?oid=530673885&format=imageabout this way
Yes it would be an approximation because the game doesn’t know in which route you will put the train and the slope of the track. You can also change the track with time or even the slope with terraforming. Its an approximation.
I quote the Interactive Guide if I may:
You don’t need to worry about the train being stuck in the track as a result of adding too much cargo. The train will always have a minimum speed of 1 Km/h.
As the calculation of the maximum amount of wagons a train can pull depends on the weight of each wagon, the state of each wagon (loaded or empty), the gradient of the tracks in the route and the tractive effort and power of each locomotive, simple observe your train along its route. If its too slow consider changing to a more powerful one or adding more than one locomotive.
Remember in real life they don’t know that information either. They don’t buy a train knowing exactly the route it will be taking as a train is used for 60 years in different tasks. They don’t know exactly the slope of each centimeter of the track the train will run.
Sometimes they don’t even know the space available in the stations the train will use. 🙂 http://www.bbc.com/news/world-europe-27497727
Are you being purposefully obtuse? The game knows exactly how many lines there are at each and every point in time. It should have no problems telling you whatever it is that we want to know about potential line speeds given consist composition whenever it is queried. It’s only a matter of deciding on what kind of information to present to the user so that it doesn’t become too cluttered and unwieldy.
To put it in the simplest of terms: You buy a loco, you hover over the line selection, out pops a window that shows you what the min/max/average speed of that loco is on this line (obviously not accounting for traffic). There. Done.
Please don’t use “real life” as an excuse for anything in this game. It makes my teeth hurt. This game is about as far from “real life” as Voyager is from Earth.
Just play a game through and test it. They can’t put what the “max wagons it can pull” are because everyone has different needs for different lines. Try it yourself and decide. Then look at the power of the next train in comparison and the weight, and use that as a rough guide.
The game shouldn’t be about super hardcore min-maxing and if you want to do that do the math yourself.
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