help finding out how many wagons – Train Fever

help finding out how many wagons

Bartalos — Sat, 06 Sep 2014 11:32:31 +0000

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 )

Reply To: help finding out how many wagons

Mansen — Sat, 06 Sep 2014 12:47:06 +0000

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°

Reply To: help finding out how many wagons

Berry — Sat, 06 Sep 2014 13:03:50 +0000

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.

Reply To: help finding out how many wagons

Bartalos — Sat, 13 Sep 2014 10:27:41 +0000

any more simpler suggestions ? 🙂

Reply To: help finding out how many wagons

grimdanfango — Sat, 13 Sep 2014 12:07:26 +0000

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.

Reply To: help finding out how many wagons

mackintosh — Sat, 13 Sep 2014 14:57:23 +0000

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.

Reply To: help finding out how many wagons

Stonelouse — Sat, 13 Sep 2014 15:38:50 +0000

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.

Reply To: help finding out how many wagons

matsv201 — Sat, 13 Sep 2014 15:51:44 +0000

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

Reply To: help finding out how many wagons

matsv201 — Sat, 13 Sep 2014 18:52:37 +0000

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

Reply To: help finding out how many wagons

matsv201 — Sat, 13 Sep 2014 20:36:13 +0000

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=image

https://docs.google.com/spreadsheets/d/1yXOxTbFK7MijvjTyrSshSZBB0H574ThBh_rzKwZTf6U/pubchart?oid=877092420&format=image

https://docs.google.com/spreadsheets/d/1yXOxTbFK7MijvjTyrSshSZBB0H574ThBh_rzKwZTf6U/pubchart?oid=322411290&format=image

about this way