Who's Good At Math?

[socalwb909]

-Who is good at math? Who knows about Horsepower Per Ton (HPT), Tractive Effort (TE)? I've been making an excel document to tell me some basic information about the locomotive power I would need for my train, or how the railroad figures it all out in the real world and then apply that info to TANE. Here's what I have so far:



-What I'm trying to figure out is, how many locomotives (horsepower) do I need for my train. I want to meet the minimum requirements. Here's my example:

-My train has a trailing tonnage of 4,000 tons. My max grade percent is 1.6%^. The minimum HPT to meet or exceed is 2.0. How many locomotives or horsepower do I need to meet the minimum HPT? And to get a little more technical, how much TE do I need for climbing the 1.6%^ grade? (So if I was to stop my train it wouldn't pull me back down the hill and I'd be able to get my train moving again if I had to stop) And how much TE do I need to safely go down a 2.2%v grade (so I have enough braking force to stop the train on that grade)?

-I believe the formulas are... To get TE is: TE = (HP x 375 / Speed). To get your HPT is: (HPT = # of locos x total HP / trailing tonnage) (not sure if to add locomotive weight or not). Formula for speed is: speed = HPT x 12 / % of grade. (Correct me if I'm wrong in any of those formulas)

-If anyone could help me on my excel document I'd greatly appreciate it. If I get all the info I need I could post this excel calculator document up at my site if anyone was interested in prototypical consist setups inTrainz.

-Joe

 

[JCitron]

Hi Joe,

Justin Cornell has a spreadsheet that does just this.

See this thread here:

http://forums.auran.com/trainz/show...adsheet-Engine-HP-rating&highlight=horsepower

His link is at the bottom.

Hopefully this will save you the angst of doing math.

 

[cascaderailroad]

The heck with all the math ... What numerals in an engine spec config file give you ludicrouus speed, rediculous adhesion and traction, and hyper horsepower, and maximum braking?

 

[64Warhorse]

Joe, you might find this site useful, particularly the link about horsepower vs tractive effort: https://web.archive.org/web/20090415172558/http://www.alkrug.vcn.com/rrfacts/rrfacts.htm

 

[cressjl]

The heck with all the math ... What numerals in an engine spec config file give you ludicrouus speed, rediculous adhesion and traction, and hyper horsepower, and maximum braking?

This brings back memories of the hack I used to enter into Doom (back in the day) to gain superhuman powers. I suppose Auran had the Hotrod F7A, still listed as <KUID2:999999:100100:1> (for real?), which had souped-up specs.

 

[Christopher824]

If you can prove that the formula is correct, I can make a downloadable executable in .NET for it and would be willing to serve it on my servers.

-I believe the formulas are... To get TE is: TE = (HP x 375 / Speed). To get your HPT is: (HPT = # of locos x total HP / trailing tonnage) (not sure if to add locomotive weight or not). Formula for speed is: speed = HPT x 12 / % of grade. (Correct me if I'm wrong in any of those formulas)

 

[phimat]

Back with Tr2004 (I think), I set a loco running a circuit for over twelve hours. Managed to get the speed up to 9000+mph. It drove children wild, sitting in the cab and whizzing about!

 

[allainp]

You can also find a Railroad Forces Calculator and many interesting facts on Al Krug's Page.

 

[socalwb909]

Joe, you might find this site useful, particularly the link about horsepower vs tractive effort: https://web.archive.org/web/20090415172558/http://www.alkrug.vcn.com/rrfacts/rrfacts.htm

-Thanks for this. It has really helped develop my calculator. Still working on it, till I'm happy.
-Thanks everyone for your comments. Much appreciated.

-Joe