Train Acceleration
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Train acceleration
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This page tries to summarize the algorithm used for realistic train acceleration. What follows is a description of the formulas listed at the bottom of this page.

This is incline of the train as a whole (or the sum of the inclines of each car), where 60simi is the incline of a single car i.

Units used

velocity [v] = mph

power [P] = W

mass [m] = t


F = 22P / 10v [N]

n — number of cars

μ = 35 (eq. 1e-3 ?) — coefficient of friction

A = 120 — area (units?)

d = 20+3n — drag coefficient

q = Σ 60simi — incline term, summed over cars

si — slope, -1 (going down), 0, or 1

mi — mass of the car

Fr = 4(13m / 10 + 60n + μmv / 1000 + Adv2/10000 + q) [N]

a = (F - Fr) / (m * 4) [m s-2]