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mlangsdorf / Cataclysm-DDA

Cataclysm - Dark Days Ahead. A fork/variant of Cataclysm Roguelike by Whales.
http://en.cataclysmdda.com/
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New Model of Vehicle Speed #29

Closed mlangsdorf closed 6 years ago

mlangsdorf commented 6 years ago

Engines have an RPM range between 1000 and 8000 1 RPM = 120pi() rads/s Engines have a transmission efficiency, usually around 0.7 Engines have a differential gear ratio of 3.5 Engines have multiple gear ratios 3, 2, 1.4, 1, 0.75, 0.5 ( or so ) - some engines (pedals) may have other ratios <- may simplify this into a single gear ratio Transmission power is ( engine power - alternator power ) transmission efficiency Wheel force is transmission power differential gear ratio / ( wheel radius rps ) Net Gear ratio is differential current gear ratio Speed is rps wheel radius / (differential gear ratio ) Force Rolling drag is some -constant speed Force Air drag is -bunch of constants speed^2

V = rps Rw / G Fw = Pt G / ( R rps ) Fd = Cr V + Ca * V ^2 max V is Fw == Fd

I want rps and velocity

rps = G V / Rw Fw = Pt G / ( Rw G V / Rw ) == Pt G / ( G V ) == Pt / V Fw = Pt / V Ca V^2 + Cr V - Fw = 0 Ca V^3 + Cr V^2 = Pt estimate V, then fine tune Engine RPM is 30 V G / Rw / pi()

For the test corvette, max V is about 78 m/s (174 mph) and can be achieved in 4th at 7.6 krpm, 5th at 5.7 krpm, 6th at 3.8 krpm.

mlangsdorf commented 6 years ago

For a range of engines, V can be approximated to cube root ( transmission power / Ca ) - Cr * Cdair