Download : CALCULATIONS FOR FNR GEAR BOX AND CVT COMBINATION
Gear Reduction Selection
Power Requirements against:
Fr: Wheel Resistance
FL : Air resistance
Fs: Gradient resistance
Fa: Acceleration resistance
Wheel Resistance= Rolling resistance + Slip Resistance + Road Resistance
Tr: Brake Torque
Assumption taken
Unmade road coefficient of friction fr= .16
mass of vehicle being=Mf
CALCULATIONS
Fr=fr*Mf*g*Cosαst where αst=30˚
Fr=0.16*200*9.81*Cos 30
Fr=280N
Total Load R=113kg(driver)+200kg (vehicle)
R=313*9.81=3070.50N
Static Resistance=µR
=0.65*3070.5=1995.84N
Vmax=60kmph
Wheel Radius r=221.875mm
= .221m
Air Resistance
FL:0.5ρCwAv2
Ρ=Air Density
Cw=Drag Coefficient
A=Area
V=velocity
FL =0.5*1.99*0.0315*(16.66)2
=0.52N
Gradient Resistance:
Fst=Mf*g *Sinαst
Putting the corresponding value
Fst=131.725N
Acceleration resistance:
Fa=m*a
=956N
Ftotal=2662.247
Power Required: Ftotal*v/(Nrpm*η)