DragForce_Train
Procedure DragForce_train returns the drag force for a conventional passenger train
Inputs
Fluid$ - the name of any fluid in the EES data base. Fluid$ may be a string constant or a string variable.
T - temperature in the defined unit system [F,C,R,K]
P - pressure in the defined unit system [Pa,kPa,bar,MPa,psia,atm]
v - free stream fluid velocity in [m/s, ft/min]
NC - number of cars including the lead car
A - the frontal area of the vehicle in [m^2] or [ft^2]
Outputs
F_d - drag force per unit length [N or lbf]
C_d - drag coefficient {optional}
Re - Reynolds number {optional} {value is not needed for the calulation and the result returned is an estimate}
This procedure calls function DragCoefficient_SemiTruck to obtain the drag coefficient.
Example:
$UnitSystem SI C kPa
Fluid$='Air'
T=25 [C]
P=Po#
v=10 [m/s]
NC=15
A=9 [m^2]
CALL DragForce_Train(Fluid$,T,P,v,A:F_d,C_d,{Re})
{Solution:
C_d=2.77
F_d=1476 [N]
}