WOLFRAM

WOLFRAM SYSTEM MODELER

AirResistanceLongitudinal

Velocity dependent longitudinal air resistance

Wolfram Language

In[1]:=
SystemModel["PlanarMechanics.VehicleComponents.AirResistanceLongitudinal"]
Out[1]:=

Information

The vehicle's air drag, resolved in frame_a, is calculated as: 

fDrag = ( c_W *  area * rho * v_x^2 ) / 2

where: 

c_W           : air drag coefficient,
area          : cross area of vehicle,
rho           : density of the air,
v_x = vAir[1] : longitudinal component of air velocity, resolved in frame_a.

Just air drag in vehicle's longitudinal direction is calculated here, which can be specified for frame_a.phi = 0 by the parameter r. For example for r = {1, 0} the driving direction is in x-direction of frame_a and, thus, frame_a.fx = fDrag. The other forces and torque are disregarded.

Note

This model is limited to negative air velocity v_x only. For positive velocity, which can occur e.g. when driving rearwards, the air drag is set to zero.

Parameters (4)

c_W

Value:

Type: Real

Description: Drag coefficient
area

Value:

Type: Area (m²)

Description: Frontal cross area of vehicle
rho

Value: 1.18

Type: Density (kg/m³)

Description: Air density
r

Value: {1, 0}

Type: Length[2] (m)

Description: Driving direction of vehicle at angle frame_a.phi = 0

Connectors (1)

frame_a

Type: Frame_a

Description: Coordinate system (2-dim.) fixed to the component with one cut-force and cut-torque (blue icon)

Used in Examples (2)

TestAirDrag

PlanarMechanics.VehicleComponents.Examples

Test air drag model

SingleTrackWithEngine

PlanarMechanics.VehicleComponents.Examples

Single track model

Revisions

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