WOLFRAM SYSTEMMODELER

GasForce2

Rough approximation of gas force in a combustion engine's cylinder

Wolfram Language

In[1]:=
SystemModel["Modelica.Mechanics.MultiBody.Examples.Loops.Utilities.GasForce2"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

The gas force in a cylinder of a combustion engine is computed as function of the relative distance of the two flanges. It is required that s_rel = flange_b.s - flange_a.s is in the range

0 ≤ s_rel ≤ L,

where the parameter L is the length of the cylinder. If this assumption is not fulfilled, an error occurs. The resulting approximation of the gas pressure is shown in the following figure and depends on both s_rel and the relative velocity v_rel = der(s_rel).

model Modelica.Mechanics.MultiBody.Examples.Loops.Utilities.GasForce

Parameters (5)

L

Value:

Type: Length (m)

Description: Length of cylinder

d

Value:

Type: Length (m)

Description: Diameter of cylinder

k0

Value: 0.01

Type: Volume (m³)

Description: Volume V = k0 + k1*(1-x), with x = 1 - s_rel/L

k1

Value: 1

Type: Volume (m³)

Description: Volume V = k0 + k1*(1-x), with x = 1 - s_rel/L

k

Value: 1

Type: HeatCapacity (J/K)

Description: Gas constant (p*V = k*T)

Connectors (2)

flange_a

Type: Flange_a

Description: Left flange of compliant 1-dim. translational component

flange_b

Type: Flange_b

Description: Right flange of compliant 1-dim. translational component

Used in Components (3)

Cylinder

Modelica.Mechanics.MultiBody.Examples.Loops.Utilities

Cylinder with rod and crank of a combustion engine

CylinderBase

Modelica.Mechanics.MultiBody.Examples.Loops.Utilities

One cylinder with analytic handling of kinematic loop

Engine1bBase

Modelica.Mechanics.MultiBody.Examples.Loops.Utilities

Model of one cylinder engine with gas force