WOLFRAM SYSTEMMODELER

Engine1bBase

Model of one cylinder engine with gas force

Diagram

Wolfram Language

In[1]:=
SystemModel["Modelica.Mechanics.MultiBody.Examples.Loops.Utilities.Engine1bBase"]
Out[1]:=

Information

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

This is a model of the mechanical part of one cylinder of an engine. The combustion is not modelled. The "inertia" component at the lower left part is the output inertia of the engine driving the gearbox. The angular velocity of the output inertia has a start value of 10 rad/s in order to demonstrate the movement of the engine.

The engine is modeled solely by revolute and prismatic joints. Since this results in a planar loop there is the well known difficulty that the cut-forces perpendicular to the loop cannot be uniquely computed, as well as the cut-torques within the plane. This ambiguity is resolved by using the option planarCutJoint in the Advanced menu of one revolute joint in every planar loop (here: joint B1). This option sets the cut-force in direction of the axis of rotation, as well as the cut-torques perpendicular to the axis of rotation at this joint to zero and makes the problem mathematically well-formed.

An animation of this example is shown in the figure below.

model Examples.Loops.Engine

Components (12)

Piston

Type: BodyCylinder

Rod2

Type: BodyBox

Bearing

Type: Revolute

world

Type: World

Inertia

Type: Inertia

Crank4

Type: BodyBox

Crank3

Type: BodyCylinder

Crank1

Type: BodyCylinder

Crank2

Type: BodyBox

Mid

Type: FixedTranslation

cylPosition

Type: FixedTranslation

gasForce

Type: GasForce2

Extended by (2)

Engine1b_analytic

Modelica.Mechanics.MultiBody.Examples.Loops

Model of one cylinder engine with gas force and analytic loop handling

Engine1b

Modelica.Mechanics.MultiBody.Examples.Loops

Model of one cylinder engine with gas force and preparation for assembly joint JointRRP