packageExercise3OttoEngine

Information

This example package illustrates stationary-flow representations of closed-system Otto (s, v, s, v) engine processes. Here, s denotes an isentropic process (or more general an adiabatic process with isentropic efficiency) and v denotes an isochoric process (constant specific volume/density).
The examples differ with respect to the following aspects:

• The process model: the PolytropicPerfectGas process model allows to set the outlet density, while the Adiabatic process model only allows to set the outlet pressure.
• The medium model: the SimpleAir medium (perfect gas with constant cp) versus the DryAirNasa medium (ideal gas with temperature-dependent cp).

English problem description

A four-stroke Otto engine can be represented by the following idealized thermodynamic cycle:

• 1 → 2: Isentropic compression (T1 = 300 K, p1 = 1.00 bar, compression ratio phi = 10.0)
• 2 → 3: Isochoric heat addition (combustion process, T3 = 2200 K)
• 3 → 4: Isentropic expansion (with V4 = V1)
• 4 → 1: Isochoric heat rejection (in practice realized via gas exchange of the displaced volume)

Contents

Name	Description
PolytropicCycle
PolytropicFlow
AdiabaticPerfectGas
DryAirNASA
DryAirNASAPseudoInversion
BaseModel

Revisions

• 2026, by Raphael Gebhart (raphael.gebhart@dlr.de):
  Initial version.