Modelling the effect of air inclusions on pressure dynamics in a twin-piston cylinder

In this example, the model demonstrates the effects due to air inclusions in the fluid during the operation of a twin-piston cylinder. The absolute pressure does not drop below zero because the bulk modulus of elasticity of a homogeneous gas-liquid mixture decreases correspondingly at low pressures.

Schematic of the model:

Simulation results:

Cylinder pressures as a function of time:

Blocks used in example

• Local Restriction (IL)
• Isothermal Liquid Properties (IL)
• Absolute Pressure Sensor (IL)
• Translational Velocity Source
• Sine Wave Function