Simscape Reference

Constant Area Pneumatic Orifice
Basic Assumptions and Limitations
• The gas is ideal.
• Specific heats at constant pressure and constant volume, c p and c v , are constant.
• The process is adiabatic, that is, there is no heat transfer with the environment.
• Gravitational effects can be neglected.
• The orifice adds no net heat to the flow.
Dialog Box and Parameters
• “Parameters Tab” on page 1-35
• “Variables Tab” on page 1-36
Parameters Tab
Discharge coefficient, Cd
Semi-empirical parameter for orifice capacity characterization. Its value depends
on the geometrical properties of the orifice, and usually is provided in textbooks or
manufacturer data sheets. The default value is 0.82.
Orifice area
Specify the orifice cross-sectional area. The default value is 1e-5 m^2.
1-35