Difference between System and Control Volume in Thermodynamics
Contents
Comparison between System and Control Volume
Difference between System and Control Volume

Comparison Chart
System | Control Volume |
---|---|
A system is a defined quantity of matter which is considered to analyze the problem. | A system is a defined quantity of matter which is considered to analyze the problem. |
The system is separated from its surrounding by a boundary which may be real or imaginary and may change shape, volume, and position relative to an observer. The C.V. is separated from its surrounding by a control surface which may be real or imaginary and normally fixed in shape & position relative to an observer. | The C.V. is separated from its surrounding by a control surface which may be real or imaginary and normally fixed in shape & position relative to an observer. |
Control Volume
- In a thermodynamic analysis of an open system, such as an air compressor, turbine, etc. attention is focused on a certain volume in space surrounding the system, known as control volume.
- The control volume bounded by the surface is called “Control Surface”.
- Both mass and energy can cross the control surface. It may be physical or imaginary.