Compressible and incompressible

Kremella

Hello everyone, can someone tell me what is the difference between compressible and incompressible flows? Is it just to refer to gaseous and liquid flow?

prajput

Hi, while fluids and gases have different compressibility, both can be assumed to be incompressible under certain circumstances. An incompressible flow is defined as a constant density flow, while a compressible flow is defined as a variable density flow.

kkanade

Adding to response, in a fluid moving at a Mach number of a flow is lower than 0.3 the variations of density are small and the fluid can be assumed to be incompressible. If M>0.3 the fluid can be assumed to be compressible.