Cauchy Number
The Cauchy Number is a dimensionless value useful for analyzing fluid flow dynamics problems where compressibility is a significant factor.
The Cauchy Number is the ratio between the inertial force and the compressibility force in a flow and can be expressed as
C = ρ v2 / E (1)
where
C = Cauchy Number
ρ = density (kg/m3)
v = flow velocity (m/s)
E = bulk modulus elasticity (N/m2)
The bulk modulus elasticity has the dimension pressure and is commonly used to characterize the compressibility of a fluid.
The Cauchy Number is the square of the Mach Number
M2 = C (2)
where
M = Mach Number
Related Topics
• Fluid Mechanics
The study of fluids - liquids and gases. Involving velocity, pressure, density and temperature as functions of space and time.
Related Documents
Bulk Modulus and Fluid Elasticities
Introduction to - and definition of - Bulk Modulus Elasticity commonly used to characterize the compressibility of fluids.
Density vs. Specific Weight and Specific Gravity
An introduction to density, specific weight and specific gravity.
Mach Number
An introduction to the Mach Number.