This isentropic flow calculator finds the stagnation-to-static ratios of pressure, density, and temperature for compressible flow from the Mach number. Enter the Mach number (and gamma) above.
Formulas (ratio of specific heats γ)
T₀/T = 1 + (γ−1)/2 × M² P₀/P = (T₀/T)^(γ/(γ−1)) ρ₀/ρ = (T₀/T)^(1/(γ−1))
Example (γ = 1.4, M = 0.8)
T₀/T = 1.128, P₀/P = 1.524, ρ₀/ρ = 1.351.
Related calculators
Frequently Asked Questions
What are isentropic flow relations?
They link static and stagnation pressure, density, and temperature to Mach number for reversible, adiabatic compressible flow.
What is gamma in these equations?
Gamma is the ratio of specific heats, about 1.4 for air at normal conditions.
When do isentropic relations apply?
For adiabatic, reversible flow with no shocks or friction, a good model for nozzles and diffusers.