📏 Pitot Tube & Pitot-Static Probe Calculator
Measure flow velocity from total and static pressure readings. Includes Bernoulli incompressible and isentropic compressibility correction for M > 0.3.
🔬 Pitot-Static Probe Schematic
📝 Configuration
Key Equations:
Bernoulli: V = √(2ΔP/ρ)
Isentropic: Pt/Ps = (1+(γ−1)/2 M²)γ/(γ−1)
V = M·a; a = √(γRT)
Correction = Vcomp/Vincomp
Bernoulli: V = √(2ΔP/ρ)
Isentropic: Pt/Ps = (1+(γ−1)/2 M²)γ/(γ−1)
V = M·a; a = √(γRT)
Correction = Vcomp/Vincomp
📊 Results
Configure inputs and click Compute to view results.
📘 Methodology
Bernoulli vs Compressible
For M < 0.3, Bernoulli's incompressible equation gives less than 2% error. Above M = 0.3, the isentropic pressure-Mach relation must be used to avoid significant velocity underestimation.
Correction Factor
The ratio Vcomp/Vincomp quantifies how much the incompressible assumption over- or under-estimates the true velocity. The chart shows this divergence as ΔP increases.
Assumptions
- Steady, one-dimensional flow at probe location.
- Perfect gas with constant γ.
- No probe interference or alignment error.
- Subsonic isentropic relation (no normal shock for M > 1).