Wake Frequency Calculator
Evaluate vortex-induced vibration risk for thermowell and sensor insertions per ASME PTC 19.3 TW-2016. Calculates shedding frequency, natural frequency, and PASS/FAIL assessment for both lift and drag directions.
1Fluid Properties
2Dimensions
3Material
4Sweep Range
Configure parameters and click Calculate
About This Calculator
Evaluates vortex-induced vibration (VIV) risk for thermowell and sensor insertion assemblies per ASME PTC 19.3 TW-2016.
When fluid flows past a cylinder, alternating vortices are shed at the vortex shedding frequency (f_s). If f_s coincides with the natural frequency (f₁), resonance can cause fatigue failure.
Standards: ASME PTC 19.3 TW-2016 · ASME B31.3 · API RP 551 · IEC 61518
Frequently Asked Questions
What is wake frequency?
The frequency at which vortices shed from a cylinder in cross-flow: f_s = S·V/D.
What is the Strouhal number?
A dimensionless number (S ≈ 0.2 for Re 1k–100k) describing oscillating flow. Varies at higher Re per ASME PTC 19.3.
When does a thermowell fail?
When f₁ falls within the resonance zone of f_s in lift or drag direction, including ±30% safety margin.
How to fix a FAIL?
Increase wall thickness, shorten unsupported length L, use stiffer material, or reduce flow velocity.
Need Engineering Support?
Our engineers can help you select the right thermowell and verify your installation against ASME PTC 19.3 TW.