High-speed flows (think: jet engine exhaust, supersonic wind tunnels) don’t just move fast—they twist, compress, and create shockwaves that can throw off even the best pneumatic probes. Calibrating for these conditions isn’t the same as routine checks. Here’s what you need to do differently.

Use a high-speed calibration rig:
Standard rigs top out at 100 m/s, but high-speed probes need calibration up to their maximum operating speed (e.g., 500 m/s for aerospace tests). Look for rigs with:

· Variable nozzle sizes to mimic different flow velocities.

· Pressure transducers with <0.1% full-scale error (more precise than typical 0.5% models).

· Data loggers sampling at ≥10 kHz to capture transient flow spikes.

Account for shockwave interference:
At speeds >343 m/s (supersonic), shockwaves form around the probe tip, altering pressure readings. Calibrate in two phases:

1. Subsonic (0–300 m/s) to establish baseline accuracy.

2. Supersonic (350–1,000 m/s) using a schlieren imaging system to map shockwaves and adjust probe positioning.

Check angular response:
High-speed flows rarely hit probes head-on. Calibrate at angles from -40° to +40° (in 5° increments) to ensure accuracy even when flow is skewed—critical for probes measuring airflow around turbine blades.

Shorten calibration intervals:
High-speed use wears down probe tips faster. If you test at >300 m/s weekly, calibrate every 3 months instead of 6. After a shockwave test (e.g., simulating a engine surge), recalibrate immediately—microscopic tip damage can ruin accuracy.

Pro tip: Use a “master probe” (certified by a national metrology institute) as a reference during in-house checks. It’s cheaper than full recalibration and catches drift early.

Ever struggled with high-speed calibration? Tell us your speed range, and we’ll suggest rig options.