Selecting pitot probes for high-speed wind tunnels (>500m/s, Ma >1.5) needs focus on shock wave management material heat resistance and dynamic response—key for accuracy in supersonic flow.5-Hole Pitotwelcome to click on the website to learn more!
Shock wave behavior decides probe head design a sharp cone (15°-20° half-angle) keeps shocks attached which are stable, blunt heads create detached shocks causing 5-10% pressure error. A wind tunnel test at Ma 2.0 found 18° cone probes had 3% lower error than 30° ones due to more stable shock attachment.
Material heat resistance is critical aerodynamic heating at 500m/s can make probe tips 300-500°C. Inconel 718 (works up to 800°C) is better than stainless steel a 500-hour test at 400°C showed no oxidation, 316 stainless steel got a 0.1mm oxide layer changing hole sizes.
Dynamic response time must be <5ms to catch transient supersonic features (like shock reflections). Thin-walled probes (0.5-1mm) respond faster than thick ones a test found a 0.8mm Inconel probe detected a shock 3ms earlier than a 2mm one, improving data.
Calibration in a supersonic jet (Ma 1.5-3.0) is needed subsonic calibration underpredicts pressure from shocks. A lab found probes calibrated only at subsonic speeds had 8% error in supersonic flow, those calibrated across all speeds had <1% error.