Micro pitot probes (diameter <5mm) are essential for measuring flow in confined spaces like small engine manifolds or microfluidic devices, but their size introduces unique design and manufacturing challenges.Sensor Calibrationwelcome to click on the website to learn more!
Structural rigidity is a primary concern. A 3mm diameter probe with a 50mm stem (L/d=16) risks bending in turbulent flow, increasing measurement error by up to 4%. Reinforcing the stem with a 0.5mm tungsten core improves rigidity without excessive weight gain, as demonstrated in a micro-turbine test where reinforced probes maintained alignment 3x longer than unreinforced ones.
Hole drilling precision is critical. Laser drilling (±0.01mm tolerance) ensures hole symmetry, whereas mechanical drilling often results in off-center holes, leading to pressure imbalance. A comparison test found laser-drilled micro probes had 2% lower error than mechanically drilled ones in low-speed flow.
Material selection prioritizes strength-to-weight ratio. Titanium (TC4) is preferred over stainless steel for its lower density (4.5 g/cm?? vs. 7.9 g/cm??), reducing airflow disturbance in narrow channels. In a 4mm diameter pipe test, a titanium probe caused 15% less pressure drop than a stainless steel probe of the same size.
Calibration requires micro-scale reference standards. Using a 1mm diameter calibration nozzle ensures accurate low-flow readings, as standard-sized nozzles fail to simulate the confined conditions these probes encounter. A research lab found that calibration with micro nozzles reduced field measurement error by 30%.