Method and system for determining flow properties of a fluid flowing along a surface

US12411152B2 · kind B2 · utility

Assignees

• AIRBUS OPERATIONS LIMITED · DE
• AIRBUS (S.A.S.) · FR
• Ostbayerische Technische Hochschule · DE

Inventors

• Alois Friedberger · Hamburg, DE
• Bruno Stefes · Hamburg, DE
• Dominik Berndt · Regensburg, DE
• Rupert Schreiner · Regensburg, DE

Key dates

• Filing date: Mar 23, 2023
• Grant date: Sep 9, 2025
• Expiry date: Aug 30, 2043

Classification

• Technology area (CPC G): Physics
• CPC primary: G01P5/12
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for determining flow properties of a fluid flowing along a surface by: modulating the current through a heating element of a thermal flow sensor located on the surface with at least one modulation frequency, thereby emitting a thermal wave into the fluid flowing along the surface having a penetration depth inversely proportional to the modulation frequency; measuring an amplitude of a voltage across the heating element at the third harmonic of the at least one modulation frequency, the voltage depending on the thermal conductivity and the volumetric heat capacity of the fluid flowing along the surface; determining a flow velocity at the penetration depth from the attenuation value of the determined amplitude of the voltage; and estimating whether the flow at the penetration depth is laminar or turbulent on the basis of the determined flow velocity. Also, a system and an aircraft with such a system.