Analyse d'écoulements liquides ou gazeux en micro-conduites : découplage des incertitudes expérimentales

Analysis of gas and liquid flows in micro-ducts: experimental uncertainties decoupling

Laboratoire de Génie Mécanique de Toulouse - INSA de Toulouse INSAT, Département de Génie Mécanique, 135 avenue de Rangueil, 31077 Toulouse cedex 4

Auteur de correspondance : stephane.colin@insa-tlse.fr

Abstract

The different sources of uncertainty that occur during the experimenlal study of steady flows through micro-duels are analyzed. It is noticed that the lack of precision when measuring the geometrical dimensions of the sections plays a crucial role. A method is proposed to avoid this source of uncertainty. It is illustraled with two examples. The first one is relative to gaseous flows in rectangular micro-ducts. The experiment allows to show the validity of a second-order slip-flow model, for Knudsen numbers up to 0.20, while a classic first-order model is no longer precise above 0.05. The second example is relative to liquid flows in trapezoidal micro-ducts. A deviation from the classic Poiseuille law is clearly revealed. for Reynolds numbers between 10^-1 and 10^-3. A relation between Reynolds and Poiseuille numbers is proposed.