Transferts thermiques convectifs en mini-canal : confrontation calculs/mesures

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We present a series of measurements of the friction factor and the forced convection heat transfer coefficient in 2D mini-channels of 1.12 mm to 300 µm in thickness. The friction factor is estimated from the measurement of the pressure drop along the whole channel. The heat transfer coefficient is determined from a local and direct measurement of the temperature and the heat flux at the wall by means of a specific transducer. The experimental results do not lead to question the validity of the classical correlations obtained on ducts of larger size. The numerical simulations have shown that the deviations observed from the classical laws for both the friction factor and the Nusselt number are mainly due to macroscopic effects as entrance effects or the lack of uniformity of the surface heat flux.