DETERMINATION OF TRANSFER-COEFFICIENTS BY PSYCHROMETRY

This paper presents a method based on psychrometry for measuring simul taneously heat and mass transfer coefficients in the case of forced co nvective exchanges between air and a body surface. This method is spec ially well adapted to bodies of complex shapes. The theoretical aspect s are described. Errors linked to data treatments and to measurements are discussed. The method is tested for a circular cylinder in cross f low in the following conditions: 3500 < Re < 26 000, Tu = 12%, T(air) = 25-degrees-C. Discussion shows that errors can be reduced to less th an 2% for mean transfer coefficients and less than 5% for local coeffi cients.