INVESTIGATION OF NATURAL CONVECTION IN CHANNELS BY OPTICAL TECHNIQUES

The aim of this work is to investigate natural convection heat transfer in a vertical channel by applying different optical, index-of-refraction techniques. The channel, consisting of two parallel vertical plates at a given spacing value, was asymmetrically heated at uniform wall temperature. Local heat transfer coefficients and isotherm patterns were obtained by using the schlieren technique and the holographic interferometry technique, separately. Experiments were conducted at DITEC, University of Genova and at the Energetic Dept., University of L’Aquila on the same test section