Experimental investigations into heat transfer and fluid flow characteristics of a solar air heater having its duct packed with wire mesh screen matrices were carried out. The investigations covered a wide range of geometrical parameters of wire mesh screen matrix (wire diameter, pitch and number of layers). Generalized correlations have been developed for heat transfer coefficient and friction factor for air flowing through the bed of wire mesh screen matrix packed in the solar air heater duct in a cross flow arrangement. Correlations developed for Colburn J-factor and friction factor indicate that heat transfer coefficient and friction factor are strong functions of geometrical parameters of matrices. These correlations have been found to predict the experimental data with reasonable accuracy.