FORCED CONVECTION AND EFFECTIVE TRANSPORT PROPERTIES IN PACKED BEDS

摘要

This paper reports the results of experimental investigation of thermally developed forced convective heat transfer to fluid flowing through vertical electrically heated tube of diameter D =52 mm packed with spherical glass particles. The experiments were carried out for water and 47%-glycerine aqueous solution as a working fluid and ratio of the particle diameter to the tube diameter d of 0.017, 0.062 and 0.17. Radial temperature profiles inside the bed have been measured at axial position x/D of 8.01 and 9.03. A two-dimensional quasi-homogeneous model was employed to obtain overall heat transfer coefficients, as well as effective thermal conductivities and apparent wall heat transfer coefficients. New correlations for the thermal conductivity at high Peclet numbers and the heat transfer coefficients at medium Reynolds numbers (inertial flow regime) are developed.