Determination of the Coefficient of Transverse Dispersion in Beds of Sandfor a Wide Range of Temperatures (50 < Sc < 1200)

• Type: Article in International Conference Proceedings Book
• Date: 2000

Authors

João R. F. Guedes de Carvalho (Author) FEUP; João Quesado Delgado (Author) FEUP

Conference proceedings International

Title: International Symposium on: Multiphase Flow and Transport Phenomena

International Symposium on: Multiphase Flow and Transport Phenomena (MFTP-2000)

Antalya, 5 a 10 de Novembro de 2000

Other information

Abstract (EN): The coefficient of transverse dispersion in flow through packed beds, was determined by means of a method which is based on the measurement of the rate of dissolution of plannar or cylindrical surfaces, buried in the bed and aligned with the flow direction. The soluble solids used in our experiments were benzoic acid and 2− naphtol and the range of temperatures covered was 273 К− 373 К, which means that the Schmidt number (Sc) varied in the range 50-1200. These data are for the flow of water, at interstitial velocities (U) between 0.1 and 13 mm/s, through beds of silica sand with average particle sizes between 0.219 and 0.496 mm. The data obtained are reported as the ratio between the coefficient of transverse dispersion (D T) and the coefficient of molecular diffusion (D m), and plots of this ratio as a function of the Peclet number (Pe m) bring into evidence the influence of Sc on transverse dispersion; for Sc greater than about 550, all the data fall on a single line, whereas for lower Sc, different lines are obtained for different values of Sc. As expected," gas behaviour" is gradually approached as Sc is decreased.

Language: English

Type (Professor's evaluation): Scientific