Numerical study of the heat and momentum transfer between a flat plate and an impinging jet of power law fluids

• Type: Article in International Scientific Journal
• Date: 2019-06-24

Authors

J. Ortega-Casanova (Author) Other; M. Jimenez-Canet (Author) Other; F. J. Galindo-Rosales (Author) FEUP

Journal

Title: International Journal of Heat and Mass Transfer

Vol. 141

Pages: 102-111

ISSN: 0017-9310

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

ISI Web of Science

Scopus - 3 Citations

Other information

Authenticus ID: P-00Q-RBC

DOI: 10.1016/j.ijheatmasstransfer.2019.06.072

Abstract (EN): In this paper we analyse the jet of non-Newtonian power law fluids emerging from a tube with a diameter D and impinging on a flat plate, which is receiving from the other side a constant heat flux. To that end, different numerical simulations have been carried out with the one dimensional fully developed axisymmetric velocity profile used as boundary condition to model the jet. The aim of the work is to quantify the heat (through the Nusselt number) and momentum (through the friction coefficient on the plate) transfer processes between the jet and the plate as a function of the Reynolds number (Re = 50, 100, 200), the tube-to-plate distance (H/D = 1, 2 ; 4) and the power law index (n = 0.8, 0.9, 1.0, 1.1, 1.2). The values given to the power law index allowed to explore both the shear thickening and the shear thinning behaviours. Results showed that a larger tube-to-plate separation decreases both the transference of heat and momentum; additionally, increasing the Reynolds number improves the heat transfer in detriment of momentum transfer; and, similarly to this latter input parameter, lowering the power law index, increases the heat transfer and worsens the momentum transfer. These results are summarised in three mathematical correlations consisting of potential functions of the input parameters, i.e. Re, H/D and n. However, as it is usually done, the Prandtl number Pr will be used instead of n. (C) 2019 Elsevier Ltd. All rights reserved.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10