Experimental Analysis of Multiphase Flow in Metallic foam: Flow Laws, Heat Transfer and Convective Boiling

• Published in: Advanced engineering materials 2006-09, Vol.8 (9), p.890-899
• Main Authors: Topin, F., Bonnet, J.-P., Madani, B., Tadrist, L.
• Format: Article
• Language: English
• Subjects: Cellular metals; Cross-disciplinary physics: materials science; rheology; Deformation; material flow; Engineering Sciences; Exact sciences and technology; Flow laws; Fluids mechanics; Mechanics; Physics; Rheology; Transport properties
• ISSN: 1438-1656; 1527-2648
• DOI: 10.1002/adem.200600102

The first part of this work deals with flow laws of gas, liquid and mixtures in metallic foam. This experimental work is based on the stationary pressure profile measurement in a channel filled with metallic foam of several grades or materials for several controlled flow rates. Several foam samples with different characteristics (10, 40, 60, 100 ppi) of copper and of nickel are studied. In single‐phase conditions, we evaluate the permeability and inertial the coefficient according to the Forchheimer model. In the gas flow case, compressibility effects are taken into account. Emphasis is given on the relative contributions of inertial and viscous effects. The specific behavior linked to compressibility effect is thoroughly studied. The adiabatic (air‐water) conditions are analyzed; the results are reported in term of biphasic multipliers according to a simple homogeneous model, to study the impact of foam texture and gas quality on flow laws. Several aspects of the two‐phase flow case (i.e. liquid‐vapor) are discussed: phase repartition, pressure drops, characteristic boiling curve …. In single phase conditions, the heat transfer coefficient was improved by two orders of magnitude with the presence of metallic foam with only a limited increase in pressure drop. In biphasic conditions, the study of convective boiling regime also showed significant heat transfer enhancement with very low‐pressure drops. A simple one dimensional homogeneous model was used and allows a good description of global flow behavior across the test section. Permeability and inertial coefficient are obtained using stationary pressure profile measurement in a channel filled with various metallic foams. Compressibility effects are studied. In single phase, heat transfer is X 100 with only a limited increase of pressure drop. Convective boiling regime showed significant heat transfer enhancement with very low‐pressure drop. Global flow behavior across the test section is described by 1D homogeneous model.