Simple models for laminar thermally developing slug flow in non-circular ducts and channels

Journal article

Solutions to the classical Graetz slug or plug flow problem in non-circular ducts are examined. These solutions have applications where a constant uniform velocity distribution exists across a channel or duct. These are most often realized in the laminar flow of low Prandtl number liquids, such as liquid metals, and low Reynolds number flows through porous media. Expressions are developed for a number of applications using the asymptotic correlation method of Churchill and Usagi. These expressions vary depending on the definition used for the dimensionless heat transfer coefficient in the case of constant wall temperature boundary condition (T), and the dimensionless wall temperature for the constant flux boundary conditions, (H) and (H1). Finally simple expressions are developed for predicting the thermal entrance length and fully developed flow Nu values for non-circular ducts. Copyright © 2010 by ASME.

Authors: Muzychka, Y; Walsh, E; Walsh, P

• Publisher: American Society of Mechanical Engineers (ASME)
• Journal: ASME International Mechanical Engineering Congress and Exposition, Proceedings
• Volume: 9
• Issue: PART C
• Pages: 1867-1878
• Publication date: 2010-01-01
• DOI: 10.1115/IMECE2009-10484
• Language: English
• Keywords: Slug flow; Modelling; Laminar flow; Heat exchangers; Plug flow; Heat transfer coefficient; Heat sinks; Graetz flow; Porous media