Analysis of the flow through a circular-to-semicircular cooling baffle bend

• Published in: Proceedings of the Institution of Mechanical Engineers. Part C, Journal of mechanical engineering science Vol. 214; no. 2; pp. 389 - 397
• Main Authors: Van der Walt, J P, Morsi, Y S
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.01.2000; Mechanical Engineering Publications; SAGE PUBLICATIONS, INC
• Subjects: Computational fluid dynamics; Condensed matter: structure, mechanical and thermal properties; Cooling; Cooling water; Correlation methods; Cross-disciplinary physics: materials science; rheology; Deformation; material flow; Exact sciences and technology; Flow of water; Injection molding; Mathematical models; Mechanical and acoustical properties of condensed matter; Mechanical properties of liquids; Physics; Plastics molding; Pressure drop; Rheology; cooling circuit; baffles; plastic injection moulding; pressure losses; Experimental test; Fluid dynamics; Computational fluid dynamics; Flow pattern; Numerical method; Water flow; Cooling circuit; Experimental study; Cooling by water; Inelasticity; Baffles; Dimensional analysis; Plastic mold; Injection molding; Pressure loss; Elbow
• ISSN: 0954-4062; 2041-2983
• DOI: 10.1243/0954406001523056

Abstract The cooling of moulds through the usage of baffles is commonplace in the plastic injection moulding industry. The flow of cooling water through the baffle entrance experiences a sharp 90° bend as well as a circular-to-semicircular geometry change. As it is apparent from the literature that no pressure loss relationships are available, an experimental test rig was constructed to enable these losses to be measured. Furthermore, a numerical model was constructed through the use of computational fluid dynamics to assist in the development of these correlations. This paper discusses this flow problem and develops a new empirical correlation using dimensional analysis for the sharp circular-to-semicircular elbow entrance of the cooling baffle of a plastic injection mould. It was found that the empirical relationship predicts the pressure losses with good accuracy.