Authors: A.T. Basha; M. Annoni; M. Monno; F. Inzoli
Addresses: Dipartimento di Meccanica, Politecnico di Milano, 20156 Milan, Italy ' Dipartimento di Meccanica, Politecnico di Milano, 20156 Milan, Italy ' Dipartimento di Meccanica, Politecnico di Milano, 20156 Milan, Italy ' Dipartimento di Energia, Politecnico di Milano, 20156 Milano, Italy
Abstract: Cutting heads are core components of abrasive water jet cutting plants which dramatically affect the achievable cutting performance. Therefore, investigating their characteristics to achieve an efficient design is fundamental to improve the AWJ technology. In this study, computational fluid dynamics models for ultrahigh velocity waterjets and abrasive waterjets are established using ANSYS FLUENT® software. Jet flow dynamic characteristics inside a cutting head are simulated under unsteady state, turbulent, two-phase and three-phase flow conditions. Water and particles velocities are obtained under different operating conditions to provide an insight into the jet characteristics and study the effect of cutting head geometry. The comparison with experimental data shows the accuracy of the numerical simulations in predicting cutting head performance, as well as revealing the effect of operating conditions. Moreover, the fact that results obtained with two different geometrical models (2D-axisymmetric and 3D) are similar reveals that the flow pattern does not depend much on the position of the abrasive and air suction zone. This investigation aids the understanding of the flow inside the AWJ cutting head and provides information for designing this component to suit optimum performances.
Keywords: abrasive water jets; hydrodynamics; AWJ cutting heads; cutting head design; computational fluid dynamics; CFD; jet flow dynamics; numerical simulation; geometrical modelling; flow pattern.
International Journal of Machining and Machinability of Materials, 2013 Vol.14 No.1, pp.105 - 122
Received: 08 May 2012
Accepted: 24 Nov 2012
Published online: 26 Dec 2013 *