State of art in water jet machining: advances in modulated jet techniques and computational insights

Abstract

Water jet machining (WJM) has gained considerable attention for its efficacy in processing hard-to-machine materials, intricate microstructures, and complex industrial components. This technique has become vital for enhancing productivity, flexibility, and quality in various sectors, including aerospace, automotive, and medical device manufacturing. This paper offers an extensive review of historical and recent developments in water jet generation techniques, focusing on continuous water jet (CWJ) and modulated water jet (MWJ) techniques. The review examines the erosion phenomena during jet–material interaction for both CWJ and MWJ, comparing their disintegration capabilities. MWJ techniques are further explored, including external pulsation methods using slotted discs, vibrating velocity transformers, ultrasonically excited jets, and internal pulsation with self-resonating water jets. The recent advances in self-resonating nozzle designs have improved MWJ efficiency by optimizing the energy and focus of the pulsed jet, thereby enhancing cutting precision and operational efficiency. However, the widespread adoption of these techniques is hindered by limitations in nozzle design and an unclear understanding of the mechanisms behind self-resonating water jets, due to the absence of a standard numerical model that accurately represents flow characteristics, pressure distribution, and velocity profiles. In this context, the current review also highlights the application of computational fluid dynamics analysis to develop high-efficiency nozzles, thereby advancing WJM systems to meet diverse industrial needs. This review seeks to understand MWJ experimentally and pinpoint numerical parameters required for an optimal modeling setup. Achieving this will aid in comprehending complex interactions under various environmental conditions, thus promoting structural optimization and practical industrial applications.