Standoff distance in ultrasonic pulsating water jet

0537245 - ÚGN 2021 RIV CH eng J - Journal Article
Srivastava, M. - Nag, A. - Chattopadhyaya, S. - Hloch, Sergej
Standoff distance in ultrasonic pulsating water jet.
Materials. Roč. 14, č. 1 (2021), č. článku 88. E-ISSN 1996-1944
R&D Projects: GA MŠMT(CZ) LO1406
Institutional support: RVO:68145535
Keywords : pulsating water jet * stainless steel * traverse speed * disintegration depth
OECD category: Mechanical engineering
Impact factor: 3.748, year: 2021
Method of publishing: Open access
https://www.mdpi.com/1996-1944/14/1/88/htm

The water hammer effect is the basis of technologies which is artificially responsible forthe decay of continuous jets. A recently developed technique enhances the pressure fluctuationsusing an acoustic chamber, leading to enhanced erosion effects for various water volume flow rates.The optimum standoff distance for an ultrasonic enhanced water jet is not appropriately estimatedusing an inclined trajectory. The objective of this study is to comprehend the true nature of theinteraction of the standoff distance following the stair trajectory and traverse speed of the nozzle onthe erosion depth. Additionally, it also critically compares the new method (staircase trajectory) thatobeys the variation in frequency of the impingements for defined volume flow rates with the inclinedtrajectory. In this study, at constant pressure (p= 70 MPa), the role of impingement distribution withthe variation of traverse speed (v= 5–35 mm/s) along the centerline of the footprint was investigated.The maximum erosion depth corresponding to each traverse speed is observed at approximatelysame standoff distance (65±5 mm) and decreases with the increment in traverse speed (h= 1042 and47μm atv= 5 and 35 mm/s, respectively). The results are attributed to the variation in the numberof impingements per unit length. The surface and morphology analysis of the cross-section usingSEM manifested the presence of erosion characteristics (micro-cracks, cavities, voids, and upheavedsurface). By varying the water cluster, different impingement densities can be achieved that aresuitable for technological operations such as surface peening, material disintegration, or surfaceroughening
Permanent Link: http://hdl.handle.net/11104/0314981