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Energy effect and erosion mechanism associated with impact on solid surface by waterjet |
1.School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.School of Materials Science and Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China |
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Abstract Using PDPA measurement technique and high-speed photography, the cross-sectional distributions of jet velocity were determined, and the fluctuations of jet stream profile were analyzed. The turbulent waterjet under consideration was produced at jet pressure of 280 MPa. The quartz sand particles were added into waterjet to generate abrasive waterjet to impact Al alloy plates. The resultant surfaces were examined by SEM and a 3D optical profiling system to obtain small-scale profiles. The results indicate that the continuous and concentrated segment of jet stream is significantly responsible for the impact capability of jet stream. The segment is featured by a center valley of turbulent RMS velocity distribution. The fluctuations of jet stream profile in longitudinal direction are statistically represented by gray scale values from high-speed images. The concentration level of jet stream can be described by gray scale values. Due to the cooperative action between high speed sand particles and waterjet, cutting traces, truncation traces and impact traces are evidently presented. The traces are definitely associated with the longitudinal distance between nozzle exit and solid surface.
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Received: 07 November 2012
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