This study investigates the influence of multiple jet parameters on the flow field of translating impinging inclined water jets. We conducted full-scale stereoscopic particle image velocimetry and pressure measurements and three-dimensional computational fluid dynamics simulations for Reynolds numbers in the range of. Considering the complex mechanism of a translating impinging jet, a good concordance is observed between the experimental and numerical results. The translation-to-jet velocity ratio is identified as a critical parameter in determining whether the jet flow predominantly exhibits impinging characteristics or behaves as a jet in cross-flow. It is found that, for, jet impingement is minimal. The stand-off distance to nozzle diameter ratio determines the relative influence of the cross-flow on the jet flow. The effect of is similar to a stationary impinging jet, with the potential core extending up to, but entrainment is enhanced by the relative cross-flow. For an inclined jet, i.e. jet angle, the direction of the jet, either backward or forward, governs the deflection of the flow. Higher pressures are recorded for a backward directed jet compared with a forward directed jet for supplementary angles.

Very limited research has been carried out to investigate sediment erosion caused by subaqueous inclined water jets, despite the fact that such water jets are used in subsea engineering (e.g., dredging, trenching, and deep sea mining). Therefore, we conducted a set of novel small-scale experiments to primarily study the effect of jetting inclination on cohesive sediment erosion. The experimental results reveal that vertical jetting results in the largest cavity depth (or ’erosion depth’), but not in the largest cavity size (sediment production). The erosion depth increases with the jetting angle reaching its maximum at 90° and then begins to decrease with further increase in the jetting angle. The results also indicate that the cavity width (or ’erosion width’) is not necessarily correlated with the impingement region but is instead associated with the erosion-effective jet width—the width of the jet where flow velocities are high enough to penetrate the bed. Analysis of the cavity size showed that the largest sediment production was achieved at a 65° jetting angle among the tested jetting angles (25°, 45°, 65°, 90°, 115°, 135°, and 155°). The erosion depth was found to be highly proportional to the impingement force exerted by the flow on the clay.