Impact of a free-falling wedge with water: synchronized visualization, pressure and acceleration measurements

A fixed 25 degrees deadrise angle wedge is allowed to fall from a range of heights into static water. A high-speed (up to 5000 frames s(-1)) camera is used to visualize the impact and subsequent formation of jet flows and droplets. Unsteady pressure measurements at six locations across the wedge surface are measured at 10 kHz. Two accelerometers (10g, 100g) are mounted above the apex of the wedge and measure the vertical acceleration. A purpose-built position gauge and analysis of the synchronized video allows the wedge motion to be captured. The synchronization of these data with the digital images of the impact makes it particularly suitable for the validation of computational fluid dynamics simulations as well as theoretical studies. A detailed experimental uncertainty analysis is presented. The repeatability of the test process is demonstrated and the measured pressures are comparable to previous studies. A similar to 2.5 ms time delay is identified between the point of impact observed from the video and the onset of actual wedge deceleration. The clear definition of the free surface provides insight into jet formation, its evolution and eventual breakdown, further assisting with the development of numerical predictions.