Measurement of the Impact Force and Pressure of Water Jets under the Influence of Jet Break‐up

Abstract Using a new test setup, the results for the mechanical impact force and pressure of water jets of a nozzle in tubular form with different nozzle diameters (3, 4 mm), gauge pressures (1 – 6 bar) and stand‐off distances (0.5 – 5 m) are presented. It is shown that the stand‐off distance and, thus, the jet break‐up has a significant influence on the mechanical forces of water jets. An optimum stand‐off distance with regard to the maximum impact force and pressure was determined in the range of 2 – 2.5 m. As a result, a semi‐empirical equation for the description of the mean impact force was derived.