Effect of impact angle on liquid droplet impingement erosion

In steam piping systems containing liquid droplets, pipe walls are sometimes damaged by droplet impingement. One of the most important parameters affecting erosion is the impact angle. No research has been conducted on the effect of the impact angle on erosion for pipe steels. In this study, a jet nozzle was used for high pressure impingement tests of S15C, SUS304 and STPA24, and a spray nozzle for tests of pure aluminum. The MaxDER (Maximum Depth of Erosion Rate) for these three steels is expressed as sinn θ and the exponent is 1.2–2.5 for these steels. The jet nozzle tests showed that liquid droplet impingement at 90° on specimen was weakened possibly due to the liquid film formation. The spray nozzle tests revealed that the erosion can be estimated using V=V0 sin θ.