Study of the efflux velocity induced by two propellers
Document typeConference report
Rights accessOpen Access
Present analysis is related with seabed erosion caused during docking and undocking maneuvering. Twin propellers without rudder were studied using a physical model with a fixed clearance distance and three different rotating velocities. Experimental results were compared to theoretical expressions of the efflux velocity, axial velocity and finally maximum bed velocity. Efflux velocity equations overestimate the experimental results, whereas axial velocity computed using the Dutch method fits reasonably well the experimental data. However, when maximum bed velocity expressions are compared to experimental results, German method behaves better with an over estimation if a quadratic superposition of the single jets is used.
CitationMujal -Colilles, A., Gironella, X., Jaquet, A., Gómez-Gesteira, M., Sanchez-Arcilla, A. Study of the efflux velocity induced by two propellers. A: International Short Course and Conference on Applied Coastal Research. "Proceedings of the 7th International Short Course and Conference on Applied Coastal Research: SCACR2015". Florència: EdiBios, 2015, p. 125-134.