This research paper proposes the use of empirical equations to estimate the temporal maximum scour induced by twin-propeller (ɛ_twin=Ω_t [ln(t)]^(Г_t )) when acting over non-cohesive bed materials. A purpose-built experimental apparatus is used to obtain the measurement data required for the calculation of the empirical constants. The output from rigorous experimental investigations demonstrates that the maximum scour depth produced from the operation of twin-propeller (ɛ_twin), within the confines of a harbour basin, varies as a logarithmic function of time. A dimensional analysis of the standard single propeller configuration is used as the foundation upon which the scour equation is postulated. This is extended to include, for the first time, the influence of the operating distance between the twin-propeller configurations. The division of scours by twin-propeller and single-propeller (ɛ_twin/ɛ_m) enables the establishment of mathematical relation to calculate C1, C2, A and B. The constants are C_1=366.11, C_2=0.3376, A=-0.859 and B=0.1571. The proposed scour equation is more reliable within the time zone up to 2 hours based on the experimental data.
|Number of pages||18|
|Journal||Journal of Marine Science and Engineering|
|Publication status||Published - 27 Sep 2019|
- Ship twin-propeller; scour depth; empirical model, 3D printing