Numerical investigation on hydraulic performance of backward bend duct buoy

A 3-D mathematical hydrodynamic model was conducted to investigate the regular wave motion on the backward bend duct buoy (BBDB), and it was validated with the theoretical wave surface well. It was used to compute the wave heights in the gas chamber and after the BBDB. It was found that the wave transmission coefficient in the gas chamber increased firstly and then decreased with increasing horizontal duct height or the gas chamber length respectively. However, it after the BBDB decreased firstly and then increased with increasing horizontal duct height or the gas chamber length respectively. The gas chamber length plays a more important role in wave transmission coefficient in the gas chamber than horizontal duct height does. The flow rate per unit width increased firstly and then decreased with the increasing horizontal duct height or gas chamber length respectively.