A computational fluid dynamic investigation of rowing oar blades

This thesis describes the application of computational fluid dynamics (CFD) to model the flow regime around rowing oar blades. The two phase flow that was present at the surface between the water and the air was also incorporated into the CFD model. Firstly, a quasi–static method was applied, whereby the blade was held at a discrete number of angles of attack to the oncoming flow. The performance of the model was assessed by applying it to four scaled oar blade designs and validating results against an experimental data set. The results were encouraging with lift and drag coefficients acting on the blades being well predicted throughout. The scope was extended to include full size oar blades of designs typically found in competition rowing. A second approach to investigating the flow around oar blades was also adopted, where instead of being held stationary, the blades moved in the fluid domain. The unsteady effects induced by this rotational motion were found to be substantial, with a 72% and 67% increase in the lift and drag coefficients respectively. Finally, through coupling the CFD predictions of oar blade force coefficients with a mathematical model of rowing, it was possible to determine the influence of oar blade design on rowing performance, and also use the mathematical model to further validate the CFD predictions against on–water data. The results provided an accurate assessment of boat performance during the rowing stroke