Forces and fluid dynamics in the sport of rowing
Nicholas Elton
As a rower, I wanted to understand what truly makes a rowing boat move fast? This essay uncovers areas surrounding telemetry and fluid dynamics covering forces surrounding the spoon of the blade. Professional rowing is often traced back to races between the upper class, living on the banks of the River Thames and the working class, whose jobs centred around rowing boats across the river. Since 1715, rowing has gone from transportation to an Olympic sport. Successful rowing is a combination of 90% rower and 10% equipment: boat, oars, coaching and telemetry. In the 2020 Olympics, there was less than one second difference between first and second place in the Men’s Eight competition. Over the course of two thousand metres, each engineering innovation can provide a competitive edge where the sport today is arguably at a glass ceiling. Driving technological progress in rowing is understanding how human biomechanics link into the physical forces to drive the boat forward with maximum efficiency. This essay will endeavour to explore the analysis of a rower’s telemetry and its benefits, of forces on the oar and their effect on the boat as a whole. Furthermore, the shape of the boat and oars will be scrutinized with respect to vortex-shedding and the impact of different fluid viscosity. Turbulent and laminar flow will be considered. This research will answer the question: what makes a rowing boat move fast?
Telemetry
On a rower’s gate, telemetry uses sensors to determine a rower’s power output during each stroke. As seen in Figure 1, the left hand side graph shows the average curve for Gate Force versus Gate Angle for eight individual rowers over two thousand metres. Gate force is presented as kilogram- force, which is equal to the magnitude of the force exerted on one kilogram of mass in a gravitational field. Gate angle is measured from perpendicular
Figure 1: Telemetry from the Dulwich College 1 st 8, 03/06/24
with the boat, a typical rower will row sixty degrees forwards of the perpendicular (presented as negative on the graph) and forty degrees to the back. The area under each graph is proportional to power exerted by a rower each stroke. As shown in Figure 1, the ability to compare each individual curve with one another including point of peak and overall power output allows for coaches to gain insight into how a rower can improve and make informed decisions when choosing a crew. Finally,
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