Optimisation of Hydrofoiling Bike

Abstract

This research aimed at optimising the hydrofoils currently employed on the Hydrofoiler XE-1 water bike, which was developed by Manta5. This involved identifying improvement areas of the current hydrofoils and comparing their performance to those of the optimised proof of concept design developed for this research. To fulfil this aim, an experimental and numerical methodology was followed to obtain the current hydrofoil’s benchmark performance results. Wind tunnel testing was conducted on the hydrofoil models, with the results being compared to analytical models and other results obtained from the literature. With the suitability of the experimental results outlined, computational fluid dynamics (CFD) simulations were conducted to assess the reliability of these numerical models compared with the benchmark results. With good agreement across these different models, the numerical procedure was validated as a design tool for the optimisation process. The optimisation process was conducted on the rear hydrofoil as it was identified as the foil with the most potential for performance improvements. An analytical procedure was first developed to filter through an extensive range of different profile shapes, with the best performing profiles with the largest lift to drag ratio identified at the intended operating condition. These were then analysed using the CFD models validated earlier for a more comprehensive assessment of the foil performance. From these results, the final proof of concept design was developed for the rear foil. The design has a tapered planform with a span, aspect and taper ratio of 2𝑚, 10 and 0.4, respectively. The SD7037 profile was identified through the optimisation process to be the best performing profile with performance improvements ranging from 14 − 41.9 % and 11.5 − 21.2 % for the minimum and maximum design weights, respectively, when compared with the current rear hydrofoil of the Hydrofoiler XE-1. While further experimental testing is recommended to validate these results, the performance improvements of this proof of concept design are evident. In addition to these results, the design procedure has also been documented for future use by Manta5.