# CFD Prediction of the Effect of Appendages and Leeway on the Force Trend of an Olympic Class Laser Dinghy Hull

### Rickard Lindstrand, Jeremy Peter, Christian Finnsgård

#### Abstract

The purpose of this paper is to investigate whether the minima in hydrodynamic resistance can be predicted to occur at the same angles of heel and trim in the case of bare hull towing tank tests, bare hull simulations and appendage and leeway simulations. If so, the appendages and the leeway can be rejected from future investigations, which would prove a beneficial advancement, as they impose further complexity to simulations. The results of verification and validation (V&V) included in this paper demonstrate that the numerical method predicted too low resistance. Though the study identifies and systematically investigates possible sources of error, the major source of error was not found. These various possible sources of errors were identified for further research, and as future references for similar cases. Moreover, the simulation results for the variations of heel and trim also require further study. Before a full set of results is available, one cannot make conclusions regarding the angles of heel and trim that lead to minimal resistance. This paper discusses the results and potential avenues of future research, and is a result of an initiative at Chalmers University of Technology focusing on sports and technology.

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#### Paper Citation

#### in Harvard Style

Lindstrand R., Peter J. and Finnsgård C. (2014). **CFD Prediction of the Effect of Appendages and Leeway on the Force Trend of an Olympic Class Laser Dinghy Hull** . In *Proceedings of the 2nd International Congress on Sports Sciences Research and Technology Support - Volume 1: icSPORTS,* ISBN 978-989-758-057-4, pages 190-202. DOI: 10.5220/0005191101900202

#### in Bibtex Style

@conference{icsports14,

author={Rickard Lindstrand and Jeremy Peter and Christian Finnsgård},

title={CFD Prediction of the Effect of Appendages and Leeway on the Force Trend of an Olympic Class Laser Dinghy Hull},

booktitle={Proceedings of the 2nd International Congress on Sports Sciences Research and Technology Support - Volume 1: icSPORTS,},

year={2014},

pages={190-202},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005191101900202},

isbn={978-989-758-057-4},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 2nd International Congress on Sports Sciences Research and Technology Support - Volume 1: icSPORTS,

TI - CFD Prediction of the Effect of Appendages and Leeway on the Force Trend of an Olympic Class Laser Dinghy Hull

SN - 978-989-758-057-4

AU - Lindstrand R.

AU - Peter J.

AU - Finnsgård C.

PY - 2014

SP - 190

EP - 202

DO - 10.5220/0005191101900202