The parameterisation of turbulence in the marine environment

Hardisty, Jack; Jennings, Ross

Abstract

There are many problems in the fields of flow modelling around structures and tidal stream energy yield analysis which require a thorough understanding of the turbulent and time-averaged flow speeds in marine environments. In this paper we examine the relationship between the turbulence intensity and mean tidal flow speed at a potential tidal stream power site. We report data from the Humber Estuary wherein an Acoustic Doppler Current Profiler were used to capture vertical profiles of the high frequency and mean tidal flow speeds throughout Spring and Neap, Flood and Ebb cycles. We show not only that our results extend earlier work but also suggest that the turbulence intensity, IT, can be described parametrically in terms of the mean flow, U, by an inverse power function IT = α Uᵖ where the coefficient appears to be dependent upon the anisotropic nature of the turbulence. For the data reported here, the coefficient has value of about 17–18 and the exponent lies between −0.6 and −1.0. Confirmation of this relationship should not only improve engineering design work and energy yield analyses in turbulent tidal flows but also be applicable to other problems such as the prediction of sediment mass transport and pollution dispersal in estuarine management studies.

Citation

Hardisty, J., & Jennings, R. (2017). The parameterisation of turbulence in the marine environment. Journal of Marine Engineering and Technology, 16(3), 114-120. https://doi.org/10.1080/20464177.2016.1260892

• Acceptance Date: Nov 11, 2016
• Online Publication Date: Dec 14, 2016
• Publication Date: Sep 2, 2017
• Deposit Date: Mar 6, 2017
• Publicly Available Date: Dec 15, 2017
• Journal: Journal of marine engineering and technology
• Print ISSN: 2046-4177
• Publisher: Routledge
• Peer Reviewed: Peer Reviewed
• Volume: 16
• Issue: 3
• Pages: 114-120
• DOI: https://doi.org/10.1080/20464177.2016.1260892
• Keywords: Tides; Tidal flows; Turbulence intensity; Turbulence strength
• Public URL: https://hull-repository.worktribe.com/output/449180
• Publisher URL: http://www.tandfonline.com/doi/full/10.1080/20464177.2016.1260892
• Additional Information: This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of marine engineering and technology on 14/12/2016, available online: http://www.tandfonline.com/doi/full/10.1080/20464177.2016.1260892
• Contract Date: Mar 6, 2017