Vol. 4 No. 2 Suppl. 1 (2020) - About Water: Novel Technologies for the New Millennium
Special Issue Article

Prevention of Cavitation in Propellers

Mojtaba Taseidifar
School of Science, UNSW Canberra, Northcott Drive, Canberra, ACT 2610, Australia
John Joseph Antony
Dynamikx Pty Ltd, 169 Hampton Road, South Fremantle, WA, Australia
Richard Pashley
School of Science, UNSW Canberra, Northcott Drive, Canberra, ACT 2610, Australia
Bio
De-gassed water flowing directly onto a rotating propeller blade prevents cavitation

Published 2021-03-22

Keywords

  • Cavitation,
  • degassing,
  • hollow fibre membrane,
  • propeller

How to Cite

Taseidifar , M., Antony, J. J., & Pashley, R. (2021). Prevention of Cavitation in Propellers. Substantia, 109-117. https://doi.org/10.36253/Substantia-821

Abstract

It is well known that cavitation phenomena affect the efficiency of propellers. It is a major world wide economic problem for the transport industry. The speed of fast, ocean going vessels is liimted by cavitation effects on hydrofoils and propulsion systems. The main approaches of industry to mitigate the detrimental effects of cavitation on propellers is restricted to varying operating conditions, geometric design and choice of wear resistant materials. We here develop a simple solution to the problem. It has been known for over a century that dissolved gases reduce the tensile strength of liquids by orders of magnitude. De-gassing of a iquid dramatically reduces the ability of a fluid to cavitate.  Propeller cavitation in ships and submarines is typically controlled by reducing rotation rate and/or blade pitch. We here demonstrate the astonishing fact that cavitation can be completely prevented by releasing de-gassed water adjacent to the low pressure side of a rotating propeller, without varying blade speed or pitch. Practical implementation is simple and cheap.

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