Comparison between methodologies for calculating global ice load actingon podded propulsion unit

Authors: M.S. Boyko, M.A. Kuteynikov

Abstract

The paper covers the calculation of the maximum global ice load acting on a podded propulsion unit (PPU) installed on the ice-going ship. It is demonstrated that the unified methodology to calculate such loads is not currently available, however, there have been different methodologies published. The article provides a short analysis with respect to the main features relevant to each of the methodologies, giving the review of published papers dedicated to the PPU ice loads measurements for ships in service. The comparison of design ice loads is made based on a number of PPUs with geometrical parameters representing contemporary PPUs installed on ice-going ships. The comparison shows that the application of existing methodologies provides the results that are not completely in agreement with each other. A number of possible ways for continuation of research and harmonization of methodologies are outlined.

Keywords: podded propulsion unit, ice load.

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About authors:

M.S. Boyko - PhD, FAI "Russian Maritime Register of Shipping", St. Petersburg, e-mail: boyko.ms@rs-class.org

M.A. Kuteynikov - DSc, FAI "Russian maritime register of shipping", St. Petersburg, e-mail: kuteynikov.ma@rs-class.org

Issue: 58/59 (2020)

For citation: M.S. Boyko, M.A. Kuteynikov. Comparison between methodologies for calculating global ice load acting on podded propulsion unit. Research Bulletin by Russian Maritime Register of Shipping. 2020, No. 58/59, pp. 50-63.

UDC 629.129.791

Pp: 50-63