On transom clearance
Artikel i vetenskaplig tidskrift, 2015

This paper deals with transom stern flow phenomena around the Froude number where the transom clears the water. Experimental and numerical results for a high-speed hull exhibit a pronounced peak in the resistance coefficient at the clearance speed. This is associated with a maximum in the non- dimensional transom submergence, a minimum in the pressure coefficient at the transom edge and a maximum in the curvature of the flow leaving the edge. Just before clearance, the sum of the hydrodynamic and hydrostatic pressures on the transom yields a force pointing forwards, thereby reducing resistance. This pushing force diminishes abruptly as the transom becomes dry. The total pressure resistance of the rest of the hull increases rapidly just before clearance, mostly due to the increase in hydrostatic pressure resistance, caused by the sudden increase in aft draft. It is the rapid loss of the transom pushing force, together with the rapid increase in pressure resistance of the rest of the hull just before clearance that creates the peak in the total resistance coefficient.

Numerical simulation

Resistance coefficient

Transom clearance

Critical Froude number

Towing tank

Författare

Arash Eslamdoost

Chalmers, Sjöfart och marin teknik, Marin teknik

Lars Larsson

Chalmers, Sjöfart och marin teknik, Marin teknik

Rickard Bensow

Chalmers, Sjöfart och marin teknik, Marin teknik

Ocean Engineering

0029-8018 (ISSN)

Vol. 99 55-62

Styrkeområden

Transport

Energi

Ämneskategorier

Energiteknik

Strömningsmekanik och akustik

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.1016/j.oceaneng.2015.02.008