Análise de Comportamento no Mar para um Navio Escolta Modular Empregando sua Rampa de Popa.

Abstract

The use of organic vessels deployment systems by stern ramp has replaced the traditional launch/recovery methods by lateral davits on escort ships in several navies. However, there are limitations of studies that investigate the influence of wave induced loads and motions of ships that use this resource, thus hindering ideal ramp designs. Therefore, the present study aims to identify the main seakeeping changes suffered by an escort ship when it uses its stern ramp during operations involving launch/recovery of organic vehicles. For this, a comparative seakeeping analysis was carried out considering the conditions of a ship operating and not operating the ramp. The study was carried out assuming the hull with zero speed, and the analysis was carried out for seven wave incidences. Results showed that variations in the ship motion response, resulting from the use of the ramp, were motivated by disturbances suffered at the terms of additional mass and damping, and that is recommended operating the ramp during following seas. Therefore, the approach used in this dissertation shows great significance of the influence of the hydrodynamic coefficients in the seakeeping of this type of ship and in the selection of its ideal heading to operate with the stern ramp.