Fuel efficiency is an important factor for the shipping industry both regarding new build vessels and existing vessels. A method to reduce the fuel consumption of existing vessels operating in off design conditions is to trim a vessel in the most optimum trim condition. The current approach to determine the most efficient trim condition is to perform propulsion tests under different trim condit...

Abstract The main function of the fin stabilizer on patrol boats is anti-rolling and providing comfort for ship personnel. However, installation has a consequence in form appendage resistance ship. This study analyzes magnitude due to NACA 0010 mounted 60m boat at an angle 0º. Reduction expected improve performance which then can optimize use fuels minimize pollution. In early stages, bare hull...

Active illumination underwater brings the backscatter problem. The traditional pulsed laser range-gated imaging (PLRGI) system uses a small gate width to suppress most of backscattered light. As result, depth field (DOF) PLRGI is small. In addition, DOF has be extended when used for searching target. There are several methods extend DOF. However, every method its shortcoming. To overcome these ...

Large water tanks known as towing tanks, wave basins and cavitation tunnels, are used to determine the performance of ships, boats submarines at model-scale. They may also be for noise measurements but suffer from effects reverberation, which makes it difficult capture free field conditions necessary complete characterisation noise. This paper describes an adapted Image Source Model its use und...

The crashworthiness of helicopter fuel tank is vital to the survivability of the passengers and structures. In order to understand and improve the crashworthiness of the soft fuel tank of helicopter during the crash, this paper investigated the dynamic behavior of the nylon woven fabric composite fuel tank striking on the ground. A fluid-structure interaction finite element model of the fuel ta...

Weighted sled towing is a common resisted sprint training technique even though relatively little is known about the effects that such practice has on sprint kinematics. The purpose of this study was to explore the effects of sled towing on acceleration sprint kinematics in field-sport athletes. Twenty men completed a series of sprints without resistance and with loads equating to 12.6 and 32.2...

Complete nonlinear dynamic manoeuvering models of ships, with numerical values, are hard to find in the literature. This paper presents a modeling, identification, and control design where the objective is to manoeuver a ship along desired paths at different velocities. Material from a variety of references have been used to describe the ship model, its difficulties, limitations, and possible s...

This paper discusses the design of hydrodynamically scaled models of offshore structures subjected to wave loading. A considerable amount of engineering design and analysis is required to ensure the high performance of a model/dynamometer system, especially when dealing with large scale models (for example, 1:40). The system is designed to be as rigid as possible so that the dynamometer measure...

An excessive load in resisted sprint training can produce changes in running patterns. Therefore, load control is essential to ensure the specificity of these training methods. The most common way to control it is through the percentage of velocity lost in relation to maximum velocity. The present paper describes a study that aimed to establish the load for sprint training with sled towing. The...