PIV measurements of a fast ship's diffuser stern

The diffuser stern is part of a design concept from Damen and the TU delft: the interceptor diffuser. This concept aims to improve the seakeeping behavior of fast ships in waves. With PIV measurements, a contribution to the development of the diffuser stern is made. The flow acceleration and detachment are studied, and a comparison with a CFD...

Hardware in the Loop Emulation of Ship Propulsion Systems at Model Scale

Requirements on ships are rapidly increasing. In particular, safety and environmental impact are under increasing scrutiny. At the same time, cost and profitability remain as important as they have ever been. These increasingly stringent constraints are beginning to pose problems during the design process. For example, the energy efficiency...

Hardware in the loop experiments with ship propulsion systems in the towing tank: Scale effects, corrections and demonstration

Standards for environmental impact, safety and operational performance of ships are becoming increasingly strict. In order to meet these standards, the performance of new ship designs must be predicted with an increasing level of detail and confidence. As present prediction methods lack realistic, dynamic behaviour of the ship's propulsion plant...

Keel-Rudder Interaction: A look into the wake of a sailing yacht

In the early 00 of this century, Keuning et al. (2007) looked into the hydrodynamic forces on the rudder and the influence of the hull and keel on these forces. Among others, they have assessed the lift and drag forces on the rudder. One of the outcomes of this study was an asymmetric lift curve; for negative rudder angles the rudder seems to...

Research on lift-carry-over in hull-keel-centre board configurations, to improve the performance prediction of sailing yachts at Dykstra Naval Architects

Dykstra Naval Architects are regularly designing large classic sailing yachts or motor-sailors, of which the draft is an important design restriction.The sailing performance is increased by adding lift-generating appendages,without increasing the draft. An example is a retractable centre board, havinga big influence on the sailing properties....

Propeller-engine interaction in a dynamic model scale environment

Regulatory demands on ship designs, such as emission and manoeuvrability requirements, are becoming increasingly stringent, raising the need for advanced methods to predict and assess dynamic propulsion plant behaviour of a new design. At present, model scale experiments and numerical simulations are not able to predict this behaviour in full...

A new generation of sloshing pressure sensors

Sloshing impacts are highly dynamic and localized events. One problem in the measurement of sloshing impact pressures is the limited spatial resolution that can be achieved with current sensors. To overcome this hurdle a project was started to develop new sensors that allow to increase the spatial resolution of pressure measurements by a factor...

Hydrodynamics of Wind-Assisted Ships: A Numerical and Experimental Study on a Systematic Series of Bare Hull Models at Drift Angles

With fuel oil the main driver for operational expenses, increasingly stringent regulations on emissions of ships and a growing environmental awareness throughout the industry, the concept of Wind-Assisted Ship Propulsion (WASP) presents itself as a means to reduce fuel consumption. Though a promising concept, the performance prediction of a wind...

Internal Load Measurement On High Speed Ship Models

For over a century, model tests have supported in ship and offshore structures design. Experimental results can be used to (1) validate theory to apply numerical simulations in the design and (2) for design by testing, directly using the (scaled) results in the design. Recently, at the Ship Hydromechanics and Structures lab of the TU Delft, a...

Status of Wake Vortex Alleviation in the Framework of European Collaboration: Validation Using Tests and CFD Results

This document provides a synthesis of recent research studies that have been conducted in the last decade within several European projects from the 5th and 6th Framework Programmes. All these studies aimed at a better characterization of aircraft wake vortices and then at their subsequent control. In the latter case, the goal is to minimize the...

Mean-Flow Measurements in the Boundary Layer and Wake of a Series 60 C_B = .6 Model Ship with and without Propeller

Results are presented from a towing-tank experiment of propeller-hull interaction conducted in order to provide detailed documentation of the complete flow field appropriate both for explicating the flow physics and validating computational methods. Mean-velocity and pressure field measurements were made for the with- and without-propeller...

The Phenomenon Planing