Effective use of the transport efficiency concept

This DLBA paper helps to apply the powerful tool of transport efficiency, expanding upon the information presented in the paper titled “Achievements with Advanced Craft”. Using this calculation technique, DLBA developed a tool that can quickly evaluate the performance of a specific boat, and accurately predict vessel performance based on minimal information. Today, the tool is proving very beneficial in sanity checking results of Computational Fluid Dynamics (CFD) resistance predictions for our clients.

“We constantly update the state-of-the-art curves using full scale sea trial data where weight is documented, speed is captured via GPS as an average of two directions, and shaft power is measured. If you think you have a vessel with performance that could redefine the state-of-the-art – we’d love to talk to you about it,” says DLBA’s Jeffrey Bowles.

The purpose of this presentation is to explain the effective use of transport efficiency for evaluating existing or new concepts. The concept of transport efficiency has been proposed and published by Blount (1994) and state-of-the-art calm water curves have been developed. These curves are an effective and easily manipulated macroscopic tool for quickly evaluating existing or new concepts in calm water. The utility of the curves will be demonstrated through the evaluation of the feasibility of a 100 knot yacht. In addition, concepts provided from the audience will be quickly and easily examined.

While transport efficiency answers the question “how fast is it?” useful load fraction will be presented to answer the question “how much can it carry?” Useful load fraction will be covered briefly to present a rounded discussion. Finally, a proposal will be presented for developing rough water transport efficiency curves. Currently, these curves have not been developed; however, as sea state increases, various hull and propulsion technologies will be shown to be optimal in terms of transport efficiency.

In case you would like to receive the full paper or discuss about this subject, please contact Jeffrey Bowles.