A study of transom-stern ventilation

We describe here an extensive set of experiments on a series of five simplified transom-stern ship models. The local wave elevation was measured using surface transducers on the two sides of the model at the transom, as well as at the center of the transom. This data has been analyzed and a new regression formula for the progressive ventilation of the transom, as a function of the transom-draft Froude number has been developed. These formulas take into account both the transom beam-to-draft ratio and the transom-draft Reynolds number. There is now strong evidence that the transom-draft Reynolds number plays a much lesser rôle in this phenomenon than previously thought. Using these new formulas, one can now predict the resistance components with greater confidence. Hence, the resistance of a high-speed vessel with a transom stern can be estimated accurately over the entire speed range. © 2007 - IOS Press and the authors. All rights reserved.