Prediction of squat for underkeel clearance

This chapter presents a summary of ship squat and its effect on vessel underkeel clearance. An overview of squat research and its importance in safe and efficient design of entrance channels is presented. Representative PIANC empirical formulas for predicting squat in canals and in restricted and open channels are discussed and illustrated with examples. Most of these formulas are based on hard bottoms and single ships. Ongoing research on passing and overtaking ships in confined channels, and offset distances and drift angles is presented. The effect of fluid bottoms or mud is described. Numerical modeling of squat is an area of future research and some comparisons are presented and discussed. © 2018 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.