POWERING PREDICTION FOR SURFACE EFFECT SHIPS BASED ON MODEL RESULTS.

Abstract

A method employing the laws of dynamic similarity to scale experimental model data is presented for predicting the powering performance of large surface effect ships. The data are reduced to individual components, including cushion wavemaking drag, sidewall and appendage frictional and form drags, aerodynamic drag, and seal drag. These components are appropriately scaled by either Froude or Reynolds scaling laws. Water channel and model dimension effects on wavemaking drag are discussed and a technique for calculating sidewall wetted area is presented. An experimentally derived algorithm characterizing seal-induced and frictional drag is explained. Drag predictions are compared with experimental trails data.