Towing Tank Model Tests for Propulsive Performance Analysis of a Waterjet-Propelled Amphibious Vehicle

Abstract

The present study aims to examine the resistance and propulsion performance of an amphibious vehicle with waterjet propulsion by conducting a series of towing tank model tests. The test model was an armored vehicle consisted of a box-shaped chassis, two flush-type waterjets, a bow flap, and a trimtab. Following the powering prediction procedure of a conventional ship, the resistance test, waterjet system and bollard pull test, and self-propulsion test were performed. The Froude number based on the characteristic length and advance speed for the model test ranged from 0.883 to 1.275. The effect of the track deployment conditions was also investigated by conducting a test with the retracted and normal track condition. In the bollard pull and self-propulsion test where two waterjets were installed onto the chassis, the flow rate of the waterjet was higher than that in the single waterjet system test, resulting in high thrust. The propulsive efficiency increased in high advance speeds as the transom was exposed to air.