A METHOD TO EVALUATE THE PERFORMANCE OF WATERJET PROPULSORS USING A MODEL SCALE SETUP

Abstract

Waterjet propulsor is a key component in the Small High-Speed Craft (SHSC) industry. Although the SHSC industry is well established in Sri Lanka, no waterjets are designed or manufactured due to the absence of prototype testing facilities in the country. The availability of such facilities provides the opportunity not only for the waterjet designers and manufacturers but also for the shipyards and design offices to evaluate the performance of waterjets when selecting propulsion systems at the preliminary design phase of their craft. Therefore, a method is proposed to test and evaluate the performance of waterjets using a model scale test setup in the early design stage for a Small High-Speed Craft. In this setup, a waterjet mounted on an SHSC- hull is fully submerged and secured in a water tank with a circulation pump loop setup. The waterjet is driven by an electric motor under varying flow conditions and the performance is evaluated using different measures, such as the head, power, torque and efficiency as recommended in the existing methods. This paper presents a method to appropriately scale the entire test setup, select a suitable hull-jet configuration and proposes an approach to evaluate waterjet performance with the aid of existing measures and methods using the proposed model scale test setup.