Analysis of the use of waterjet propulsion on unmanned surface vehicle models

Waterjet propulsion on the unmanned surface vehicle ships is a propulsion system with a working principle that uses a water spray system as a propelled. The thrust generated depends on the available water. The spray of water in the nozzle are generated from the inlet at the bottom of the ship which is assisted by a pump on the waterjet. In this part of the inlet will affect the distribution of the flow that will pass the pump and finally exit through the nozzle. The purpose of this study is to analyze the inlet-passage on the waterjet which is varied with the inlet velocity ratio to get the maximum efficiency value from the waterjet propulsion system. This study works using the computational fluid dynamics (CFO) method and analytical calculations. Inlet velocity ratio (IVR) is varied from 0.54, 0.59, 0.67, 0.78, 0.94, 1.18, 1.64, and 2.38 which will be compared to the results. From the results of the analysis we will get the volume coming out of the waterjet and the results will get the thrust value. The highest thrust value obtained is based on variations in the IVR value of 2.38, and the maximum efficiency value of 98%.