Speaker
Description
Modern requirements in shipbuilding and marine engineering necessitate continuous improvement of propulsion systems, with particular emphasis on waterjet propulsors due to their high maneuverability and efficiency at elevated speeds. This study presents a detailed analysis of hydrodynamic reaction forces generated during the interaction of a high-speed water jet with deflector surfaces of varying geometries. The primary objective is to evaluate the efficiency of converting the jet’s kinetic energy into useful mechanical reaction depending on the geometric profile.
The experimental investigation was conducted using a specialized laboratory test stand (HM 150.08), enabling precise measurement and quantitative assessment of momentum change. Four deflector geometries were examined: flat (90° deflection), semi-circular (180°), oblique (45°), and conical (135°). By systematically measuring volumetric flow rate, calculating jet velocity, and recording the balancing force via a lever mechanism, reliable experimental data were obtained and compared with theoretical predictions based on the conservation of momentum.
The results demonstrate that the jet deflection angle plays a critical role in system efficiency. The semi-circular surface (180°) achieves the highest energy utilization by maximizing momentum change with minimal fluid consumption. In contrast, the oblique surface exhibits the lowest efficiency, requiring a significantly higher flow rate to produce the same reaction force. The flat and conical geometries show intermediate performance characteristics.
These findings have direct applications in marine mechatronics, including the mechanical design of waterjet propulsion and reversing systems, as well as the development of control algorithms for electronic control units. Incorporating these hydrodynamic relationships enables improved sensor calibration, compensation for nonlinear effects, and enhanced overall energy efficiency and maneuverability of modern marine vessels.