High-speed Mixed-flow Pump Inlet Duct Optimization And The Research Of Propulsion Performance

Water jet propulsion is different from traditional propeller propulsion mode. It iswidely used in high performance ships due to flexible maneuverability, effective propulsiveefficiency, stronger cavitation resistance,smaller appendage resistance and so on.It’s based on Water jet propulsion model, design and optimization of inlet duct, use CFDsoftware FLUENT to numerical simulation of the new inlet duct,and calculate the flowfield and propulsion performance in the water jet propulsion system.This paper has completed the Water jet propulsion inlet duct design and optimization.Based on odd inlet duct, by changing the inlet duct angle、lip radius and shapes, radius oframp、intake shapes,four aspects to optimize design of inlet duct. By adjusting inlet ductangle α=20°, α=22°, α=24°, α=25°, α=26°, α=28°, α=30°, α=32°, and α=35°nine schemes to optimize inlet duct,to choose the best angle;by adjusting lip radius and lipshapes to optimize inlet duct,adjustment arc radius of lip Angle and parabolic lip Angle of0mm,1mm,3mm,10mm,20mm,30mm,40mm,50mm15schemes to optimize lips,after the results of numerical simulation and analysis, choose best lip radius and lipshape;by Adjusting the radius ramp800mm,900mm,950mm,1000mm,1050mm,1100mm,1200mm,7schemes to design and optimize inlet duct; by Adjusting the shapes of inletintake,4schemes to design and optimize inlet duct. Various schemes are determined,three-dimensional models are set up to numerical calculation, through the analysis of theefficiency of inlet duct, the weighted average, flow uniformity, velocity contours,stagnation point position to superior performance and ensure that the minimum pressure isgreater than the critical value of cavitation, thus optimizing best performance inlet duct.This paper completed the calculation of flow field and propulsion performance of waterjet propulsion system. Under different rotation speeds of3300r/min，3800r/min，4300r/min，5300r/min，5800r/min，6300r/min,different ship speeds of static water,10knot, knot, knot,25,30knot,35knot, knot,40,45knot,1313kinds of working conditions to carry on thenumerical simulation,analysis of blade pressure distribution, propulsion performance curve,optimizing best working condition point.In this paper, Water jet propulsion of inlet duct had designed optimization, to optimizesuperior performance of inlet duct and numerical calculation and analysis of water jet propulsion system. It provides a new means of research and development for setting upwater jet propulsion system design.