Experimental Study Of L Type Podded Propulsor In Open Water Conditions

Modern ship is more and more high to the requirement of the propeller,especially special ships,such as cruise,icebreaker,etc.In order to meet the requirements of the ship.Developed a variety of propeller,pod propulsion as a kind of special propeller arise.In recent years,many countries in the world of research institutions and research workers spend a lot of energy and material development of pod propeller research institutions in China also attach great importance to the development of pod propeller’s technologies,but due to the technology blockade and the development time of pod propeller is later in our country,now the study of pod propulsion’s technology behind some the advanced countries.In allusion to pod propulsion’s development,our country first must come up with a set of mature the hydrodynamic performance of the research methods,including open water test of pod propeller,hydrodynamic performance of pod propeller’s real scale estimation and self-propulsion test of pod propeller.our country also has carried on the open water test of pod propeller,but L compact pod propeller’s test is very few,for the pod propeller of the angle between the bracket and the cabin is 60 degree is much less.Direct at domestic research,on the basis of pod propeller open water dynamometer that the lad design independently,the test combined with 3D printing,PIV technology and CFD fluid technology,the open water performance of pod propeller was studied.The article based on the ITTC procedures to design the open water dynamometer of pod propeller and other equipment.Using the contrivable open water dynamometer to conduct L pod propeller’s open water test,the test including straight-flight,oblique towing and dynamic steering pod unit of axial force,lateral force,steering torque and pod propeller are thrust,torque.To analysis of the pod propeller’s flow field characteristic,applying numerical simulation analysis of pod propeller oblique towing state distribution of velocity field and vorticity field and distribution of propeller,applying PIV technology and CFD method to analysis the flow field characteristics of three sections-the back of blade,side of strut and behind the pod.This article focuses on the same into the coefficient,the different Angle of oblique towing condition of pod propeller hydrodynamic performance comparison,analysis and comparison the same steering rate,advance coefficient under different pod propeller hydrodynamic performance.Based on the analysis of oblique towing status as well as the hydrodynamic performance of steering,they compare different oblique towing direction as well as the hydrodynamic performance of steering direction.To flow field features,PIV measurement system measuring direct flights,oblique towing and so on the different cross section flow field information and comparing with the results of numerical calculation.In view of the existing L type POD propeller,the improvement scheme is proposed and the relative numerical calculation is carried out.