超声空化在船舶与海洋工程中的应用

Biofouling on ships and offshore structures has always been a difficult problem to solve,which not only jeopardizes the structural strength but also brings great economic losses.Ultrasonic cavitation is expected to solve this problem due to its characteristics of no damage to structures and no pollution.Starting from the phenomenon and mechanism of ultrasonic cleaning,this paper introduces the application of ultrasonic cavitation in ship,pipeline and oil cleaning as well as ballast water treatment.By reviewing the existing studies,limitations such as insufficient ultrasonic parameter studies,lack of uniform cleanliness standards,and insufficient cavitation studies are summarized to provide traceable research ideas for improving ultrasonic cavitation technology and to guide the expansion and improvement of its applications.

Numerical techniques for coupling hydrodynamic problems in ship and ocean engineering

Most hydrodynamic problems in ship and ocean engineering are complex and highly coupled.Under the trend of intelligent and digital design for ships and ocean engineering structures,comprehensive performance evaluation and optimization are of vital importance during design.In this process,various coupling effects need to be accurately predicted.With the significant progress of computational fluid dynamics(CFD),many advanced numerical models were proposed to simulate the complex coupling hydrodynamic problems in ship and ocean engineering field.In this paper,five key coupling hydrodynamic problems are introduced,which are hull-propeller-rudder coupling,wave-floating structure coupling,aerodynamic-hydrodynamic coupling,fluid structure coupling and fluid-noise coupling,respectively.The paper focuses on the numerical simulation techniques corresponding to each coupling problem,including the theories and the applications.Future directions and conclusions are provided finally.

CFD技术在船舶与海洋工程复杂粘性流动中的应用进展

Complex flow around floating structures is a highly nonlinear problem,and it is a typical feature in ship and ocean engineering.Traditional experimental methods and potential flow theory have limitations in predicting complex viscous flows.With the improvement of high-performance computing and the development of numerical techniques,computational fluid dynamics(CFD)has become increasingly powerful in predicting the complex viscous flow around floating structures.This paper reviews the recent progress in CFD techniques for numerical solutions of typical complex viscous flows in ship and ocean engineering.Applications to free-surface flows,breaking bow waves of high-speed ship,ship hull-propeller-rudder interaction,vortexinduced vibration of risers,vortex-induced motions of deep-draft platforms,and floating offshore wind turbines are discussed.Typical techniques,including volume of fluid for sharp interface,dynamic overset grid,detached eddy simulation,and fluid-structure coupling,are reviewed along with their applications.Some novel techniques,such as high-efficiency Cartesian grid method and GPU acceleration technique,are discussed in the last part as the future perspective for further enhancement of accuracy and efficiency for CFD simulations of complex flow in ship and ocean engineering.

An Analysis on Application and Trend of Low-Alloy Steel in Shipbuilding and Offshore Engineering Industry

Since 2003,China shipbuilding industry has stepped into the orbit of fast growth.In this paper,a brief analysis has been made on application of low-alloy steel in the shipbuilding and offshore engineering industry,and the further requirements on the marine steel plates elaborated in combination with the future development trend in this industry.Meanwhile,a reference approach is proposed for potential cooperation between the shipbuilding industry and steel industry.

Study on Product Lifecycle Dynamic Information Modeling and Its Application

The PLDIM (Product Lifecycle Dynamic Information Model) is the most important part of the PLDM (Product Lifecycle Dynamic Model ) and it is the basis to create the information system and to implement PLM (Product Lifecycle Management). The information classification, the relationships among all information items, PLDIM mathematic expression, information coding and the 3D synthetic description of the PLDIM are presented. The information flow and information system structure based on the two information centers and Internet/Intranet are proposed, and how to implement this system for ship diesel engines are also introduced according to the PLDIM and PLM solutions.