水下航行体湍流数值模拟方法研究进展综述

In this paper,we present an overview of numerical simulation methods for the flow around typical underwater vehicles at high Reynolds numbers,which highlights the dominant flow structures in different regions of interest.This overview covers the forebody,midbody,stern,wake region,and appendages and summarizes flow phenomena,including laminar-to-turbulent transition,turbulent boundary layers,flow under the influence of curvatures,wake interactions,and all associated complex vortex structures.Furthermore,the current issues and challenges of capturing these flow structures are addressed.This overview provides a deep insight into the use of numerical simulation methods,including the Reynolds-averaged Navier–Stokes(RANS)method,large eddy simulation(LES)method,and the hybrid RANS/LES method,and evaluates their applicability in capturing detailed flow features.

Overview of Moving Particle Semi-implicit Techniques for Hydrodynamic Problems in Ocean Engineering

With the significant development of computer hardware,many advanced numerical techniques have been proposed to investigate complex hydrodynamic problems.This article aims to provide a detailed review of moving particle semi-implicit(MPS)techniques and their application in ocean and coastal engineering.The achievements of the MPS method in stability and accuracy,boundary conditions,and acceleration techniques are discussed.The applications of the MPS method,which are classified into two main categories,namely,multiphase flows and fluid-structure interactions,are introduced.Finally,the prospects and conclusions are highlighted.The MPS method has the potential to solve practical problems.

Analysis on Severe Convection Process in Shunde during May 10-11,2020

Using meteorological observation data,Doppler radar,and NCEP 0.25°×0.25°of 6 h reanalysis data,comparative analysis of circulation background,trigger conditions,physical quantity characteristics,and radar image characteristics of two severe convection weather processes in Shunde District during May 10-11,2020 was conducted,and similarities and differences of severe convection processes were explored.The results showed that the two severe convection processes occurred in the situation that there lacked high-altitude trough moving eastward,but low altitude was accompanied by shear line,which was triggered under conditional thermal instability.Vertical velocity profile displayed that severe convection was accompanied by strong convergence and upward movement,and K index and water vapor flux divergence had good corresponding relationship with the occurrence and extinction of severe convection weather in time.The occurrence of strong wind area had certain indicative significance for the prediction of severe convection weather.