Faculty Member

Environmental Systems

Research Group Coastal and Ocean Engineering
Staff
Professor:
Motohiko UMEYAMA

Associate Professor:
Tetsuya SHINTANI

Research Interests

Our research interests include nonlinear wave theories, internal waves, sediment-laden flow, and turbulence in wave and current fields. We are particularly interested in the behavior of the Eulerian-mean flow change due to interaction between waves and a current.

  • PIV measurements for rear-end and head-on collisions of solitary waves
  • Mean velocity changes due to interaction between bichromatic waves and a current
  • Changes in turbulent flow structure under combined wave-current motions
  • PIV and PTV measurements of particle velocities and trajectories for Stokes waves following a steady current
  • Partial standing waves due to a wave and current interaction and the amount of irregular-wave overtopping at a seawall
  • PIV techniques for velocity fields of internal waves over a slowly varying bottom topography
  • Particle image velocimetry measurements for Stokes progressive internal waves
  • Shore protection to accelerative sea level rise and hypothetical tropical cyclone under El Nino weather pattern in small island states
  • Floating cities as a solution to the escalating sea level rise in lower-lying land areas
  • Study of saline water intrusion in Red River, Vietnam
  • Study of water movement and quality in Ha Long Bay,Vietnam

Titles of master theses and doctoral dissertations

2015
  1. Experimental studies on rear-end and head-on collisions of two unequal solitary waves and interactions of a single solitary wave with a current using PIV.
  2. Theoretical and experimental analyses of roll-wave overtopping on a vertical wall using numerical model with PLIC (Picewise Linear Interface Calculation) and VOF (Volume of Fluid) methods.
2014
  1. Numerical analysis on sediment transport mechanism near Hai Phong Port using the Coupled Ocean-Atmosphere-Wave-Sediment Transport Modeling System.
  2. Kinematical investigation of rear-end and head-on collisions of two unequal solitary waves using PIV.
2013
  1. * Visualization and numerical analyses for mass transport due to internal waves propagating in a diffusive transition layer of the density-stratified water.
  2. * Influence of changes in topography, tides and freshwater discharge on salinity distribution in a deltaic estuarine system.

*: Doctoral dissertation

Titles of bachelor theses

2015
  1. Measurement of wave and current co-existing velocity field using PIV and study of physical aspects for a single solitary wave using some tiny pressure transducers.
  2. Experimental study on wave overtopping rate during Stokes-wave attack using electro-magnetic current meter on the top of vertical structure.
  3. On dynamic pressure distribution under Stokes waves just before wave breaking.
  4. Stability of floating structure and optimization design method of unite modules.
2014
  1. Changes in Eulerian-mean velocity under combined wave-current motions.
  2. Experimental investigation on phase shifts after head-on collisions of two solitary waves with different amplitudes in a long wave tank.
2013
  1. Development of numerical model based on the SPH method and application of wave overtopping problem for solitary waves.
  2. Super-resolution PIV measurements for rear-end and head-on collisions of two solitary waves.
  3. Two dimensional numerical investigation of solitary-like tsunami wave interactions using VOF.