How Tion Puay

Universiti Sains Malaysia | USM · River Engineering and Drainage Research Centre (REDAC)

This paper describes a self-similarity-analysis-based inundation process in which the water depth at the inlet increases as a power function of time. Numerical analyses of the inundation process are conducted to evaluate the feasibility and stability of two types of regimes: inertia-pressure regime and pressure-friction regime. Numerical simulation...

The tsunami is one of the deadliest natural disasters, responsible for more than 260,000 deaths and billions in economic losses over the last two decades. The footage of the devastating power of the 2004 Indian Ocean tsunami perhaps remains vivid in the memory of most survivors, and Malaysia was one of the countries affected by the unprecedented 20...

To design a hydraulic structure such as gravity dam, it is crucial to predict the. Location and the length of the hydraulic jump. Numerical model comes in handy to deal with the conditions which are costly to reproduce the laboratories such as the hydraulic jump experiment. In this study, two models (Saint-Venant model and Boussinesq model) are sol...

Savonius turbines for wind and hydrokinetic applications both operate on the same principle in terms of power generation. However, the effects of their power performance when augmented with various deflector configurations in wind and water have not been comprehensively investigated, and the comparative analysis in the literature still lacks due to...

This study is motivated by the need to mitigate damages caused by mudflow disaster, which is occurring frequently due to intensive forest clearing and uncontrolled land use at highland. Numerical modelling of mudflow is challenging as the propagation speed and rheological behavior of the flow relies on the accuracy of the numerical scheme and choic...

Numerous efforts have been made to estimate the tsunami wave loads on structures, particularly box-shaped buildings (flat-roofed). As buildings have different types of roofs, insights into their respective wave flow mechanisms are important especially for the overtopping case. This study, therefore, focuses on the effect of roof types on tsunami-li...

This study presents the decays of three components of velocity for a ship twin-propeller jet associated with turbulence intensities using the Acoustic Doppler Velocimetry (ADV) measurement and computational fluid dynamics (CFD) methods. Previous research has shown that a single-propeller jet consists of a zone of flow establishment and a zone of es...

This study presents the development, refinement, and application of a 3-D multiphase flow model for the simulation of tsunami propagation on land and its hydrodynamic force on a coastal building. The model is based on the Volume/Surface Integrated Average-based Multi-Moment Method (VSIAM3) with improved accuracy by adopting the temporary moment (TM...

Tsunamis are destructive waves that contain a series of long period waves. The enormous force of tsunami waves on coastal infrastructures has been evidentially demonstrated by the 2004 Indian Ocean tsunami. As the variability of tsunami-induced force is based on a site-specific basis, an insight into the flow characteristics of tsunami waves is imp...

Previous studies demonstrated an introduction of building opening could decrease the tsunami loads on the external wall. However, tsunami waves flowing through the building opening could induce loads on the interior part. This study presented an experimental investigation of tsunami flow through a real building with opening. Three nominal wave cond...

In this paper, we applied and evaluated the performance of a higher-order scheme based on volume/surface integrated average based multi-moment method (VSIAM3) for the simulation of tsunami propagation on land. The advection term in the momentum equation was solved by using the conservative semi-Lagrangian scheme with third-order accuracy based on c...

The flow of water can be modeled by either single phase flow or multiphase flow approach. Despite having the advantage of avoiding discontinuity at the free surface normally faced in single phase model, the multiphase model is still facing the difficulty to advect the sharp interface between two fluids. This study attempts to validate a multiphase...

The interest in the numerical simulation of free surface flows is increasing due to the rapid development of computer technology. A two-dimensional numerical model based on the Marker and Cell (MAC) method is developed in this study. In the current development, the advection term in the Navier-Stokes equation is solved using the third-order Quadrat...

In the design of hydraulic structures, it is common to deal with the supercritical flow. Abrupt expansion structure represents a type of transition often constructed in manmade hydraulic structure (e.g. chutes in dam structures, sewer or drainage system, an irrigation channel, etc.) to cater the geometry difference. It is important to cater to the...

Due to rapid urbanization, surface water drainage systems are designed to perform as natural drainage acting as water storage areas that allow infiltration and evaporation and to solve issues caused by traditional drainage system As there is an increase of attention on Sustainable Urban Drainage system (SuDs) to manage storm water, a simple yet eff...

When dealing with the design of a hydraulic structure, lateral expansion is often necessary for flow emerging at high velocity served as a cross-sectional transition. If the abrupt expansion structure is made to diverge rapidly, it will cause the major part of the flow fail to follow the boundaries. If the transition is too gradual, it will result...

Sustainable Urban Drainage System (SuDS) such as swales and rain gardens is showing growing popularity as a green technology for stormwater management and it can be used in all types of development to provide a natural approach to managing drainage. Soil permeability is a critical factor in selecting the right SuDS technique for a site. On this bas...

Sustainable Urban Drainage System (SUDS) such as swales and rain gardens is showing growing popularity as green technology for stormwater management. Permeability and flow characteristic in porous material are critical factors when designing SUDS facilities. In this study a two-dimensional numerical simulation using Marker and Cell (MAC) method is...

Alluvial rivers are self-regulating in the sense that they adjust their characteristics in response to any change in the environment. These environmental changes may occur naturally, such as climatic variation, major floodings, human activities including damming, diversion, sand and gravel mining, channelization, bank protection, and bridge constru...

This study presents a mathematical model for the injection of Bingham fluid as common grout material into a horizontal slot formed between parallel plates. The proposed model consisted of a grout reservoir model, a slot model, and an intermediate model that bridged the former two models. The authors showed that it is necessary to include a grout re...

The study aims to investigate the flow characteristics of Newtonian and power-law non Newtonian fluids by using the dam-break of finite extent problem. Analytical and numerical studies are carried out to clarify the flow characteristics. In the analytical study, shallow flow equations are used to derive the characteristic in the viscous flow region...

Engineered soil media plays significant role in enhancing bioretention performance in terms of water quantity and quality aspects. There was limited research on hydraulic response in establishing design parameters such as soil depths. This paper presents a preliminary study on the evolution of hydraulic conductivity over time and examine the stormw...

The phenomenon of injection into a parallel slot under laminar flow condition is investigated analytically and numerically in this study. A comprehensive mathematical model capable of simulating the injection phenomenon from the initial stage until late stage is developed. It is shown that a tank model is necessary in order to reproduce the initial...

The paper describes some of the fundamental characteristics of super-critical flow discharged from an abrupt expansion structure. The flow structure near the abrupt expansion is studied by dividing the flow into the inertia-pressure flow region and the shear stress-pressure flow region. The inertia-pressure flow region is a region where the flow is...

In this study, a finite-extent dam-break model is used to reproduce the characteristics of inertial and viscous flow phases of Newtonian fluid by using a mathematical integral model. The governing equations of the flow which are comprised of the depth-averaged continuity, momentum and energy equations are transformed through integration process fro...

In this study, we investigate the characteristics of dam-break flow of low viscosity Bingham fluid by deriving an approximate solution for the time development of the front position and depth at the origin of the flow. The asymptotic solutions representing the characteristic of Bingham fluid in the limit of low plastic viscosity are verified with a...

This paper describes the basic characteristics of the development of supercritical flows in the downstream of an abrupt expansion in a steep open channel. Although Rouse and Bhoot (1951) showed the method of analysis to calculate supercritical flows in the downstream of an abrupt expansion based on Method of Characteristics (MOC) with a graphical m...

This paper describes the basic characteristics of flow invasion generated by tsunamis over a land. Assuming the self-similarity distributions of flow depth and velocity in the shallow flow equations, the basic characteristics of invasion processes such as the front position, the inflow discharge etc., are obtained in connection with the temporal ch...

This paper deals with the study of free surface flow near an abrupt expansion in an open-channel. A three dimensional free-surface numerical model is developed to simulate the phenomenon. The numerical model is based on the Volume of Fluid (VOF) method. Cubic Interpolated Profile (CIP) scheme is used to solve the advection term in the Navier-Stokes...

This paper presents a fundamental study of Bingham fluid by means of dam-break flow model. A numerical model based on a two-dimensional free-surface VOF (Volume of Fluid) method is developed to simulate the slump flow test of fresh concrete and used to verify the characteristic flow phases of Bingham fluid. The advection terms in the Navier-Stokes...

Characteristics of inertia flow generated from the release of inviscid fluid behing a dam with finite extent are examined. Analytical solutions of the whole domain of the flow is derived using a moving coordinate system. Depth and velocity are expressed in a power series with moving coordinate and the coefficient of power series are determined by s...

Characteristics of inertial flow generated from the release of inviscid fluid behind a dam with finite extent in a semi-infinitely long, initially dry channel are examined. Analytical solutions of the flow int he whole domain from the moment the flow is initiated are derived. Comparison with a depth averaged numerical model is carred out.

In this study, the characteristics of inertia and viscous regions of shallow flow are investigated by means of dam break flow with finite volume occurring in a smooth rectangular channel. Inviscid fluid and viscous fluid, comprising of Newtonian and non-Newtonian are studied theoretically and similarity solutions describing both inertia and viscous...

This paper presents an attempt to express the characteristic of inertia region of instantaneous dam break flow with finite volume occurring in a smooth rectangular channel by a simple means of deriving similarity solutions for the temporal variation of depth at the origin, and propagation of the front wave. Verification of the analytical solution i...

Kyoto University (京都大学) 0048 新制・課程博士 博士(工学) 甲第15344号 工博第3223号 新制/工/1485 27822 2010-03-23 京都大学大学院工学研究科都市社会工学専攻 (主査)教授 細田 尚, 教授 後藤 仁志, 准教授 米山 望 学位規則第4条第1項該当