Hydrodynamics and Mass Transfer on a Moving Drop of Water
The fluid dynamics and mass transfer associated with moving water drops are examined. In the first part, numerical solution of the transient hydrodynamics around and inside a drop falling...
Properties of Small-Scale Waves in Sheared Gas-Liquid Flows
Small wind-generated waves are examined theoretically and experimentally in a small laboratory flow system, at conditions close to neutral stability in an attempt to better characterize...
Surface Renewal Due to Large Flow Structures in Open Channel Flow
It is shown that under certain flow conditions, surface renewal cannot be understood as an exclusive result of the bursting occurring near the wall, as proposed by several authors. Flow...
Turbulent Velocity and Gas Concentration Measurements in the Near-Surface Layer
An experiment was undertaken to study the mechanism of interfacial mass transfer. Near-surface liquid turbulence and oxygen concentration fluctuations have been measured in a grid-stirred...
Development of Method for Measuring Near-Surface Turbulence
New techniques for tracking particles in fluid are presented. A method to make micro-capsules which are filled with pure water and covered with a thin film of polystyrene is developed....
Measurement of Reaeration Coefficient with the Soluble Solids Probe
The results of analytical and experimental studies are presented, showing that the proposed method for indirect determination of gas transfer coefficients at gas-liquid interfaces, based...
Gas Transfer at Hydraulic Structures
The objective of this paper is to identify and briefly summarize the state-of-the-art in measuring and describing gas transfer at hydraulic structures. Basic theory of mass transfer at...
Oxygen Transfer in Turbulent Shear Flows
Oxygen transfer equation for the air-water two-phase aeration region of turbulent shear flow in a vertical pipe is derived. Dimensionless variables significant in characterizing the transfer...
Electronic Data Acquisition and Analysis for Soil Dynamics Applications
Recent advances in micro-computer-based data acquisition hardware and software systems have created a window of opportunity for the soil dynamics specialist. Increases in the number of...
Use of Bender Elements in Soil Dynamics Experiments
Transducers employing piezoelectric bender elements have been found to be versatile sources and receivers of small-amplitude shear waves, with multiple potential applications. The constitutive...
Use of Piezoceramic Bender Elements in Soil Dynamics Testing
The use of piezoceramic bender elements is described to measure small strain, shear wave velocity distributions in soil models used in centrifuge and shake table testing. Experimental...
San Francisco Double-Deck Viaduct Retrofits
Following the Loma Prieta Earthquake in October 1989, six double-deck reinforced concrete viaducts in San Francisco were closed because of some isolated damage, and as a precaution for...
A Study of Shield Tunnel's Earthquake Prevention Under a Big Earthquake
Currently, the most commonly used approach for determining the aseismicity of a shield tunnel is the 'Response Displacement Method.' This is based on analysed...
Earthquake Response of Liquid-Filled Pipeline at Finite Depth Below Ground Surface
This paper deals with the problem of earthquake response analysis of pipelines, empty or fully filled with liquid and buried at a finite depth below the ground surface. Emphasis is placed...
Effects of Cracking on Damping of Concrete Dams
A methodology is presented for dynamic analysis of concrete dams that considers the nonlinear stiffness and energy absorption effects of cracking. A cracking-consistent damping model is...
A Dynamic Modelling Framework of Real-Time Guidance Systems in General Urban Traffic Networks
There is considerable interest around the world in developing and implementing realtime driver information and/or guidance systems to reduce congestion in the urban traffic networks. However...
Dynamic Stochastic Equilibrium Model in Multiple Vehicle Type Transportation Networks
In this study, a multi-vehicle type dynamic stochastic user equilibrium model (called MDSUE model for abbreviation) is developed. By using MDSUE model, the prediction of departure rates...
Effectiveness of Real-Time Information Strategies in Situations of Non-Recurrent Congestion
The effect of real-time information on the performance of a traffic commuting corridor in situations of non-recurrent congestion is studied using a dynamic simulation model. Non-recurrent...
Observation and Modeling of Mobile Environment
Perception of the environment in a mobile robot is a difficult task. Other moving objects and various changes in the environment and motion of the robot must be handled together. Control...
The Effects of Runway Roughness on Aircraft Fatigue Life
A computer code developed within the Flight Dynamics Directorate of the Wright Laboratory was used to simulate the dynamic response of heavy aircraft operating on runways with various...
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