Hydrodynamics and Transport for Water Quality Modeling

James L. Martin, Steven C. McCutcheon

• Éditeur: CRC Press
• Année: 2018
• ISBN:
  9781351439879
• Édition: 1
• Sujet: Technik & Maschinenbau
• Sous-sujet: Umweltmanagement

Hydrodynamics and Transport for Water Quality Modeling presents a complete overview of current methods used to describe or predict transport in aquatic systems, with special emphasis on water quality modeling. The book features detailed descriptions of each method, supported by sample applications and case studies drawn from the authors' years of experience in the field. Each chapter examines a variety of modeling approaches, from simple to complex. This unique text/reference offers a wealth of information previously unavailable from a single source.The book begins with an overview of basic principles, and an introduction to the measurement and analysis of flow. The following section focuses on rivers and streams, including model complexity and data requirements, methods for estimating mixing, hydrologic routing methods, and unsteady flow modeling. The third section considers lakes and reservoirs, and discusses stratification and temperature modeling, mixing methods, reservoir routing and water balances, and dynamic modeling using one-, two-, and three-dimensional models. The book concludes with a section on estuaries, containing topics such as origins and classification, tides, mixing methods, tidally averaged estuary models, and dynamic modeling. Over 250 figures support the text.This is a valuable guide for students and practicing modelers who do not have extensive backgrounds in fluid dynamics.

Part I

Fundamentals

Part I

Fundamentals

CONTENTS

1

Fundamental Relationships for Flow and Transport

I.	Mechanistic Versus Empirical Modeling
II.	General Principles A. Laws of Conservation B. Extrinsic Versus Intrinsic Properties C. Net Accumulation: Application of the Laws of Conservation D. Control Volumes
III.	Physical Properties of Water A. Density and Specific Weight B. Compressibility C. Newtonian Fluids and Molecular Viscosity D. Molecular Diffusivity
IV.	Instantaneous Equations for Fluid Flow and Transport A. Fundamental Form of the Conservation Equations B. Instantaneous Equation for Continuity of Water C. Instantaneous Equations for the Conservation of Momentum D. Instantaneous Equations for the Conservation of Constituent Mass or Thermal Energy
V.	Reynolds Time-Averaged Mean Flow and Transport Equations A. Turbulent Motion B. Statistical Relationships C. Turbulence Closure
VI.	Model Complexity: Selection and Development A. Model Resolution 1. Scales of Interest 2. Time Variation 3. Spatial Dimensions for Solving the Governing Equations 4. Methods to Simulate the Water Surface 5. Turbulence Parameterization 6. Forcing Functions or Sources and Sinks a. Water Mass b. Momentum c. Constituent Mass B. Solution Techniques 1. Analytical Solutions 2. Numerical Solution Techniques
VII.	Data Requirements A. Boundary Conditions B. Initial Conditions C. Data for Model Application and Evaluation 1. Statistical Tests of Paired Observations and Simulations 2. Sensitivity Analysis 3. Error Analysis D. Data for Evaluation of Environmental Control
VIII.	Definitions
IX.	Dimensionless Numbers

2

Measurement and Analysis of Flow

I.	Introduction
II.	Measurement of Velocity and Flow A. Float Methods B. Current Meters. 1. Mechanical Current Meters 2. Acoustic Current Measurement 3. Electromagnetic Current Measurement 4. Deployment of Current Meters C. Flow Measurement at Control Structures D. Remote Sensing
III.	Measurement of Stage
IV.	Computation of Discharge
V.	Tracer Studies A. Measurement of Fluorescent Dyes B. Properties of Fluorescent Dyes 1. Temperature Effects 2. Background Interference 3. Sorption 4. pH Effects 5. Photodegradation 6. Chemical Reactions and Quenching 7. Density Effects 8. Toxicity C. Types of Dye Studies 1. Instantaneous Release 2. Continuous Release D. Planning Dye Studies 1. Estimating Mean Velocities 2. Mixing Considerations 3. Estimating the Quantity of Dye Releases 4. Determining Locations of Sampling Stations
VI.	Estimating Design Flows A. Design Conditions for Dynamic Flows B. Design Conditions for Steady Flows 1. Extreme-Value-Based Design Flows a. Distribution-Free Method b. Known or Estimated Probability Distribution 2. Biologically Based Design Flows

References

Symbols Used in Part I

Problems

Appendixes

I.A Physical Properties of Water

I.B Unit Conversion Factors

I.C Values of Frequency Factor K for Use in the Log Pearson Type III Distribution for Low-Flow Analyses

I.D Values of Frequency Factor K for Use in the Log Pearson Type III Distribution for High-Flow Analyses

I.E Standard Variant z„ Associated with Typical Return Intervals

1

Fundamental Relationships for Flow and Transport

I. Mechanistic Versus Empirical Modeling

Water flow is a fundamental mechanism that controls a significant amount of the variability of water quality in streams, lakes, and estuaries (McCutcheon 1989). Any fundamental study of water quality, including modeling investigations, requires knowledge of the pathway, volume, and velocity of the water. In practical terms, the first step in any water quality modeling study is to determine “where the water goes” and how water movement affects the concentrations of dissolved and suspended materials. Equally important is the history of water movement, which provides a hint of how to trace contaminants back to various sources. Relating contaminants to sources is an integral part of establishing cause-and-effect relationships between sources of impurities, and the effects on water quality. Establishing what controls water quality is one of the most powerful uses of models, and flow models are important for that reason alone.

To predict water movement and water quality, most modem mathematical models incorporate the underlying mechanisms that cause change. Incorporation o...