Expert Systems for Mixing Zone Analysis and Engineering Design

Robert L. Doneker, PhD., P.E.Assistant ProfessorDepartment of Environmental Science and

EngineeringOGI School of Science & EngineeringOregon Health &Science UniversityPortland, Oregon, USA

Sponsor: USEPA, Office of Science and Technology, Office of Water

Dr. Russ Kinnerson, Project Officer

Mt. Saint Helens makes a powerful demonstration of Mother nature’s

version of a mixing zone.

Overview

A coastal sewage outfall attracts aquatic life. Water quality prediction is essential for environmental protection,

regulatory control, and engineering design.

n Examples Of Mixing Processes

n Regulatory Mixing Zones

n Hydrodynamic Mixing Zone Definitions• Near/Far Field Mixing• Boundary Interaction

n CORMIX Methodologyn Research Needsn CORMIX-GI System

Demonstration

n Examples Of Mixing Processes

n Regulatory Mixing Zones

n Hydrodynamic Mixing Zone Definitions• Near/Far Field Mixing• Boundary Interaction

n CORMIX Methodologyn Research Needsn CORMIX-GI System

Demonstration

Wastewater-Sewage

New Zealand sewage discharge and boundary interaction.

Cooling Waters

Power plant cooling water multiport diffuser discharge into river.

Desalination/Brines

Surface discharge of brine freshwater lake.

Thermal Refugia-Tributary Mixing Zones

Thermal Refugia- Groundwater Mixing Zones

FLIR Image Temperature Scale (*C)

>50 30-50 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 <15

Regulatory Mixing Zones

Regulatory Mixing Zones allow for the initial dilution

of a wastewater.

n May allow for efficient pollutant assimilation

n Water body as a whole must not be impaired

n Special requirements for toxic discharges• CMC values• CCC values

n May occur in Near-field or Far-field

n May allow for efficient pollutant assimilation

n Water body as a whole must not be impaired

n Special requirements for toxic discharges• CMC values• CCC values

n May occur in Near-field or Far-field

Hydrodynamic Mixing

n Discharge Characteristics• Volume, Momentum, &

Buoyancy Fluxn Ambient Characteristics

• Ambient Crossflow• Density Stratification

n Boundary Interaction• Vertical, Lateral, & Near-

Field Attachments• Transition from Near-

Field To Far-field

n Discharge Characteristics• Volume, Momentum, &

Buoyancy Fluxn Ambient Characteristics

• Ambient Crossflow• Density Stratification

n Boundary Interaction• Vertical, Lateral, & Near-

Field Attachments• Transition from Near-

Field To Far-field An example of coastal surface discharge plume in New Zealand.

Near-field Mixing Processes

n Close to dischargen Initial fluxes and

outfall geometry dominate mixing process

n Outfall design has some degree of effect on mixing zone behavior

n Close to dischargen Initial fluxes and

outfall geometry dominate mixing process

n Outfall design has some degree of effect on mixing zone behavior

Illustrative near-field and far-field.

Stable Discharge Conditionsn Strong Buoyancyn Weak Momentumn “Deep Water”

n Strong Buoyancyn Weak Momentumn “Deep Water”

Unstable Discharge Conditionsn Weak Buoyancyn Strong Momentumn “Shallow Water”

n Weak Buoyancyn Strong Momentumn “Shallow Water”

Far-field Mixing Processes

n After boundary interaction

n Ambient conditions dominate mixing process

n Density currents and Passive diffusion are the mixing processes

n After boundary interaction

n Ambient conditions dominate mixing process

n Density currents and Passive diffusion are the mixing processes

A angler hopes to get lucky in a far-field density current .

Basic Discharge Flux Quantities

n Volume Flux• Q0=u0a0

n Momentum Flux• M0=u0Qo

n Buoyancy Flux• J0=g’0Q0

• g’0=(ρa-ρ0)/ ρa

n Volume Flux• Q0=u0a0

n Momentum Flux• M0=u0Qo

n Buoyancy Flux• J0=g’0Q0

• g’0=(ρa-ρ0)/ ρa

Turbulent Buoyant Jet Mixing

Length Scales 1

n Jet to Plume Scale

• LM = M03/4/J0

1/2

n Distance From Jet-like Flow To Plume-like Flow In A Stagnant Ambient

n Jet to Plume Scale

• LM = M03/4/J0

1/2

n Distance From Jet-like Flow To Plume-like Flow In A Stagnant Ambient

Jet to Plume Scale LM

Length Scales 2

n Jet to Crossflow Scale• Lm = M0

1/2/ua

n Distance Of

Transverse Jet

Penetration

Before Ambient

Current Deflection

n Jet to Crossflow Scale• Lm = M0

1/2/ua

n Distance Of

Transverse Jet

Penetration

Before Ambient

Current DeflectionJet to Crossflow Scale

Lm

Length Scales 3

n Other Scales account for

ambient density

stratification, buoyant

plume behavior, etc.

• Lb, Lm’,L b’, etc.

• Local Water Depth H

n Other Scales account for

ambient density

stratification, buoyant

plume behavior, etc.

• Lb, Lm’,L b’, etc.

• Local Water Depth H

Jet to Plume Scale LM

Plume to Crossflow Scale Lb

Boundary Interaction. . . 1• Gradual Interaction

Boundary Interaction . . . 2• Stable w/Buoyant Intrusions

Boundary Interaction . . . 3• Unstable Stable w/Full Vertical Mixing

Boundary Interaction . . . 4• Unstable w/Buoyant Intrusions & Re-

stratification

Boundary Interaction . . . 5• Near-field Attachments Processes

Why Use an Expert System?n Widespread Model

Misapplicationn Assist In Technology

Transfern Need For Both Near-Field

& Far-Predictionsn Ease of Usen Common Languagen Model flexibilityn Rigorous Rule-verified

Analysisn Documentationn Outfall Design Advicen Learning Environment

n Widespread Model Misapplication

n Assist In Technology Transfer

n Need For Both Near-Field & Far-Predictions

n Ease of Usen Common Languagen Model flexibilityn Rigorous Rule-verified

Analysisn Documentationn Outfall Design Advicen Learning Environment

An atmospheric example of turbulent buoyant jet mixing in

a stratified shear flow.

The CORMIX-GI Systemn “Intelligent” GUIn Rule-verified and

documented analysis

n Hydrodynamic model suite

n Regulatory Decision support

n Sensitivity Analysis

n Design Optimization

n “Intelligent” GUIn Rule-verified and

documented analysis

n Hydrodynamic model suite

n Regulatory Decision support

n Sensitivity Analysis

n Design Optimization

CORMIX Scope

n Plume Dilution and Mixing Behavior• Suspended Sediment / Tracer & 1st-Order Decay

n Plume Geometry-Boundary Interactionsn Space / Time Scale

• 10-2 - 104 meters / 1.0 - 104 seconds

n Plume Dilution and Mixing Behavior• Suspended Sediment / Tracer & 1st-Order Decay

n Plume Geometry-Boundary Interactionsn Space / Time Scale

• 10-2 - 104 meters / 1.0 - 104 seconds

CorVue side and plan views of a single port flow class V2 mixing zone.

CORMIX1- Single Port Discharges(Technical Report EPA 600/ 3-90/012)

n Covers 90-95% Of Single-port Submerged Cases

n Simulates Near-field Boundary Attachments

n Contains Approximately 35 Flow Classifications

n Covers 90-95% Of Single-port Submerged Cases

n Simulates Near-field Boundary Attachments

n Contains Approximately 35 Flow Classifications This laboratory experiment shows

terminal level plume trapping in a stagnant density-stratified ambient

fluid.

CORMIX2- Multiport Diffuser Discharges(Technical Report EPA 600/ 3-91/073)

n Covers 80-85% Of Multiport Diffusers

n Includes Intermediate Field Effects

n Staged, Parallel, And Alternating Designs

n Contains Approximately 25 Flow Classifications

n Covers 80-85% Of Multiport Diffusers

n Includes Intermediate Field Effects

n Staged, Parallel, And Alternating Designs

n Contains Approximately 25 Flow Classifications

A modern multiport diffuser under construction for wastewater disposal

at Cayuga Lake, NY.

CORMIX3- Surface Buoyant Discharges

(Defrees Lab Report by Jones, Nash, & Jirka 1996)

A surface discharge where tides influence initial mixing.

n Covers 85-90% Of Buoyant Surface Discharges

n Can Model Tidal Effects On Plume Dilution

n Contains Approximately 12 Flow Classifications

n Covers 85-90% Of Buoyant Surface Discharges

n Can Model Tidal Effects On Plume Dilution

n Contains Approximately 12 Flow Classifications

D-CORMIX- Continuous Pipeline Discharges

A continuous pipeline dredge discharges large volumes of water and suspended

sediment.

n Covers 85-90% Of Continuous Pipeline Sources

n Predicts Plume Suspended Sediment

n Uses CORMIX1 & CORMIX3 Flow Classifications

n Covers 85-90% Of Continuous Pipeline Sources

n Predicts Plume Suspended Sediment

n Uses CORMIX1 & CORMIX3 Flow Classifications

CORMIX Flow Classification

n CORMIX1 flow Classification For Uniform Layersn About 80 within CORMIX

n CORMIX1 flow Classification For Uniform Layersn About 80 within CORMIX

Rule-base Examplen Backward

(deductive) chaining search strategies

n Forward (inductive) logic

n Provides a Learning Environment

n Design Advice

n Backward (deductive) chaining search strategies

n Forward (inductive) logic

n Provides a Learning Environment

n Design Advice

A CORMIX1 rule for V2 flow classification.

Rule-tree Example

n Methodical analysis

n Learning Environment

n Design Advice

n The complete rule base contains over 2000 rules

n Methodical analysis

n Learning Environment

n Design Advice

n The complete rule base contains over 2000 rules

A CORMIX1 rule for V2 flow classification.

CORMIX Hydrodynamic Simulation

n Regional Flow Models (CORMIX Modules)n CORMIX Hydrodynamic Simulation Modules

• Integral (CORJET near-field, MOD340 density current)• Length Scale (Boundary Interaction, MOD133)• Diffusion Equation (Far-field, MOD161)

n Regional Flow Models (CORMIX Modules)n CORMIX Hydrodynamic Simulation Modules

• Integral (CORJET near-field, MOD340 density current)• Length Scale (Boundary Interaction, MOD133)• Diffusion Equation (Far-field, MOD161)

Near-field and far-field mixing for a buoyant plume.

CorDocs User Help Documentation

n GUI access to over 1000 pages of technical reports in HTMLn GUI access to over 1000 pages of technical reports in HTML

CorDocs hypertext help documentation available in your web browser.

CorSpy Outfall Visualization

n 3D and 2D Viewsn Interactive Zoom, Rotate, Translaten Alternating, Staged, Unidirectional w/wo Fanningn Outfall Hydraulics w/T. Blenniger at IFH

n 3D and 2D Viewsn Interactive Zoom, Rotate, Translaten Alternating, Staged, Unidirectional w/wo Fanningn Outfall Hydraulics w/T. Blenniger at IFH

The CorSpy shows an alternating multiport diffuser with fanning.

CorSens Sensitivity Study Tool

n Automatically Vary Discharge and Ambient Variablesn Full CORMIX Rule-base Verification

n Automatically Vary Discharge and Ambient Variablesn Full CORMIX Rule-base Verification

CorSens tool automatically creates time series data.

CorVue Hydrodynamic Visualization

n 3D and 2D Viewsn Interactive Zoom, Rotate, Translate, Distortionn Concentration vs. Distance Graphs

n 3D and 2D Viewsn Interactive Zoom, Rotate, Translate, Distortionn Concentration vs. Distance Graphs

CorVue Visualization of near-field and far-field mixing for a buoyant plume.

CorJet Near-field Jet Integral Model

n For Stable Discharges w/o Attachmentsn Detailed Near-field Analysisn Arbitrary Stable Ambient Density Profiles

n For Stable Discharges w/o Attachmentsn Detailed Near-field Analysisn Arbitrary Stable Ambient Density Profiles

FFL Far-field Plume Locator

n Post Processorn Shallow River Environmentsn Based on Cumulative Discharge Method (Yotsukura & Sayre,

1976)

n Post Processorn Shallow River Environmentsn Based on Cumulative Discharge Method (Yotsukura & Sayre,

1976)

FFLocatr adjusts plume dimensions in the far-field to reconcile with dye study data.

CORMIX Validation

A) Validation of CORMIX1; B) CORMIX2 (Source: Fergen, et al. 1994 SEFLOE)

C) Validation of CORMIX3; D) D-CORMIX (Source Jones et al. 1995, and Doneker & Jirka (1997)

A B

C D

n Wide range of outfalls

n Over 10 years of application

n Predictions within +/- 50% of std. Deviation

n Over 18 independent validation studies since 1990

n Wide range of outfalls

n Over 10 years of application

n Predictions within +/- 50% of std. Deviation

n Over 18 independent validation studies since 1990

CORMIX Development History• 1986-1995: USEPA: Cornell University• 1996-present: USEPA: OGI/IFH

Portland, Oregon youth of 1938 join the mayor in protest of Willamette River pollution. Photo: Oregon Hist. Soc.

Research Needsn Model Certification QA/QC

• ISO14000• Validation Database• “Benchmarking” & Standard • Field Data/Monitoring

n Boundary Interaction• Stratified Terminal Levels• Attachment/Detachment• Bottom Density Current

n Sediment Density Currents• Deposition Characteristics• Chemistry/Reaction

Processes• Settling Rates/Mixing

n Area Sources: GW/SW interaction

n Comparison w/CFD Modelsn Linkage with Far-field Models

n Model Certification QA/QC• ISO14000• Validation Database• “Benchmarking” & Standard • Field Data/Monitoring

n Boundary Interaction• Stratified Terminal Levels• Attachment/Detachment• Bottom Density Current

n Sediment Density Currents• Deposition Characteristics• Chemistry/Reaction

Processes• Settling Rates/Mixing

n Area Sources: GW/SW interaction

n Comparison w/CFD Modelsn Linkage with Far-field Models

The CORMIX Systems Approach

CORMIX-GI tools integrate to form a comprehensive design system.

n Minimal Data Inputn Range Of Applicability

• CORMIX1,2, & 3n Widespread Application

• Over 1800 Users Worldwide

n Documented Analysisn Common Language

• Regulators/Applicantsn Integrated design/analysis

systemn http://www.cormix.info

n Minimal Data Inputn Range Of Applicability

• CORMIX1,2, & 3n Widespread Application

• Over 1800 Users Worldwide

n Documented Analysisn Common Language

• Regulators/Applicantsn Integrated design/analysis

systemn http://www.cormix.info