CORMIX Models for Mixing Processes - · PDF fileNear-field Models • Jet integral models – Integrate dynamic terms along trajectory, across cross-sectional plane • simple ordinary

© 1998-2008 Robert L. Doneker MEDRC Mixing Zone Model Workshop All Rights Reserved CORMIX Models

Balloon aerial infrared survey of a regulatory mixing zone.

CORMIX Models for Mixing Processes

© 1998-2008 Robert L. Doneker MEDRC Mixing Zone Model Workshop All Rights Reserved CORMIX Models 3 - 2

Section Outline

• Types of mixing models

• CORMIX description

• Features/components

• System requirements

• Ambient schematization

• Input data requirements

• CORMIX1 single port specification


General Features of CORMIX

• Predicts quantitative & qualitative features of mixing process

• Covers NPDES regulatory concerns for conventional & toxic discharges

• Provides guidance to improve designs and associated dilutions

Figure 3-3: Chronic and acute Regulatory Mixing Zones for conventional and toxic discharges, respectively


Near-field vs. Far-Field Mixing

• Near-field mixing– Close to source– Region of “buoyant jet mixing”

• Time scales of seconds to minutes

• Space scales of 1-m to 100-m– Source properties dominate

mixing• Far-field mixing

– Ambient conditions dominate mixing

• Time scales of minutes to hours• Space scales of 10-m to 1000-m

• Boundary Interaction– Provides transitions from

near-field to far-field Mixing

Near-Field

Far-Field

Side View


Predictive Models for Mixing Processes

A) Complete Models• Single domain with one set of governing equations

– Drawbacks• Numerical limitations• Turbulence Models• Boundary Conditions

• Fluent, Flow3D, STAR3D

B) Zone Models• Divide domain into sub-regions with specific mixing processes

– Allows use of simplified equations• Jet Integral Models• Mixing Zone Expert System - CORMIX


Near-field Models• Jet integral models

– Integrate dynamic terms along trajectory, across cross-sectional plane• simple ordinary differential equations

– empirical equations for turbulence closure: rate of entrainment, ambient drag force, and frontal spreading velocity

– fast & easy• BUT: infinite, steady ambient waters (no boundary interactions)

• Mixing zone models (CORMIX)– Amplifications for boundary interaction, unstable near-field, buoyant

spreading, passive diffusion – full range of discharge geometries and ambient conditions– boundary interaction, buoyant spreading and passive diffusion – few parameters

• easy input, fast calculations, no calibration– Limits: only simple reversals, 1st order decay, single source


Far-field Models

Eulerian hydrodynamics and transport models• Solve unsteady, baroclinic, shallow water equations in 3D (hydrostatic)• Orthogonal curvilinear co-ordinates • Terrain-following, sigma - coordinate system • k-ε

turbulence closure• Water quality module: Mancini model for coliform inactivation

Limits• Far-Field model ignores dominant NF processes or treats them

superficially• Spatial and temporal resolution limited by calculation power• Difficult to match boundary / initial conditions, shear turbulence


Physical Mixing Processes


Mixing Models for Coastal Outfalls

Model Scale Typical Grid Resolution

Ocean Circulation Ocean wide 10 - 100 of km

Coastal Circulation (Far-field) Coastal Zones, Estuaries 0,1 - 1km

Discharge Mixing Models (Near-field) Local (scale of outfall) no grid;

predictions up to 100m - 5km


Modeling Approaches


CORMIX

CORMIX1: Single Port Discharges• Doneker & Jirka, 1989

• Bounded Channels: Rivers, estuaries

• Unbounded Channels: Coastal, lakes

• Crossflows (or stagnant)• Buoyant (positively, negatively, or

neutral)

• Uniform or Stratified Ambient– Up to 3 stratified density layers

• Submerged, Near & Above surface

• Brine & Sediment discharges• Covers > 95 % of cases

Figure 3-1: CorSpy visualization of single port discharge

Cornell Mixing Zone Expert System


CORMIX

CORMIX2: Multiport Diffusers• Akar & Jirka, 1990

• Same conditions as CORMIX1

• 3 Major Diffuser Types:– Alternating, Unidirectional,

Staged• Covers > 80 % of cases

CORMIX3: Surface Discharges• Jones & Jirka, 1990

• Same conditions as CORMIX1

• Up to 3 ambient density levels

• Covers > 90 % of cases Figure 3-2: CorSpy visualization of A) multiport diffuser and B) surface discharge

A)

B)


Why An ”Expert” or ”Rule Based” System?• Data Driven System – specify data, system selects the model

• Proper model choice• Correct model application

• Guides in data acquisition

• Addresses CREM guidelines - http://epa.gov/osp/crem.htm• Flexible:

– Screening of alternatives– Switch to other models

• Continuous update of knowledge base• Documented analysis

– Not a ”black box”• Common Framework

– Regulator– Applicant

• Design System

• Advanced CAD 3-D Graphics tools (e.g. Figures 3-1, 3-2, 3-4)

• Teaching environment– Adapts to user

http://epa.gov/osp/crem.htm



• Flags undesirable designs

• Data screening

• Provides descriptions of mixing processes

• Figure 3-5 shows conceptual overall structure

Figure 3-4: CorVue 3D Mixing Zone Visualization



Figure 3-5: CORMIX Conceptual Structure


CORMIX Systems Requirements

• Windows NT/2000/XP– Win 95/98 may require a dcom patch – MixZon does not offer support to Win95/98 installations

• Minimum Pentium II with AGP graphics for GT versions

• Pentium for G versions

• Minimum system configuration– 16 MB RAM, 40 MB free hard drive space– Internet access (www.mixzon.com)

• Run Times: seconds to 20 minutes depending on system and simulation type

• Recommended system: Windows XP with Pentium IV


CORMIX Program Elements

GUI DATA ENTRY PROGRAM CONTROL Module

• Interactive windows Graphical User Interface (GUI) collects all data

• Tab forms: Project, Effluent, Ambient, Discharge, Mixing Zones, Output, Processing

• Extensive advice available on CORMIX definitions, applications, and interpretation under help menus

• http://www.cormix.info;

• http://www.mixzon.com

http://www.cormix.info/

http://www.mixzon.com/


CORMIX Program Elements

Figure 3-6: CORMIX v5.0 Graphical User Interface (GUI)


PARAMETER CALCULATION Module

• Automatically computes all flow parameters• Length scales, fluxes, other values• Describes near -field flow properties

A) Discharge Quantities

Jet to Plume Transition Length Scale:LM= M0

3/4/J01/2 [ L ]

Figure 3-7: Parameter Calculations for buoyant jet mixing


FLOW CLASSIFICATION Module

• Classifies the discharge/environment boundary interaction

• Develops a generic qualitative description of flow patterns

• Specifies flow protocol for hydrodynamic simulation

• Heart of CORMIX ”knowledge base”

• Compilation of 200 years of hydraulic research

Figure 3-8: CORMIX1 Classification system for plumes trapped by ambient density stratification.


CORMIX Flow Class

Table 4-1: Flow Class Categories and DescriptionsCORMIX1 (70 flow classes)

Classes S Flows trapped within linear stratificationClasses V,H Positively buoyant flows in uniform density layer Classes NV,NH Negatively buoyant flows in uniform density layerClasses A Flows affected by dynamic bottom attachmentsClasses I Images of S,V,H e.g.: IS, IV1, IH2, IPV3, IPH4 (Near Surface)

CORMIX2 (62 flow classes)

Classes MS Flows trapped within linear stratificationClasses MU Positively buoyant flows in uniform density layerClasses MNU Negatively buoyant flows in uniform density layerClasses I Images of MS,MU,MNU e.g.: IMS, IMU, IMPU (Near Surface)

CORMIX3 (11 flow classes)

Classes FJ Free jet flows w/o near-field shoreline interactionClasses SA Shoreline attached discharges in crossflowClasses WJ Wall jets/plumes from discharges parallel to shorelineClasses PL Upstream intruding


HYDRODYNAMIC SIMULATION Module

• FORTRAN hydrodynamic simulation program for selected flow classification

• Singe Port Discharge – CORMIX1

• Submerged Multiport Diffusers - CORMIX2

• Shoreline/Surface Discharges - CORMIX3

• Coastal Brine/Sediment Effluents - DHYDRO

• CorJet - Stable Near-field post-processor model for CORMIX1 and CORMIX2

• FFL – Plume far-field locater

• CorSens – Sensitivity Study Post-processor

• CorTime – Time series analysis far-field model linkage

• Contains about 400k lines of code


SUMMARY Module

• Summarizes HYDRO simulation results

• Specifies concentrations at regulatory mixing zones (TDZ,RMZ)

• Gives expert advice for design iteration

Figure 3-9: Summary Report


User Help In GUI

• Multiple-levels of help available in GUI– Place mouse pointer over entry box- yellow tool tip hint popup appears– Right mouse click in box – help popup box appears– Press “F1” key in box – User Manual Section (CorDocs) loaded in

browser

Figure 3-10: A) Tool Tips (mouse over); B) Tool Tip Help Popup (right click)

A) B)


User Help In GUI

• "Help Popup Window“ - “Online Help" displays “context sensitive online help" page with additional information and illustrations

• Press “F1” key in box - User Manual Section loaded into browser

Figure 3-11: A) Online Tool Tip Help; B) Online User Manual Section (F1 Key)

A) B)


User Help In GUI

• In CORMIX UI, Pre-post processing (CorSpy, CorVue, etc.) tools..

– “Help -Online User Manual" menu option

• GUI Help

– “Online Help” button• CorHelp GUI Help

– “Online User Manual” button• CorDocs

• Search Tool at http://www.cormix.info using the "Search" link

• FAQ: http://www.cormix.info/faq.php

• E-mail to: [email protected] 3-12: Search on http://www.cormix.info


http://www.cormix.info/faq.php


© 1998-2008 Robert L. Doneker MEDRC Mixing Zone Model Workshop All Rights Reserved CORMIX Models

Remote Sensing - Outfall Monitoring

• Source Characterization

• Outfall Inspection

• Dual Frequency Identification Sonar (DIDSON)

• Underwater Video

DIDSON acoustic camera image of multiport diffuser in turbid river.


Remote Sensing – Mixing Model Verification


Section Summary

• Description of mixing models

• The CORMIX approach

• CORMIX components

• Schematization of ambient data

• General input data requirements

• CORMIX1 single port specification

• Remote sensing systems for source inspection and mixing model verification

Documents

CORMIX Models for Mixing Processes - · PDF fileNear-field Models • Jet integral models – Integrate dynamic terms along trajectory, across cross-sectional plane • simple ordinary