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EngineeringCFD General Presentation - Web Version

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EngineeringCFD General Presentation - Web Version Powered By Docstoc
					EngineeringCFD
      Specialists
  In Fluid Dynamics
                        Contents

I.     EngineeringCFD
II.    Introduction to CFD
III.   Capabilities and Scope
IV.    Multiphase Examples
V.     Case Studies
VI.    Summary
                         Principle Engineer

Curtis Marsh
• 13 years design experience for the
  chemical process industry.
• Expert Computational Fluid
  Dynamics (CFD) analyst.
• Specialising in multiphase and
  multiphysics simulations.
• Proven technical ability supported by
  excellent inter-personal skills.
                                     Design Services


                       Rusal
Vaudreuil
                               FLSmidth


            Windalco
                        Equipment                        Engineering
                         Suppliers                      Consultancies
                                                                               RioTinto
                                                                               Alcan
                                                                               QAL
                                     Chemical Process                          Yarwin
                                         Plants           SKM
                                                          Momentum
                                                                        Cadburys
                                                                        Fonterra
                                                                        Hulme Supercars
Project Integration
                          What is CFD?

• CFD = Computational Fluid Dynamics
  – Computer models that predict how fluids behave

  – Uses mathematical models to describe aspects of
    fluid behaviour

  – Use commercial CFD software from ANSYS

  – Based on the finite volume approach

                                          Know the basics?
                                          Click here to skip
                        CFD – Step 1

Geometry Creation
• Create from 2D
  drawings
• Import from a range
  of CAD packages
   – Parasolid
   – IGES
   – STEP
   – ACIS
                    CFD – Step 2

• Develop mesh
• Define boundary
  conditions
                        CFD - Step 3

• Setup boundary
  conditions
• Initialise solution
                         CFD – Step 4

• Iterate to
  convergence
  – Steady state
    problems
  – Transient problems
                     CFD – Step 5

• Post-Process
  Results
• Quantify
  –   Mass flux
  –   Velocities
  –   Pressures
  –   Forces
  –   Lift/Drag
  –   Free surface
                       CFD Capabilities

• Single phase          • Heat transfer

• Multiple phases       • Mass transfer

• Chemical species      • Phase change

• Chemical reactions    • Mechanical movement

• Combustion            • Ventilation

• Erosion               • Solidification
                                 Equipment Types
•   Piping systems     •   Agitators
•   Pressure vessels   •   Mixing devices
•   Cyclones           •   Choke valves
•   Dryers             •   Gas dispersion
•   Filters            •   Gas lift devices
•   Calciners          •   Slug catchers
•   Furnaces
•   Burners
•   Tanks
•   Flash vessels
•   Overflows
•   Launders
•   Pumps
                           Multiphase Examples
Free Surface
Model
Can be applied to:
   Launders/Overflows

   Sloshing in Tanks

   Slug Flow

   Gas-Liquid Separators

   Water-Oil Separation


 Link to animation
 (engineeringCFD.com)
                         Multiphase Examples
Discrete Phase
Model
Can be applied to:
   Particle separation

   Particle impact

   Sprays

   Droplets

   Erosion
                        Multiphase Examples

Granular
Solids Flows
Can be applied to:
   Cyclones

   Pneumatic conv.

   Settling solids




 Link to animation
 (engineeringCFD.com)
                        Multiphase Examples
Rotating
Equipment
Can be applied to:
   Agitated Tanks

   Pumps

   Blowers

   Compressors




 Link to animation
 (engineeringCFD.com)
                        Case Studies

• Project examples

  – Flashing Flows (Rusal Aughinish)

  – Alumina Calciners (FLSM/RioTinto/SKM)

  – Segregated Fluids
CASE STUDY:
FLASHING FLOWS
Rusal Aughinish
Ireland
Alumina Refinery
1.8 million tonnes pa.
 Flashing Flows
Complex multiphase flow
• Historically difficult to design
• Rapid phase change from
  liquid to vapour
• Potentially extreme erosion
  rates
Objective
• Design a balanced system
  which maintains stable levels
  within each vessel
                 Calculation Steps

       FLUENT    Determine Flow Field

                    Saturation Temp


                       Super Heat

EngineeringCFD     Bubble Nucleation
  Subroutine

                     Interfacial Area


                 Mass & Energy Transfer
                         Validation

Experiment   7.01 kg/s

Calculated   7.12 kg/s
Flow
             (+1.6%)
                             Flash Vessels

• Project scope was
  to determine the             Orifice
  effect of piping              Plate
  modifications

Process Data      910 kg/s

Calculated Flow   980 kg/s

                  (+8%)
                       Flash Tank Projects

Application of the Flashing Flow Model
  – Piping design for multiphase flow

  – Orifice plate sizing

  – Evaluation of proposed vessel modifications

  – Development of new inlet nozzles to improve
    separation within flash vessels.
CASE STUDY:
ALUMINA CALCINERS
FLSmidth
RioTinto Alcan
Rusal Aughinish
Sinclair Knight Merz
Queensland Alumina
                    Design Challenges
• Complex processes
  – Combustion / pyrolytic reactions
  – High Solids Loading
  – Heat Transfer
• And complex problems
  – Particle breakdown
  – Refractory erosion
  – Emission targets
  – Limits on production
                          Calciner Furnaces
Complex coupled
physical processes
–   Combustion            Solids

–   High Solids Loading
–   Calcination process
–   Heat Transfer
–   Changing gas
    composition
                             Burners    Gas Flow
                       Calciner Furnaces




Link to animation
(engineeringCFD.com)
                           Projects
• Many projects have benefited from our
  modelling expertise
  – Development of new furnace geometries
   (RUSAL/FLSM)
  – Change gas distribution to improve combustion
   (RUSAL)
  – Modify geometry to increase capacity
   (SKM)
  – Developed new hydrate feed points
   (RioTinto/FLSM)
CASE STUDY:
SEGREGATED FLUIDS
                                   Segregated Fluids

VOF free                             VOF Model
surface model
• Suitable for a   Gas Mass Flux
  wide range
  of flow
  regimes




                                                 Liquid Mass Flux
                         Fluid Properties

• Key Physical Processes
  – Surface tension

  – Wall contact angle

  – Compressibility of gas phase

  – Pressure distribution

  – Wall/body interaction forces
                  Pipe Flow Example

  Ideal Gas
 ρ = 50 kg/m3

Surface Tension
  0.014 N/m
  Light Liquid
 ρ = 700 kg/m3
Surface Tension
    0.1 N/m

 Heavy Liquid
ρ = 1200 kg/m3              Contact Angles
                             90 degrees
                       Complex Flow




Link to animation
(engineeringCFD.com)
                     EngineeringCFD

Adding Value to the design process:
• Proof of concept

• Determine key design variables

• Extract key performance data

• Explore the full design envelope

• Problem solving new & existing equipment
                    EngineeringCFD

Ultimately EngineeringCFD provides:
• Rapid project development

• Risk mitigation

• Reduced commissioning/maintenance costs

• Greater process efficiencies
EngineeringCFD.com

				
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posted:4/21/2010
language:English
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