ME6203 Mass Transport

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ME6203 Mass Transport

• ME 6203 Mass Transport
• Objectives
• To examine fundamental principles of diffusive
  and convective mass transfer and their
  applications in analysis and syntheses of
  engineering systems.
• Outcomes expected
• Ability to develop appropriate physical models
  and corresponding mathematical models for
  engineering systems involving transfer of mass
• (b) Ability to solve mathematical formulations
  and interpret them for design, analysis or
  research, and
• (c) Ability to critically assess technical
  literature and utilize it in formulating and
  solving inter-disciplinary engineering problems
  involving mass transport.

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Outline

• Principles of transport phenomena differential
  formulations of conservation equations of mass,
  momentum and energy scale analysis diffusion in
  gases, liquids and solids estimation methods for
  diffusivities free and forced convection mass
  transfer inter-phase mass transfer overall mass
  transfer coefficients simultaneous heat and mass
  transfer applications to engineering problems
  involving absorption, adsorption, drying etc.

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MASS TRANSPORT (ME6203)Lecture Time Friday 1800
2050 hrs E3-06-03Professor Arun S.
MujumdarDepartment of Mechanical and Production
EngineeringRoom EA-05-38 Tel [phone]
mpeasm_at_nus.edu.sg

• Why Study Mass Transfer (Transport)?
• Numerous applications much more diverse and
  commonplace than pure heat transfer. Following is
  a short list of selected examples
• Evaporation of liquids and suspensions
• Drying over 100 types commercially used
• Biomedical devices artificial lungs, kidneys
  etc.
• Desulphurisation of flue gases from power plants
• Gas cleaning 9wet scrubbers)
• Controlled drug release technology
• Flavor retention in food processing
• Frying, cooking of foods

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Application areas (contd)

• Frying, cooking of foods
• Biochemical processing brewing operations
• Air-, water-pollution thermal pollution
• Soil decontamination
• Purification of gases/liquid/solid mixtures
• Metallurgical processing
• Evaporation of water into air in a cooling tower
• Drying of wood, paper, polymers, foods, biotech
  products and textiles
• Leakage of helium from the laser of a copying
  machine
• Diffusion of carbon into iron during
  case-hardening of a gear wheel

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More applications

• Manufacture of petroleum products
• Mineral processing
• Catalytic oxidation of carbon monoxide and
  unburnt hydrocarbons in an automobile catalytic
  converter
• Measurement of humidity using wet and dry
  thermocouples
• Combustion of pulverized coal in a power plant
  furnace
• Combustion of kerosene droplets in a gas turbine
  combustion chamber
• Combustion of iron in oxy-acetylene steel cutting
• Absorption of sulfur dioxide into an alkaline
  solution in a power plant flue-gas scrubber
• Doping of semiconductors for transistors
• Discharge of a lead-acid battery
• Power generation by a fuel cell

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Application areas -contd

• Aeration of sewage for biological treatment
• Evaporation and condensation in gas-controlled
  heat pipes
• Ablation of a heat shield on a re-entry vehicle
• Erosion of a graphite or rhenium nozzle in a
  solid-propellant rocket
• Scrubbing of radioactive nuclides in a nuclear
  reactor pressure-suppression pool following an
  accident involving core degradation
• Oxidation of Zircalloy fuel rod cans by steam
  following a loss-of-coolant (LOCA) accident in a
  boiling-water nuclear reactor
• Separation of oxygen and nitrogen in the
  separation column of a gaseous oxygen plant
• Blood oxygenation in a rotating-disk oxygenator
  during open-heart surgery
• Desalination of brackish water by reverse osmosis
• Etc etc

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Term Paper assignment

• About the Term Paper Requirement
• This assignment is designed to give you
  opportunity to research independently a topic of
  your interest, carry out the necessary literature
  search and present it in writing and orally. This
  will require self-study and provide experience in
  written and oral communication. Details of the
  format for the technical paper and final
  presentation will be provided in the class.
• For the Term Paper assignment, you may choose any
  one of the following options
• Review critically a narrow subject area within
  the scope of the course
• Write a critical review of a published paper in
  heat and mass transfer which includes a
  mathematical treatment or simulation of a
  heat/mass transfer process
• Design strategy for a mass transfer operation
  e.g. drying, evaporation etc
• Simulation of a mass transfer operation with or
  without heat transfer( may be analytical or
  computational using MATLAB,MATHEMATICA or other
  software
• Critical evaluation of estimation or measurement
  techniques for diffusivities of gases or liquids
  or solids

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Term Paper-contd

• A list of appropriate journals, reference books
  etc will be supplied to help you select a
  suitable topic.
• As part of this course, a half day workshop is
  being organized on Saturday, March 14, 2009
  which will cover a number of topics that are
  directly relevant to the main theme of this
  course. It will broaden your knowledge of the
  subject and make you familiar with the wide range
  of engineering applications of mass transport (or
  transfer) fundamentals to practice.
• Paper may be prepared in groups of 2-3 under some
  conditions to be discussed

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Mid Term Quizzes, Assignments

• First quiz will be held in mid-February second
  in late March
• Several sets of home assignments will be given.
  Please submit individual solutions. Please use
  both sides of paper for both printed and
  hand-written work. Also, term papers maybe
  submitted in hard copy ( use both sides of paper)
  and soft copy format. Oral presentation PPTs
  should also be submitted for evaluation on CD.

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Additional information

• Reading assignments will be given from textbook
  as well as IVLE or Prof. Mujumdars website
• http//serve.me.nus.edu.sg/arun
• Sample term paper presentations are available on
  this site (Teaching Resources/ Mass Transport)
  for information
• Please review basic engineering maths- solution
  of ODEs and linear PDEs. Also, basic fluid
  mechanics and heat transfer at undergrad level.

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About modeling, levels of math models,
dimensional analysis etc

• Why model?
• Different levels of modeling
• Role of experiments
• Use of dimensional analysis
• Physical meaning of key dimensionless groups e.g.
  Reynolds, Prandtl, Schmidt, Sherwood, Nusselt
  number etc.
• Analogy with heat transfer

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Please review

• Mass transport by diffusion and by convection
• Dr Balaya will consider diffusion in solids,
  liquids and gases
• This will be followed by convective diffusion
  principles, math modeling and numerous
  applications
• First study simple flows e.g.. Boundary layers,
  tube/channel flows. Jet flows etc
• Next, engineering applications in drying,
  humidification /cooling etc and energy systems
  e.g. fuel cell modeling

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From undergrad fluid mechanics and heat transfer,
review..

• Derivation of conservation equations of mass,
  momentum and energy- last needed for simultaneous
  heat and mass transfer
• Analogy with momentum and heat transfer- where
  appropriate
• Meaning of dimensionless groups
• Etc etc