Environmental Engineering Course Note 8 (Transport Processes II) Joonhong Park Yonsei CEE Department 2015. 5. 20 CEE3330 Y2013 WEEK3.

Slides:

Advertisements

Similar presentations

Particle Fall through the atmosphere

Advertisements

CLASTIC TRANSPORT AND FLUID FLOW

An overview Colloids An overview

Week # 2 MR Chapter 2 Tutorial #2

3. The Motion of Particles Drag force d particle diameter V flow velocity Spherical particle, Re < 1 Drag coefficient A projected area.

Motion of particles trough fluids part 1

Dept of Chemical and Biomolecular Engineering CN2125E Heat and Mass Transfer Dr. Tong Yen Wah, E , (Mass Transfer, Radiation)

Chapter 9 Solids and Fluids 1. Introduction 2. Fluids at Rest 3. Fluid Motion.

Motion of particles trough fluids part 2

高等輸送二 — 質傳 Lecture 7 Fundamentals of Mass Transfer

Aerosols By Elizabeth Dahl (2005) Edited by Ted Dibble (2008)

15. Physics of Sediment Transport William Wilcock (based in part on lectures by Jeff Parsons) OCEAN/ESS

Kelvin Effect: Physical Cartoon Equilibrium vapor pressure is higher over a curved surface than a flat one. Important for nucleation of new particles,

Viscosity. Average Speed The Maxwell-Boltzmann distribution is a function of the particle speed. The average speed follows from integration.  Spherical.

1 MAE 5130: VISCOUS FLOWS Stokes’ 1 st and 2 nd Problems Comments from Section 3-5 October 21, 2010 Mechanical and Aerospace Engineering Department Florida.

Convection Prepared by: Nimesh Gajjar. CONVECTIVE HEAT TRANSFER Convection heat transfer involves fluid motion heat conduction The fluid motion enhances.

Evaporation Slides prepared by Daene C. McKinney and Venkatesh Merwade

Resistance in Fluid Systems

Molecular Transport Equations. Outline 1.Molecular Transport Equations 2.Viscosity of Fluids 3.Fluid Flow.

Particle Aerodynamics S+P Chap 9. Need to consider two types of motion Brownian diffusion – thermal motion of particle, similar to gas motions. –Direction.

Resistance In Fluid Systems 4.2. Define Drag For a solid object moving through a fluid or gas, drag is the sum of all the aerodynamic or hydrodynamic.

Lesson 21 Laminar and Turbulent Flow

Boundary Layer Laminar Flow Re ‹ 2000 Turbulent Flow Re › 4000.

Basic Laws of Gases and Particulates

高等輸送二 — 質傳 Lecture 8 Forced convection

PM3125: Lectures 7 to 9 Content of Lectures 7 to 9:

Presentation Slides for Chapter 15 of Fundamentals of Atmospheric Modeling 2 nd Edition Mark Z. Jacobson Department of Civil & Environmental Engineering.

CEE Joonhong Park Copy Right Environ. Eng. Course Note 9 (Reactor I) Review of Ideal Reactor Models - CMBR - CM(C)FR - PFR Advanced Ideal.

U N C L A S S I F I E D Conversion from Physical to Aerodynamic Diameters for Radioactive Aerosols Jeffrey J. Whicker Los Alamos National Laboratory Health.

Air / Water Gas Exchange The distribution of a chemical across the air-water interface between the atmospheric gas phase and the water dissolved phase.

States of Matter. The Kinetic-Molecular Theory Explains the properties of gases, liquids, and solids.

Motion of particles trough fluids part 1

Fluid Resistance.

Prof. Mohammad Asif Room 2B45, Building 3

2. Brownian Motion 1.Historical Background 2.Characteristic Scales Of Brownian Motion 3.Random Walk 4.Brownian Motion, Random Force And Friction: The Langevin.

15. Physics of Sediment Transport William Wilcock (based in part on lectures by Jeff Parsons) OCEAN/ESS 410.

Quantification of the Infection & its Effect on Mean Fow.... P M V Subbarao Professor Mechanical Engineering Department I I T Delhi Modeling of Turbulent.

Chapter 16 Kinetic Theory of Gases. Ideal gas model 2 1. Large number of molecules moving in random directions with random speeds. 2. The average separation.

INTRODUCTION TO CONVECTION

Chapter 4.2 Notes Resistance in Fluids. When one solid object slides against another, a force of friction opposes the motion. When one solid object.

Kinetic Properties (see Chapter 2 in Shaw, pp ) Sedimentation and Creaming: Stokes’ Law Brownian Motion and Diffusion Osmotic Pressure Next lecture:

Sedimentology Flow and Sediment Transport (1) Reading Assignment: Boggs, Chapter 2.

Prof. Jiakuan Yang Huazhong University of Science and Technology Air Pollution Control Engineering.

Heat Transfer Su Yongkang School of Mechanical Engineering # 1 HEAT TRANSFER CHAPTER 6 Introduction to convection.

SETTLING AND SEDIMENTATION.

Environmental Engineering Lecture Note Week 10 (Transport Processes) Joonhong Park Yonsei CEE Department CEE3330 Y2013 WEEK3.

Gravitational Force  Gravity= a force of attraction between objects, “pulls” objects toward each other  Law of universal gravitation= all objects in.

INSECTS AND HYDRODYNAMICS:

FLOW IN FLUIDIZED BEDS Fluidization refers to those gas-solids and liquid-solids system in which the solid phase is subjected to behave more or less like.

Mass Transfer transport of one constituent from a region of higher concentration to that of a lower concentration.

Reynolds Number (Re) Viscosity: resistance of a liquid to change of form. Inertia: resistance of an object (body) to a change in its state of motion.

Design of Port Injection Systems for SI Engines

10.5 Applications of the Idel Gas Equation

Environmental Engineering Lecture Note Week 11 (Transport Processes)

Aero/Hydrodynamic Properties

Air / Water Gas Exchange

Particle (s) motion.

Aero/Hydrodynamic Properties (Ch. 10)

Fundamentals of Convection

9th Lecture : Turbulence (II)

Convective Mass Transfer Coefficient

Mechanical Separation

Developing relationship between ACFM vs SCFM for HEPA Filters

Lecture 17 – Aero/Hydrodynamic Properties (Ch. 10)

Aero/Hydrodynamic Properties

SEDIMENTATION Aim - rapid removal of solid material by gravitational settling Drawbacks – colloidal material is slow settling Mustafa Nasser 2012.

SETTLING AND SEDIMENTATION.

Particle Collection Mechanisms

Presentation transcript:

Environmental Engineering Course Note 8 (Transport Processes II) Joonhong Park Yonsei CEE Department CEE3330 Y2013 WEEK3

CEE May 8, 2007 Joonhong Park Copy Right Transport Processes (II) 4.B Particle Motion – Drag on Particles – Gravitational Settling – Brownian Diffusion 4.C Mass Transfer at Fluid Boundaries – Mass-Transfer Coefficient – Transport across the Air-Water Interface

Size of environmental particles CEE May 8, 2007 Joonhong Park Copy Right Unit (micro meter) Aerosol Hydrosol Soil Microbial Fine mode Coarse mode Nucleation modeAccumulation mode Colloidal solidsSuspended solids Settleable solids Clay Silt Sand Virus Bacteria Algae

CEE May 8, 2007 Joonhong Park Copy Right Particle Motion Drag on Particle Gravitational Settling Brownian Diffusion

CEE May 8, 2007 Joonhong Park Copy Right Particle Motion Drag on Particle Drag Force Reynolds no. of particle

CEE May 8, 2007 Joonhong Park Copy Right Drag Coefficient (Cd) vs. Particlel Reynolds Number(Re p ) Re p Cd Stoke’s law Cd=24/Re Newton’s law Cd=0.445 Intermediate regime

CEE May 8, 2007 Joonhong Park Copy Right Fluid properties influencing drag force Stoke’s law (Re p < 0.3) Newton’s law (1000 < Re p < 350,000) Drag force is a function of viscosity Drag force is a function of fluid density

Correction for Small Particles (d p < 1µm) in air C c = Cunningham slip correction factor λ g = the mean free path (the average distance that a gas molecule travels before colliding with another molecule.) Ex. λ g = micrometer at 293 oK and 1 atm f = friction coefficient

CEE May 8, 2007 Joonhong Park Copy Right Gravitational Settling (a particle is denser than fluid) Terminal settling velocity (V t ) = satisfying

CEE May 8, 2007 Joonhong Park Copy Right Terminal settling velocity (V t ) = satisfying Gravitational Settling (a particle is lighter than fluid)

CEE May 8, 2007 Joonhong Park Copy Right Particle Motion Brownian Diffusion (following Fick’s 1 st Law) Diffusivity (Stoke-Einstein relation) k: Boltzmann’s constant T: absolute temp. f:fricktion coefficient

CEE May 8, 2007 Joonhong Park Copy Right Comparing Particle Transport by Settling and Diffusion micro-meter Traveling Distance (cm) Diffusion-air Diffusion-water x Settling-air Settling-water When a particle is lager than 1 micro-meter, settling becomes dominant

CEE May 8, 2007 Joonhong Park Copy Right Inter-phase Mass Transfer Phase 1 Boundary Layer Inter-phase Mass Transfer X-direction Y-direction Phase 2 CoCo C

CEE May 8, 2007 Joonhong Park Copy Right Mass-transfer coefficient

CEE May 8, 2007 Joonhong Park Copy Right Film Theory Ci C Well-mixed fluid Stagnant Fluid film Boundary Flux Lf

CEE May 8, 2007 Joonhong Park Copy Right Penetration Theory Ci C Well-mixed fluid Stagnant Fluid film Boundary Flux Lf t3 t2 t1 instantaneous

Water-Air Interface (Double-Layer Theory) Pi P Partial Pressure Turbulently mixed zone Stagnant film layer Boundary Flux La Stagnant film layer Turbulently mixed zone C Ci Lw Air Water

CEE May 8, 2007 Joonhong Park Copy Right

Reading Assignment Environmental Engineering & Sciences (EES) 4.B Particle Motion – Drag on Particles – Gravitational Settling – Brownian Diffusion 4.C Mass Transfer at Fluid Boundaries – Mass-Transfer Coefficient – Transport across the Air-Water Interface