Advanced Transport Phenomena Module 6 - Lecture 28
|
|
- Edward Cain
- 5 years ago
- Views:
Transcription
1 Mass Transport: Non-Ideal Flow Reactors Advanced Transport Phenomena Module 6 - Lecture 28 Dr. R. Nagarajan Professor Dept of Chemical Engineering IIT Madras 1
2 Simplest approach: apply overall material/ energy/ momentum balances to the reactor black box approach, insufficient Most rigorous: Divide into small subregions, approximate each region with PDEs Impractical Intermediate solution: model as discrete network of small number of interconnected ideal reactor types (SS PFR & WSR) 2
3 RTDF residence time distribution function (exit-age DF), E(t) E(t) dt fraction of material at vessel outlet stream that has been in vessel for times between t and t ± dt PFR: E(t) is a Dirac function, centered at residence time V/ m& / ρ ( ) 3
4 V vessel volume m& feed mass flow rate e.g., straight tube through which incompressible fluid flows with a uniform plug-flow velocity profile Partial recycle can alter RTDF 4
5 Tracer residence-time distribution functions for ideal and real vessels (for e.g., reactors) (adapted from Levenspiel (1972)) 5
6 Ideal plug-flow reactor (PFR) with partial recycle (recycle introduces a distribution of residence times, and reduces the residence time per pass within the PFR) 6
7 WSR: ( ) ( ) 1 E WSR = df/ dt= t exp flow t/ t flow Most likely residence time in a WSR is zero! Mean residence time = V/ m& / ρ ( ) Not all fluid parcels have same residence time, unlike PFR 7
8 WSR: Dimensionless variance s 2 about mean residence time indicator of spread of residence times Mean residence time related to first moment of E(t), i.e.: flow s 2 is related to 2 nd moment of E(t): σ t = 0 tet. () dt 2 1 ( ) ( ) 2 t t. () 2 flow Et dt= t E t dt t 2 flow tflow 0 tflow 0 = 1 for a WSR, 0 for a PFR 8 PFR with infinite recycle behaves like WSR
9 RTDF for Composite Systems: If RTDF for vessel 1 is E 1 (t) and for vessel 2 is E 2 (t), RTDF for a series combination of the two is: (convolution formula) t ( ) ( ) E + () t = E t. E t t dt ' ' ' 9
10 If vessel 1 is characterized by t flow,1, and s 12, and vessel 2 by t flow,2, and s 22, then for the series combination, mean residence times and variances are simply additive: t = t + t σ flow,1+ 2 flow,1 flow,2 = σ + σ
11 RTDF for Composite Systems: For a network of n-wsrs of equal volume, for which: (t flow 1 n 1 t t t flow E( n WSRs) =..exp ( n 1! ) tflow tflow V/( m& / ρ) ) for each vessel in series) 11
12 For vessels 1, 2, 3,., n in parallel, receiving fractions f 1, f 2, f 3,., f n of total flow: E= fe() t + f E() t f E () t n n Where i f = 1 i, and for each vessel: i 0 E t dt = 1 ( i= 1,2,..., n) ( ) 12
13 Real reactors as a network of ideal reactors: Modular modeling Network of ideal reactors can be constructed to approximate any experimental reactor RTDF: ωtracer() t Eexp() t = ωtracer ( t) dt 0 reactor exit (where tracer is input as a Dirac impulse function) 13
14 Real reactors as a network of ideal reactors: Modular modeling GT combustor; proposed interconnection of reactors comprising modular model (adapted from Swithenbank, et al.(1973)) 14
15 Real reactors as a network of ideal reactors: Modular modeling Info obtained from tracer diagnostics & from combustor geometry, cold-flow data, etc. Important since RTD-data alone cannot discriminate between alternative networks with identical RTDmoments t flow = te t dt, t E t dt,..., etc.) ( ) 2 ( )
16 Equivalent vessel network is nonunique Each alternative may capture one aspect (e.g., combustor efficiency) but not another (e.g., domain of stable operation) 16
17 Real reactors as a network of ideal reactors: Modular modeling Tracer methods can: Guide development of modular models Diagnose operating problems with existing chemical reactors or physical contactors RTD data can show up dead-volumes, flowchanneling, bypassing (all cause inefficient operation) Geometric or fluid-dynamic changes in design can correct these flaws Perturbation in feed can be used as tracer 17
18 Real reactors as a network of ideal reactors: Modular modeling RTD function, E(t), does not capture role of concentration fluctuations due to turbulence, incomplete mixing (at molecular level micromixing ) When tracer concentration fluctuates at reactor exit, we only collect data on <E(t)> arithmetic average of N tracer shots, each yielding RTD E j (t) (j = 1, 2,., N) 18
19 Two networks with identical <E(t)> but with different shot-to-shot variations, as measured by variance: lim 1 N N N j= 1 0 ( ) E t E() t dt j will perform differently as chemical reactors 2 19
20 Statistical micro flow (Random Eddy Surface-Renewal) models of interfacial mass transport in turbulent flow systems Mass/ energy transport visualized to occur during intervals of contact between turbulent eddies & surface stale eddies replaced by fresh ones Effective transport coefficient calculated by timeaveraging RTDF-weighted instantaneous St(t) 20
21 Statistical micro flow (Random Eddy Surface-Renewal) models of interfacial mass transport in turbulent flow systems If E(t) is defined such that: Relative portion of each unit interfacial area E() t dt covered by fluid eddies having"ages" between tandt+dt, 21
22 then: St = Stt (). Et () dt 0 St(t) calculated from transient micro fluid-dynamical analysis of individual eddy flow St time-averaged transfer coefficient Interfacial region being viewed as a thin vessel w.r.t eddy residence time 22
23 Statistical microflow (Random Eddy Surface-Renewal) models of interfacial mass transport in turbulent flow systems Earliest & simplest model: each eddy considered to behave like a translating solid body Large compared to transient diffusion BL (penetration) thickness Dimensional time-averaged mass-transfer coefficient given by: 23
24 4DA '' ja, m ( w πt = ρ ω ) Ab, ωaw, D A tm 1/2 1/2 [ ] fore( PFR) ( Higbie1935 [ ] for E( WSR) ( Danckwerts 1951) t m mean eddy contact time (1/(average renewal frequency)) Related to prevailing geometry & bulk-flow velocity Versatile alternative to Prandtl-Taylor eddy diffusivity approach 24
25 Extinction, ignition, parametric sensitivity of chemical reactors: Simplest modular model for steady-flow behavior of combustors: WSR + PFR 25
26 m& max upper limit to total mass flow rate, at each upstream condition (T u, p u, mixture ratio Φ) above which extinction of exoergic reaction (flame-out) abruptly occurs For m& < m& max m&,, two possible SS conditions exist: one corresponding to high fuel consumption & high temperature in WSR, the other to negligible fuel consumption & rise in T 26
27 Extinction, ignition, parametric sensitivity of chemical reactors: Simple, two-ideal reactor modular model of gas turbine, ramjet, or rocket engine combustor 27
28 Extinction, ignition, parametric sensitivity of chemical reactors: Parametric sensitivity: change in reactor performance for a small change in input or operating parameter (e.g., T u ) 28
29 Example: WSR module with following overall stoichiometric combustion reaction: 1gm O + f gmf 1+ f gram P+ fqcal(heat) ( ) 29
30 Extinction, ignition, parametric sensitivity of chemical reactors: Allow a 2 nd generation reactant (oxidant) & associated heat Governs WSR operating temperature, T 2 WSR species mass balance: (i = O, F, P) m&. r,, T. V ( ) ''' ω ( ) 2 ω 1 = & ω 2 ω 2 2 i i i O F WSR 30
31 Extinction, ignition, parametric sensitivity of chemical reactors: Overall energy balance: ( ) ''' = & ( ω ω ) mc &. T T r,, T QV. p 2 1 F O 2 F 2 WSR Source terms for oxidizer & fuel related by: r& = r& / f ''' O So, ω O 2 and ω F 2 can be expressed in terms of T 2 ''' F 31
32 Extinction, ignition, parametric sensitivity of chemical reactors: Overall kinetics represented by Arrhenius-type massaction rate law: ''' E 1 pm vo vf r& F = A.exp... ω vo vf 1 Oω F RT MOMF RT LHS straight line intersecting RHS at 3 distinct T 2 values, middle one unstable, upper ignited WSR SS, lower extinguished WSR SS (no chemical reaction) n 32
33 Extinction, ignition, parametric sensitivity of chemical reactors: Influence of feed mass flow rate on WSR operating temperature and space (volumetric heating rate(shr);(straight line is the LHS of the energy balance equation) 33
34 Extinction, ignition, parametric sensitivity of chemical reactors: Maximum volumetric rate of fuel consumption (hence, maximum chemical heating rate) occurs at WSR temperature: T ''' r& Tb max 1 + n( RT / E) Only slightly > extinction temperature (previous Figure) T b adiabatic, complete-combustion temperature Typical E, n values listed in following Table b 34
35 Extinction, ignition, parametric sensitivity of chemical reactors: a Supplemented, rounded (and selected) values based on Table 4.4 of Kanury (1975) b Units are: s -1 (g-moles/cm 3 ) -(n-1 ), where n is the overall reaction order. c units are: 109 BTU/ft 3 /hr d Stoichiometric mixture, no diluent ( diluent is N 2 ) unless otherwise specified 35
36 Extinction, ignition, parametric sensitivity of chemical reactors: Black-box modular-models capture many important features of real reactors, useful for correlating performance data on full-scale & small-scale models Predictive ability limited compared to more-detailed pseudo-continuum mathematical models All have, as their basis, macroscopic conservation principles outlined earlier in this course. 36
37 PROBLEM1 The length requirement for a honeycomb-type automotive exhaust catalytic converter is set by the need to reduce the CO concentration in the exhaust to about 5% of the inlet concentration (i.e., 95% conversion). Consider the basic conditions: Inlet gas temperature 700K Inlet gas pressure 1 atm Inlet gas composition y(n 2 )=0.93, y(co)=0.02, (mole fraction) y(o 2 )=
38 PROBLEM1 Inlet gas velocity 10 3 cm/s Channel cross-section dimensions 1.5mm by 1.5mm (each channel) Assumed channel wall temperature 500 K Assume that the Pt-based catalyst used on the walls of each channel is active enough to cause the surfacecatalyzed CO oxidation reaction to be diffusion-controlled, that is, the steady-state value of the CO-mass fraction established at (1 mean-free-path away from) 38
39 PROBLEM1 the wall, ω CO,w, is negligible compared to ω CO,b (z) within each channel. Also assume that the gas-phase kinetics of CO oxidation under these conditions preclude appreciable (uncatalyzed) homogeneous COassumption in the available residence times. Answer the following questions: a. By what mechanism is CO(g) mass transported to the channel wall, where chemical consumption (to produce CO 2 ) occurs? What is the relevant transport coefficient 39
40 PROBLEM1 and to what energy-transfer process and transport properly coefficient is this analogous? b. Are the mass-heat transfer analogy conditions (MAC, HAC) discussed in this module approximately met in this application? What is the inlet mass fraction of CO gas? Sc v D / CO mix c. Estimate the Schmidt number mix for CO Fick diffusion through the prevailing combustion gas mixture, using the experimental observation that 40
41 PROBLEM1 D CO N T cm. p 300 s where p is the prevailing pressure (expressed in atmospheres) and T the mixture temperature (expressed in kelvins) d. Under the flow rate, temperature, and pressure conditions given above and using the mass-transfer analog, estimate the catalytic duct length 41
42 PROBLEM1 required to consume 95% of the inlet CO concentration, and the mixing cup (bulk) stream temperature at this length. e. List and defend the principal assumptions made in arriving at the length estimate (of Part (d)) f. If the catalyst were poisoned (e.g., by lead compounds), what could happen to the CO exit concentration? Which of the assumptions used in predicting the required converter length (Part (d)) would be violated? 42
43 PROBLEM1 g. If the heat of combustion of CO(g) is about 67.8 kcal/gmole CO consumed, calculate how much must be removed to maintain the channel-wall temperature constant at 500 K? h. Automatic operating conditions are never strictly steady, so that in practice the mass-flow rate, temperature, and gas composition entering the catalytic afterburner will be time-dependent. Under what circumstances (be 43
44 PROBLEM1 quantitative) can the design equations you used be defended if used to predict the conditions exiting the duct at each instant?(quasi-steady approximation) i. At the design condition, estimate the fractional pressure drop, p/ p 0, in the honeycomb-type catalytic afterburner. If, instead of the honeycomb type converter, a packed bed device were used to achieve the same reduction in CO-concentration, would you expect p/ p to be larger or smaller than the honeycomb device of your preliminary design? 0 44
Nirma University Institute of Technology Chemical Engineering Department, Handouts -RRP- CRE-II. Handouts
Handouts Handout 1: Practical reactor performance deviates from that of ideal reactor s : Packed bed reactor Channeling CSTR & Batch Dead Zones, Bypass PFR deviation from plug flow dispersion Deviation
More informationChemical Reaction Engineering - Part 16 - more reactors Richard K. Herz,
Chemical Reaction Engineering - Part 16 - more reactors Richard K. Herz, rherz@ucsd.edu, www.reactorlab.net More reactors So far we have learned about the three basic types of reactors: Batch, PFR, CSTR.
More informationA First Course on Kinetics and Reaction Engineering Unit 33. Axial Dispersion Model
Unit 33. Axial Dispersion Model Overview In the plug flow reactor model, concentration only varies in the axial direction, and the sole causes of that variation are convection and reaction. Unit 33 describes
More informationChemical Reaction Engineering
Lecture 32! Chemical Reaction Engineering (CRE) is the field that studies the rates and mechanisms of chemical reactions and the design of the reactors in which they take place.!! 1! Lecture 32 Thursday
More informationChemical Reactions and Chemical Reactors
Chemical Reactions and Chemical Reactors George W. Roberts North Carolina State University Department of Chemical and Biomolecular Engineering WILEY John Wiley & Sons, Inc. x Contents 1. Reactions and
More informationNon-Ideal Reactors. Definitions * Segregated flow - fluid elements do not mix, have different residence times - Need Residence Time Distribution
Non-Ideal Reactors Deviations from ideal reactor behavior - Tank Reactors: inadequate mixing, stagnant regions, bypassing or short-circuiting Tubular Reactors: mixing in longitudinal direction, incomplete
More informationTABLE OF CONTENT. Chapter 4 Multiple Reaction Systems 61 Parallel Reactions 61 Quantitative Treatment of Product Distribution 63 Series Reactions 65
TABLE OF CONTENT Chapter 1 Introduction 1 Chemical Reaction 2 Classification of Chemical Reaction 2 Chemical Equation 4 Rate of Chemical Reaction 5 Kinetic Models For Non Elementary Reaction 6 Molecularity
More informationINTRODUCTION TO CATALYTIC COMBUSTION
INTRODUCTION TO CATALYTIC COMBUSTION R.E. Hayes Professor of Chemical Engineering Department of Chemical and Materials Engineering University of Alberta, Canada and S.T. Kolaczkowski Professor of Chemical
More informationReview: Nonideal Flow in a CSTR
L3- Review: Nonideal Flow in a CSTR Ideal CSTR: uniform reactant concentration throughout the vessel Real stirred tank Relatively high reactant concentration at the feed entrance Relatively low concentration
More informationContents. Preface... xvii
Contents Preface... xvii CHAPTER 1 Idealized Flow Machines...1 1.1 Conservation Equations... 1 1.1.1 Conservation of mass... 2 1.1.2 Conservation of momentum... 3 1.1.3 Conservation of energy... 3 1.2
More informationNPTEL. Chemical Reaction Engineering II - Video course. Chemical Engineering. COURSE OUTLINE
NPTEL Syllabus Chemical Reaction Engineering II - Video course COURSE OUTLINE This is a typical second course in the subject of chemical reaction engineering with an emphasis on heterogeneous reaction
More informationInteractions between oxygen permeation and homogeneous-phase fuel conversion on the sweep side of an ion transport membrane
Interactions between oxygen permeation and homogeneous-phase fuel conversion on the sweep side of an ion transport membrane The MIT Faculty has made this article openly available. Please share how this
More informationWell Stirred Reactor Stabilization of flames
Well Stirred Reactor Stabilization of flames Well Stirred Reactor (see books on Combustion ) Stabilization of flames in high speed flows (see books on Combustion ) Stabilization of flames Although the
More informationChE 344 Winter 2013 Mid Term Exam II Tuesday, April 9, 2013
ChE 344 Winter 2013 Mid Term Exam II Tuesday, April 9, 2013 Open Course Textbook Only Closed everything else (i.e., Notes, In-Class Problems and Home Problems Name Honor Code (Please sign in the space
More informationHydrogen addition to the Andrussow process for HCN synthesis
Applied Catalysis A: General 201 (2000) 13 22 Hydrogen addition to the Andrussow process for HCN synthesis A.S. Bodke, D.A. Olschki, L.D. Schmidt Department of Chemical Engineering and Materials Science,
More informationSteady-State Molecular Diffusion
Steady-State Molecular Diffusion This part is an application to the general differential equation of mass transfer. The objective is to solve the differential equation of mass transfer under steady state
More informationξ Da nc n = c Pe ξ = c o ( θ ) (95) c ξ = 0 (96) θ = 0 ; c= c i ξ ( ) (97) (98) Pe z = u L E z
5. THE AXIAL DISPERSION MODEL The axial dispersion model can readily be extended to apply to turbulent flow conditions. Under such conditions the velocity profile is almost flat and averaging with respect
More informationModels for Nonideal Reactors
Fogler_Web_Ch18.fm Page 1 Monday, October 9, 017 1:58 PM Models for Nonideal Reactors 18 Success is a journey, not a destination. Ben Sweetland Use the RTD to evaluate parameters. Overview. Not all tank
More informationAUTOMOTIVE EXHAUST AFTERTREATMENT
AUTOMOTIVE EXHAUST AFTERTREATMENT CATALYST FUNDAMENTLS Catalyst in its simplest term is a material that increase the rate (molecules converted by unit time) of a chemical reaction while itself not undergoing
More informationCHAPTER 4 EXPERIMENTAL METHODS
47 CHAPTER 4 EXPERIMENTAL METHODS 4.1 INTRODUCTION The experimental procedures employed in the present work are oriented towards the evaluation of residence time distribution in a static mixer and the
More information1. Introductory Material
CHEE 321: Chemical Reaction Engineering 1. Introductory Material 1b. The General Mole Balance Equation (GMBE) and Ideal Reactors (Fogler Chapter 1) Recap: Module 1a System with Rxn: use mole balances Input
More informationChemical Reaction Engineering Prof. Jayant Modak Department of Chemical Engineering Indian Institute of Science, Bangalore
Chemical Reaction Engineering Prof. Jayant Modak Department of Chemical Engineering Indian Institute of Science, Bangalore Lecture No. #40 Problem solving: Reactor Design Friends, this is our last session
More informationChemical Reaction Engineering
Chemical Reaction Engineering Dr. Yahia Alhamed Chemical and Materials Engineering Department College of Engineering King Abdulaziz University General Mole Balance Batch Reactor Mole Balance Constantly
More informationINTRODUCTION TO CHEMICAL PROCESS SIMULATORS
INTRODUCTION TO CHEMICAL PROCESS SIMULATORS DWSIM Chemical Process Simulator A. Carrero, N. Quirante, J. Javaloyes October 2016 Introduction to Chemical Process Simulators Contents Monday, October 3 rd
More informationBasic Concepts in Reactor Design
Basic Concepts in Reactor Design Lecture # 01 KBK (ChE) Ch. 8 1 / 32 Introduction Objectives Learning Objectives 1 Different types of reactors 2 Fundamental concepts used in reactor design 3 Design equations
More informationChE 344 Winter 2013 Mid Term Exam I Tuesday, February 26, Closed Book, Web, and Notes. Honor Code
ChE 344 Winter 2013 Mid Term Exam I Tuesday, February 26, 2013 Closed Book, Web, and Notes Name Honor Code (Sign at the end of exam period) 1) / 5 pts 2) / 5 pts 3) / 5 pts 4) / 5 pts 5) / 5 pts 6) / 5
More informationLecture (9) Reactor Sizing. Figure (1). Information needed to predict what a reactor can do.
Lecture (9) Reactor Sizing 1.Introduction Chemical kinetics is the study of chemical reaction rates and reaction mechanisms. The study of chemical reaction engineering (CRE) combines the study of chemical
More informationLarge-eddy simulation of an industrial furnace with a cross-flow-jet combustion system
Center for Turbulence Research Annual Research Briefs 2007 231 Large-eddy simulation of an industrial furnace with a cross-flow-jet combustion system By L. Wang AND H. Pitsch 1. Motivation and objectives
More informationModel for Steam Reforming of Ethanol Using a Catalytic Wall Reactor
Excerpt from the Proceedings of the COMSOL Conference 28 Hannover Model for Steam Reforming of Ethanol Using a Catalytic Wall Reactor J.A. Torres *1 and D. Montané 2 1 Centre Huile Lourde Ouvert et Expérimental
More informationA First Course on Kinetics and Reaction Engineering Unit D and 3-D Tubular Reactor Models
Unit 34. 2-D and 3-D Tubular Reactor Models Overview Unit 34 describes two- and three-dimensional models for tubular reactors. One limitation of the ideal PFR model is that the temperature and composition
More informationEngineering and. Tapio Salmi Abo Akademi Abo-Turku, Finland. Jyri-Pekka Mikkola. Umea University, Umea, Sweden. Johan Warna.
Chemical Reaction Engineering and Reactor Technology Tapio Salmi Abo Akademi Abo-Turku, Finland Jyri-Pekka Mikkola Umea University, Umea, Sweden Johan Warna Abo Akademi Abo-Turku, Finland CRC Press is
More informationA First Course on Kinetics and Reaction Engineering Example 11.5
Example 11.5 Problem Purpose This problem illustrates the use of the age function measured using a step change stimulus to test whether a reactor conforms to the assumptions of the ideal PFR model. Then
More informationCHEMICAL REACTORS - PROBLEMS OF NON IDEAL REACTORS 61-78
011-01 ourse HEMIL RETORS - PROBLEMS OF NON IDEL RETORS 61-78 61.- ccording to several experiments carried out in a continuous stirred tank reactor we suspect that the behavior of the reactor is not ideal.
More informationLecture 8 Laminar Diffusion Flames: Diffusion Flamelet Theory
Lecture 8 Laminar Diffusion Flames: Diffusion Flamelet Theory 8.-1 Systems, where fuel and oxidizer enter separately into the combustion chamber. Mixing takes place by convection and diffusion. Only where
More informationProcess Chemistry Toolbox - Mixing
Process Chemistry Toolbox - Mixing Industrial diffusion flames are turbulent Laminar Turbulent 3 T s of combustion Time Temperature Turbulence Visualization of Laminar and Turbulent flow http://www.youtube.com/watch?v=kqqtob30jws
More informationLaminar Premixed Flames: Flame Structure
Laminar Premixed Flames: Flame Structure Combustion Summer School 2018 Prof. Dr.-Ing. Heinz Pitsch Course Overview Part I: Fundamentals and Laminar Flames Introduction Fundamentals and mass balances of
More informationThermoacoustic Instabilities Research
Chapter 3 Thermoacoustic Instabilities Research In this chapter, relevant literature survey of thermoacoustic instabilities research is included. An introduction to the phenomena of thermoacoustic instability
More informationH 0 r = -18,000 K cal/k mole Assume specific heats of all solutions are equal to that of water. [10]
Code No: RR320802 Set No. 1 III B.Tech II Semester Supplementary Examinations, November/December 2005 CHEMICAL REACTION ENGINEERING-I (Chemical Engineering) Time: 3 hours Max Marks: 80 Answer any FIVE
More informationModels for Nonideal Reactors
Fogler_ECRE_CDROM.book Page 945 Wednesday, September 17, 8 5:1 PM Models for Nonideal Reactors 14 Success is a journey, not a destination. Ben Sweetland Use the RTD to evaluate parameters Overview Not
More informationSolutions for Tutorial 5 Dynamic Behavior of Typical Dynamic Systems
olutions for Tutorial 5 Dynamic Behavior of Typical Dynamic ystems 5.1 First order ystem: A model for a first order system is given in the following equation. dy dt X in X out (5.1.1) What conditions have
More informationExtinction Limits of Premixed Combustion Assisted by Catalytic Reaction in a Stagnation-Point Flow
44th AIAA Aerospace Sciences Meeting and Exhibit 9-12 January 2006, Reno, Nevada AIAA 2006-164 Extinction Limits of Premixed Combustion Assisted by Catalytic Reaction in a Stagnation-Point Flow Jingjing
More informationChapter 8 STATISTICAL ASSESSMENT OF NUMERICAL DIFFUSION
84 hapter 8 STATISTIAL ASSESSMENT OF NUMERIAL DIFFUSION The assessment of the performance of high-order numerical methods regarding the numerical diffusion introduced in the solution of the scalar transport
More informationDARS overview, IISc Bangalore 18/03/2014
www.cd-adapco.com CH2O Temperatur e Air C2H4 Air DARS overview, IISc Bangalore 18/03/2014 Outline Introduction Modeling reactions in CFD CFD to DARS Introduction to DARS DARS capabilities and applications
More informationThe Effect of Mixture Fraction on Edge Flame Propagation Speed
8 th U. S. National Combustion Meeting Organized by the Western States Section of the Combustion Institute and hosted by the University of Utah May 19-22, 213 The Effect of Mixture Fraction on Edge Flame
More informationStudy on residence time distribution of CSTR using CFD
Indian Journal of Chemical Technology Vol. 3, March 16, pp. 114-1 Study on residence time distribution of CSTR using CFD Akhilesh Khapre*, Divya Rajavathsavai & Basudeb Munshi Department of Chemical Engineering,
More informationChemical Reaction Engineering. Dr. Yahia Alhamed
Chemical Reaction Engineering Dr. Yahia Alhamed 1 Kinetics and Reaction Rate What is reaction rate? It is the rate at which a species looses its chemical identity per unit volume. The rate of a reaction
More informationMidterm II. ChE 142 April 11, (Closed Book and notes, two 8.5 x11 sheet of notes is allowed) Printed Name
ChE 142 pril 11, 25 Midterm II (Closed Book and notes, two 8.5 x11 sheet of notes is allowed) Printed Name KEY By signing this sheet, you agree to adhere to the U.C. Berkeley Honor Code Signed Name_ KEY
More informationModule 1: Mole Balances, Conversion & Reactor Sizing (Chapters 1 and 2, Fogler)
CHE 309: Chemical Reaction Engineering Lecture-2 Module 1: Mole Balances, Conversion & Reactor Sizing (Chapters 1 and 2, Fogler) Module 1: Mole Balances, Conversion & Reactor Sizing Topics to be covered
More informationBASIC DESIGN EQUATIONS FOR MULTIPHASE REACTORS
BASIC DESIGN EQUATIONS FOR MULTIPHASE REACTORS Starting Reference 1. P. A. Ramachandran and R. V. Chaudhari, Three-Phase Catalytic Reactors, Gordon and Breach Publishers, New York, (1983). 2. Nigam, K.D.P.
More informationSection 4.1: Introduction to Jet Propulsion. MAE Propulsion Systems II
Section 4.1: Introduction to Jet Propulsion Jet Propulsion Basics Squeeze Bang Blow Suck Credit: USAF Test Pilot School 2 Basic Types of Jet Engines Ramjet High Speed, Supersonic Propulsion, Passive Compression/Expansion
More informationChE 344 Winter 2011 Mid Term Exam I + Solution. Closed Book, Web, and Notes
ChE 344 Winter 011 Mid Term Exam I + Thursday, February 17, 011 Closed Book, Web, and Notes Name Honor Code (sign at the end of exam) 1) / 5 pts ) / 5 pts 3) / 5 pts 4) / 15 pts 5) / 5 pts 6) / 5 pts 7)
More informationMethane Oxidation Reactions
Methane Oxidation Reactions CH 4 + 2 O -> CO 2 2 + 2 H 2 O Total Oxidation (Combustion) CH 4 + 0.5 O -> CO 2 + 2 H 2 CO + 0.5 O -> CO 2 2 H 2 + 0.5 O -> H 2 2 O CH 4 + H 2 O->CO + 3 H 2 Partial Oxidation
More informationEffect of Shape and Flow Control Devices on the Fluid Flow Characteristics in Three Different Industrial Six Strand Billet Caster Tundish
, pp. 1647 1656 Effect of Shape and Flow Control Devices on the Fluid Flow Characteristics in Three Different Industrial Six Strand Billet Caster Tundish Anurag TRIPATHI and Satish Kumar AJMANI Research
More informationHeat-recirculating combustors. Paul D. Ronney
Heat-recirculating combustors Paul D. Ronney Department of Aerospace and Mechanical Engineering, 3650 McClintock Ave., OHE 430J University of Southern California, Los Angeles, CA, USA 90089-1453 1-213-740-0490
More informationThermodynamics ENGR360-MEP112 LECTURE 7
Thermodynamics ENGR360-MEP11 LECTURE 7 Thermodynamics ENGR360/MEP11 Objectives: 1. Conservation of mass principle.. Conservation of energy principle applied to control volumes (first law of thermodynamics).
More informationApplied Gas Dynamics Flow With Friction and Heat Transfer
Applied Gas Dynamics Flow With Friction and Heat Transfer Ethirajan Rathakrishnan Applied Gas Dynamics, John Wiley & Sons (Asia) Pte Ltd c 2010 Ethirajan Rathakrishnan 1 / 121 Introduction So far, we have
More informationBest Practice Guidelines for Combustion Modeling. Raphael David A. Bacchi, ESSS
Best Practice Guidelines for Combustion Modeling Raphael David A. Bacchi, ESSS PRESENTATION TOPICS Introduction; Combustion Phenomenology; Combustion Modeling; Reaction Mechanism; Radiation; Case Studies;
More informationMass Transfer Operations I Prof. Bishnupada Mandal Department of Chemical Engineering Indian Institute of Technology, Guwahati
Mass Transfer Operations I Prof. Bishnupada Mandal Department of Chemical Engineering Indian Institute of Technology, Guwahati Module - 2 Mass Transfer Coefficient Lecture - 4 Boundary Layer Theory and
More informationThe distortion observed in the bottom channel of Figure 1 can be predicted from the full transport equation, C t + u C. y D C. z, (1) x D C.
1 8. Shear Dispersion. The transport models and concentration field solutions developed in previous sections assume that currents are spatially uniform, i.e. u f(,y,). However, spatial gradients of velocity,
More informationA First Course on Kinetics and Reaction Engineering Unit 30.Thermal Back-Mixing in a PFR
Unit 30.Thermal Back-Mixing in a PFR Overview One advantage offered by a CSTR when running an exothermic reaction is that the cool feed gets heated by mixing with the contents of the reactor. As a consequence
More informationENZYME SCIENCE AND ENGINEERING PROF. SUBHASH CHAND DEPARTMENT OF BIOCHEMICAL ENGINEERING AND BIOTECHNOLOGY IIT DELHI
ENZYME SCIENCE AND ENGINEERING PROF. SUBHASH CHAND DEPARTMENT OF BIOCHEMICAL ENGINEERING AND BIOTECHNOLOGY IIT DELHI LECTURE 23 STEADY STATE ANALYSIS OF MASS TRANSFER & BIOCHEMICAL REACTION IN IME REACTORS
More informationComputer Fluid Dynamics E181107
Computer Fluid Dynamics E181107 2181106 Combustion, multiphase flows Remark: foils with black background could be skipped, they are aimed to the more advanced courses Rudolf Žitný, Ústav procesní a zpracovatelské
More informationDARS Digital Analysis of Reactive Systems
DARS Digital Analysis of Reactive Systems Introduction DARS is a complex chemical reaction analysis system, developed by DigAnaRS. Our latest version, DARS V2.0, was released in September 2008 and new
More informationCONTENTS Real chemistry e ects Scramjet operating envelope Problems
Contents 1 Propulsion Thermodynamics 1-1 1.1 Introduction.................................... 1-1 1.2 Thermodynamic cycles.............................. 1-8 1.2.1 The Carnot cycle.............................
More informationJet Aircraft Propulsion Prof. Bhaskar Roy Prof. A.M. Pradeep Department of Aerospace Engineering
Jet Aircraft Propulsion Prof. Bhaskar Roy Prof. A.M. Pradeep Department of Aerospace Engineering Indian Institute of Technology, IIT Bombay Module No. # 01 Lecture No. # 08 Cycle Components and Component
More informationBasics of Non-Ideal Flow
Chapter 11 Basics of Non-Ideal Flow So far we have treated two flow patterns, plug flow and mixed flow. These can give very different behavior (size of reactor, distribution of products). We like these
More informationReaction and Diffusion in a Porous Catalyst Pellet. by Richard K. Herz
Reaction and Diffusion in a Porous Catalyst Pellet by Richard K. Herz Solid catalysts are often called "heterogeneous catalysts" meaning that they are in a different phase from fluid reactants
More informationModeling of Packed Bed Reactors: Hydrogen Production by the Steam Reforming of Methane and Glycerol
Modeling of Packed Bed Reactors: Hydrogen Production by the Steam Reforming of Methane and Glycerol A. G. Dixon *,1, B. MacDonald 1, A. Olm 1 1 Department of Chemical Engineering, Worcester Polytechnic
More informationChE 344 Winter 2013 Final Exam + Solution. Open Course Textbook Only Closed everything else (i.e., Notes, In-Class Problems and Home Problems
ChE 344 Winter 03 Final Exam + Solution Thursday, May, 03 Open Course Textbook Only Closed everything else (i.e., Notes, In-Class Problems and Home Problems Name Honor Code (Please sign in the space provided
More informationOverview of Turbulent Reacting Flows
Overview of Turbulent Reacting Flows Outline Various Applications Overview of available reacting flow models LES Latest additions Example Cases Summary Reacting Flows Applications in STAR-CCM+ Ever-Expanding
More informationADVANCED DES SIMULATIONS OF OXY-GAS BURNER LOCATED INTO MODEL OF REAL MELTING CHAMBER
ADVANCED DES SIMULATIONS OF OXY-GAS BURNER LOCATED INTO MODEL OF REAL MELTING CHAMBER Ing. Vojtech Betak Ph.D. Aerospace Research and Test Establishment Department of Engines Prague, Czech Republic Abstract
More information5. Coupling of Chemical Kinetics & Thermodynamics
5. Coupling of Chemical Kinetics & Thermodynamics Objectives of this section: Thermodynamics: Initial and final states are considered: - Adiabatic flame temperature - Equilibrium composition of products
More informationThermochemistry X.S. Bai Thermochemistry
Lecture 2 Thermochemistry Design a power plant X.S. Bai Thermochemistry When we study a combustion device, what do we want to know? heat generated power production combustion efficiency combustion control
More informationA new jet-stirred reactor for chemical kinetics investigations Abbasali A. Davani 1*, Paul D. Ronney 1 1 University of Southern California
0 th U. S. National Combustion Meeting Organized by the Eastern States Section of the Combustion Institute pril 23-26, 207 College Park, Maryland new jet-stirred reactor for chemical kinetics investigations
More informationProcess Design Decisions and Project Economics Prof. Dr. V. S. Moholkar Department of Chemical Engineering Indian Institute of Technology, Guwahati
Process Design Decisions and Project Economics Prof. Dr. V. S. Moholkar Department of Chemical Engineering Indian Institute of Technology, Guwahati Module - 2 Flowsheet Synthesis (Conceptual Design of
More informationChemical Reaction Engineering Prof. JayantModak Department of Chemical Engineering Indian Institute of Science, Bangalore
Chemical Reaction Engineering Prof. JayantModak Department of Chemical Engineering Indian Institute of Science, Bangalore Module No. #05 Lecture No. #29 Non Isothermal Reactor Operation Let us continue
More informationLecture 6 Asymptotic Structure for Four-Step Premixed Stoichiometric Methane Flames
Lecture 6 Asymptotic Structure for Four-Step Premixed Stoichiometric Methane Flames 6.-1 Previous lecture: Asymptotic description of premixed flames based on an assumed one-step reaction. basic understanding
More informationBAE 820 Physical Principles of Environmental Systems
BAE 820 Physical Principles of Environmental Systems Type of reactors Dr. Zifei Liu Ideal reactors A reactor is an apparatus in which chemical, biological, and physical processes (reactions) proceed intentionally,
More informationErratum to: High speed mixture fraction and temperature imaging of pulsed, turbulent fuel jets auto igniting in high temperature, vitiated co flows
DOI 10.1007/s00348-015-2101-9 ERRATUM Erratum to: High speed mixture fraction and temperature imaging of pulsed, turbulent fuel jets auto igniting in high temperature, vitiated co flows Michael J. Papageorge
More informationReactors. Reaction Classifications
Reactors Reactions are usually the heart of the chemical processes in which relatively cheap raw materials are converted to more economically favorable products. In other cases, reactions play essential
More informationConvective Mass Transfer
Convective Mass Transfer Definition of convective mass transfer: The transport of material between a boundary surface and a moving fluid or between two immiscible moving fluids separated by a mobile interface
More informationMASS, MOMENTUM, AND ENERGY EQUATIONS
MASS, MOMENTUM, AND ENERGY EQUATIONS This chapter deals with four equations commonly used in fluid mechanics: the mass, Bernoulli, Momentum and energy equations. The mass equation is an expression of the
More informationBAE 820 Physical Principles of Environmental Systems
BAE 820 Physical Principles of Environmental Systems Catalysis of environmental reactions Dr. Zifei Liu Catalysis and catalysts Catalysis is the increase in the rate of a chemical reaction due to the participation
More informationIDEAL REACTORS FOR HOMOGENOUS REACTION AND THEIR PERFORMANCE EQUATIONS
IDEAL REACTORS FOR HOMOGENOUS REACTION AND THEIR PERFORMANCE EQUATIONS At the end of this week s lecture, students should be able to: Differentiate between the three ideal reactors Develop and apply the
More informationNPTEL. Chemical Reaction Engineering 1 (Homogeneous Reactors) - Video course. Chemical Engineering.
NPTEL Syllabus Chemical Reaction Engineering 1 (Homogeneous Reactors) - Video course COURSE OUTLINE In simple terms, Chemical Engineering deals with the production of a variety of chemicals on large scale.
More informationMODELING OF CONTINUOUS OSCILLATORY BAFFLED REACTOR FOR BIODIESEL PRODUCTION FROM JATROPHA OIL ABSTRACT
MODELING OF CONTINUOUS OSCILLATORY BAFFLED REACTOR FOR BIODIESEL PRODUCTION FROM JATROPHA OIL B. K. Highina, I. M. Bugaje & B. Gutti Department of Chemical Engineering University of Maiduguri, Borno State,
More informationCFD Simulation of Internal Flowfield of Dual-mode Scramjet
CFD Simulation of Internal Flowfield of Dual-mode Scramjet C. Butcher, K. Yu Department of Aerospace Engineering, University of Maryland, College Park, MD, USA Abstract: The internal flowfield of a hypersonic
More informationTURBINE BURNERS: Engine Performance Improvements; Mixing, Ignition, and Flame-Holding in High Acceleration Flows
TURBINE BURNERS: Engine Performance Improvements; Mixing, Ignition, and Flame-Holding in High Acceleration Flows Presented by William A. Sirignano Mechanical and Aerospace Engineering University of California
More informationJet Aircraft Propulsion Prof. Bhaskar Roy Prof A M Pradeep Department of Aerospace Engineering Indian Institute of Technology, Bombay
Jet Aircraft Propulsion Prof. Bhaskar Roy Prof A M Pradeep Department of Aerospace Engineering Indian Institute of Technology, Bombay Module No. #01 Lecture No. # 07 Jet Engine Cycles For Aircraft propulsion
More informationChemical Reaction Engineering. Multiple Reactions. Dr.-Eng. Zayed Al-Hamamre
Chemical Reaction Engineering Multiple Reactions Dr.-Eng. Zayed Al-Hamamre 1 Content Types of Reactions Selectivity Reaction Yield Parallel Reactions Series Reactions Net Rates of Reaction Complex Reactions
More informationHeat and Mass Transfer Prof. S.P. Sukhatme Department of Mechanical Engineering Indian Institute of Technology, Bombay
Heat and Mass Transfer Prof. S.P. Sukhatme Department of Mechanical Engineering Indian Institute of Technology, Bombay Lecture No. 18 Forced Convection-1 Welcome. We now begin our study of forced convection
More information7.2 Sublimation. The following assumptions are made in order to solve the problem: Sublimation Over a Flat Plate in a Parallel Flow
7..1 Sublimation Over a Flat Plate in a Parallel Flow The following assumptions are made in order to solve the problem: 1.. 3. The flat plate is very thin and so the thermal resistance along the flat plate
More informationA First Course on Kinetics and Reaction Engineering. Class 20 on Unit 19
A First Course on Kinetics and Reaction Engineering Class 20 on Unit 19 Part I - Chemical Reactions Part II - Chemical Reaction Kinetics Where We re Going Part III - Chemical Reaction Engineering A. Ideal
More informationBAE 820 Physical Principles of Environmental Systems
BAE 820 Physical Principles of Environmental Systems Inter phase mass transfer Dr. Zifei Liu Mass transfer between two phases For a two phase system not at equilibrium (concentrations in the two phases
More informationA comparison between two different Flamelet reduced order manifolds for non-premixed turbulent flames
8 th U. S. National Combustion Meeting Organized by the Western States Section of the Combustion Institute and hosted by the University of Utah May 19-22, 2013 A comparison between two different Flamelet
More informationMass Transfer Operations I Prof. Bishnupada Mandal Department of Chemical Engineering Indian Institute of Technology, Guwahati
Mass Transfer Operations I Prof. Bishnupada Mandal Department of Chemical Engineering Indian Institute of Technology, Guwahati Module - 4 Absorption Lecture - 4 Packed Tower Design Part - 3 Welcome to
More informationThermodynamic and Stochiometric Principles in Materials Balance
Thermodynamic and Stochiometric Principles in Materials Balance Typical metallurgical engineering problems based on materials and energy balance NiO is reduced in an open atmosphere furnace by excess carbon
More information5/6/ :41 PM. Chapter 6. Using Entropy. Dr. Mohammad Abuhaiba, PE
Chapter 6 Using Entropy 1 2 Chapter Objective Means are introduced for analyzing systems from the 2 nd law perspective as they undergo processes that are not necessarily cycles. Objective: introduce entropy
More informationEngineering. Green Chemical. S. Suresh and S. Sundaramoorthy. and Chemical Processes. An Introduction to Catalysis, Kinetics, CRC Press
I i Green Chemical Engineering An Introduction to Catalysis, Kinetics, and Chemical Processes S. Suresh and S. Sundaramoorthy CRC Press Taylor & Francis Group Boca Raton London New York CRC Press is an
More informationIntroduction to the course ``Theory and Development of Reactive Systems'' (Chemical Reaction Engineering - I)
Introduction to the course ``Theory and Development of Reactive Systems'' (Chemical Reaction Engineering - I) Prof. Gabriele Pannocchia Department of Civil and Industrial Engineering (DICI) University
More information