modeling simulation lecture1

11/8/2020

1

Ali M. Sahlodin

Department of Chemical Engineering

AmirKabir University of Technology

Fall 1398 S.H

� Ali M. Sahlodin )علی محمد سهل الدین(� BSc in Chem. Eng., University of Tehran (1384).

� MSc in Simulation and Control, Sharif University of Technology (1386).

� PhD in Process Optimization, McMaster University (1391).

� Postdoc in Dynamic Optimization, Massachusetts Institute of Technology (1392-1394).

� Sr Engineer, Aspen Technology (1394-1397).

2Copyright © Ali M. Sahlodin, Dept. of Chemical Engineering, AmirKabir Univ. of Tech.

Office location: 4th floor

Email: [email protected]

11/8/2020

2

� Your name

� Your background

� Your current concentration

� What do you expect from this course?


My way of communication with you:•Class announcements•Email (your official AUT email, so please check regularly!)

� Lectures

� Powerpoint slides/chalkboard/whiteboard

� Slides available on LMS.

� Use of Software as appropriate

� Octave, COCO, DWSIM, etc

� Class discussions


11/8/2020

3

� Assignments (50%)

� Done individually

� Project (30%)

� Groups of two or three

� Members’ contributions must be clearly specified.

� Report and oral presentation

� Final (20%)

5

Working with software like Octave, MATLAB, or similar

may be required.

Copyright © Ali M. Sahlodin, Dept. of Chemical Engineering, AmirKabir Univ. of Tech.

� Attendance required.

� Attention requested.

� Questions may be asked at any time.

� Remember: no question is naïve!

� Assignments

� Late assignments may be penalized.

� Too late submission will NOT be accepted.

� Assignments must be submitted in a single PDF via LMS (no hardcopy)

Email only if LMS closed (include student # in subject line)


11/8/2020

4

7

� Be present (physically)

� Be present (mentally)

� Understand the concepts

� Get involved (ask questions, etc)

� Do the assignments

8

�Yes if you � Are interested in process simulation� Are interested in working with equations� Are interested in ‘learning by doing’

�No if you� Hate process dynamics!� Hate math!� Hate computer-aided simulation!� Do not know any coding.� Are too busy to attend the class regularly!

11/8/2020

5

� Citation: � Acknowledge the source (even if your own work).

� Never copy a sentence unless you use quotation and give proper citation.

� Cite credible sources (No Wikipedia please!)

� Collaboration: � Group thinking is encouraged, but codes and write-ups must be

done independently.

� Do not procrastinate; be ahead of time!

� Projects/assignments� Always report results truthfully.

� If you don’t get results, do not push. Step back and check your assumptions, etc.

Copyright © Ali M. Sahlodin, Dept. of Chemical Engineering, AmirKabir Univ. of Tech. 9

10

� Report: Single PDF file� Handwritten OK (take a quality picture and paste into Word)

� Make sure text is legible (use enough light, no shadows)

� Upload to LMS� Email only when LMS is closed (subject line: student #)

� Code must be submitted as a separate file (zip, no RAR)

� All plots, formulas must appear in the report, as requested.� Zero mark if I have to run your code to generate the plots

� Zero mark if I have to see your code to find an equation, etc.

� Please adhere to academic integrity practices (no copying!)

11/8/2020

6


Welcome to the course!

� Merriam-Webster: a system of postulates, data,

and inferences presented as a mathematical description

of an entity or state of affairs.


"All models are wrong but some are useful“ George Box

ProcessInput Output

Simulation•Simply solving the model; no need for a particular software package.

11/8/2020

7

� First-principles models

� Let the physics derive the model (mass/energy balance).

� Data-driven models

� Let the data derive the model.

� Combination models


� No adequate knowledge of

system’s physical behavior

� Perturb the system to identify

it.

� Typical steps

� Collect data set

� Train the model using training

set

� Test the model using validation

set


ProcessInput Output

Model

Calc. output

Machine

learning

Artificial

intelligence

11/8/2020

8

� Operating conditions

� Design alternatives

15

Process design


By mbeychok, Wikipedia CC BY SA 3.0

� How to reach design

specifications?

� How to maintain design

specifications?

� What-if scenarios

16

Process operation



11/8/2020

9

� Replace equipment

� Change products

17

Process modifications



� Maximize

production/profit

� Minimize cost

18

Process optimization



11/8/2020

10

� Micro-scale modeling (control volume)

� Use of simulation software

� Mostly steady state


IN OUT

COCO (HDA process)

� How complex transient (dynamic) processes are

modeled.

� How resulting dynamic models are solved.

� How process simulators work

� How to use and troubleshoot process simulators

effectively

� How to go beyond merely using a simulator.


11/8/2020

11

� Dynamic systems

� are more fun!

� are less discussed.

� are less understood by engineers.

� Have more applications than you

might have thought.

� Complex dynamic systems are (a lot

of times) not handled properly by

commercial simulators


Learning DYNAMICS gives you an edge!

time

� ?

� ?

� ?

� …


11/8/2020

12

� Inherently dynamic

� Pharmaceuticals

� Specialty products


T(t)

t

V(t)

t

CC(t)

t

FA

A+BC

� Product grade transition

� Feedstock changes

� Startup and shutdown


tstartup shutdown

Process

variable

Reactor

Separation

Feed Product

11/8/2020

13

� Examples:

� Minimize startup time

� Minimize startup waste

� Maximize yield in a batch process

� We need a model for optimization


What temperature profile maximizes production?

FA

A+BC

heat

� Process control is all about dynamics!

� Advanced control algorithms require process models

� Model predictive control


Seader’s Chapter 20 Supplement

11/8/2020

14

� Which one should I learn in a graduate course?


COCO (HDA process)

� Steady-state and dynamic modeling

� Refresher on differential equations (ODEs, PDEs)

� Differential-algebraic equations (DAEs)

� Theory of DAEs, solution methods

� Processes with hybrid dynamic models

� Modeling and simulation methods

� Plant-wide simulation

Steady-state/dynamic

� Sequential-modular/Equation-oriented (simultaneous)


11/8/2020

15

29

Numerical Solution of Initial-Value Problems in Differential-Algebraic Equations

K. E. Brenan, S. L.

Campbell, and L. R.

Petzold, 1995

Analysis, Synthesis, and Design of Chemical Processes

Turton, R., Bailie, R.C., Whiting,

W.B., Shaeiwitz, J.A., Debangsu

Bhattacharyya , 4th Edition,

Prentice-Hall International Series

in the Physical and Chemical

Engineering Sciences, 2012.

Research papers/online material


Systematic Methods of Chemical Process Design

Lorenz T.

Biegler, Ignacio E.

Grossmann, Arthur W.

Westerberg

Prentice Hall PTR, 1997

modeling simulation lecture1

Documents