RTD software for identification of spatially localised models and data standardisation R.Žitný, J.Thýn Czech Technical University in Prague.

RTD software for identification of spatially

localised models and data standardisation

R.Žitný, J.Thýn

Czech Technical University in Prague

.History of RTD software development at CTU

• Radiotracers group UVVVR since 1965. • First generation of RTD (mainframe), 1973-1980• Second generation (HP Basic), 1978-1989• Third generation (IBM PC), 1989-1999

• Fourth generation ?

First generation of RTD

R TD 1L ag u erre fu n c tion s

R TD 2Tim e d om ain

R TD 3Id en tifica tion

R TD in te rp re t

• Portability (Fortran 4, file oriented I/O)• Transparency (easy modifications)• Simple (user friendly) definition of batch

Example of batch (identification)

– INPUT(1)

– INPUT(2)

– NORM2(1,2)

– ECOEF2(1,2,3)

– TPOINT(3)

– STOP

– data (ti,ci) for time curve 1 – inlet stream

– data (ti,ci) for time curve 2 – outlet stream.

Third generation of RTD

R TD 0c (T) p rocess in g

n on -eq u id is tan t fu n c tion scorrec tion s

R TD 1Tim e/F ou rie r d om a in

con vo lu tion /d econ vo lu tionsp lin es , L ag u erre , F F T

R TD 2N u m erica l so l. O D E

id en tifica tionin te rac tive m od e ls M D F

R TD

Interactive Fortran77, (Matrix Editor, PF) Regularisation in time, Fouriere, Laguerre domain Identification of mixed type parameters (integer/real) Definition of models using MDF

Flow un it characterised by

(t,E or by Fourier series)C onvo lution and deconvolu tion

IMPULSE RESPONSES

Flow unit characterised by

(first o rder, non linear)N um erica l in teg ra tion

DIFFERENTIAL EQUATIONS

RTD1

RTD2

Black - Gray box analysis

Model definition file (MDF)C______1 series & backmixing [P1] Backmixing ratio [email protected] [P2] Mean residence time [email protected] [P3] Number of units @3F6.0\\INITreal tm,f,aux integer if=p(1) neq=p(3) tm=p(2)/neq c(1)=1/tm\\MODELdc(1)=(x+f*c(2)-(1+f)*c(1))/tmi=1while i<neq-1 do begin i=i+1 aux=(1+f)*c(i-1)+f*c(i+1)-(1+2*f)*c(i) dc(i)=aux/tm enddc(neq)=((1+f)*(c(neq-1)-c(neq)))/tmy=c(neq)\\PARAM

Models defined by users

variable flow/volume, axial dispersion collimation characteristics, heat transfer multiple inlets/outlets, heterogeneous system batch systems

RTD0 application

• Steam velocity. Venturimeter calibration;(NZ)

• Effective volume, holdup. Waste stabilization pond (Ph; Ml), Holding tanks (Alumina

industry) (Au), Rotary kiln (Cz)

• Parallel flows, bypass,channeling. Tank with settler - pilot plant (K), Ethylalcohol

reactor (Cz), Precipitation tanks (Au), Holding tanks (Au)

• Mixing characteristic, axial dispersion

• Recirculation flowrate ratio• Separation effect,tracer balance. Cement industry -Cyclone (K)

M om ents , peaksvarian ce , a rea , P ec le t

C orrec tionsb ackg rou n d ra ise , ta il, d ecay

D ecom pos itionreg ress ion (exp on en tia l, p ow er)

Z -trans form ationvariab le flow

O p era tion s

RTD1 application

C rosscorre la tiont im e d e lay, P R B S , freq u en cy ch ar.

S plines (l in ear/cu b ic) F F T (s in ,cos) L aguerre func tions

(D e)convolution - regula r isa tionE (t) id en tifica tion , resp on se p red ic t ion

S ystem s w ith recyc lesid en tifica tion , resp on se p red ic tion s

O p era tion s

• Flow rate measurement. Steam velocity measur.(NZ), flowrate measurement (K), incinerator

(NZ), temperature disturbances (extremely slow flowrate) (Cz)

• RTD functions: E(t), F(t), (t). Fluidized catalytic cracking (Au, Fi), Settling tank;

waste water treatment (Cz), Heat exchanger (In,K), Evaporator (In), Aniline reactor (In), Indirect rotary dryer (In), Mercury removal unit (Th), Electron beam gas chamber (K), Direct ohmic heating (Cz)

• Smoothing, disturbance attenuation. Waste water treatment (Cz)

• Transfer functions, Frequency characteristics, Waste water treatment

(Cz), furnace for glass (Cz)

RTD2 application

M ultip le in le tsresp on ses , id en tifica tion

Im pulse responsesid en tifica tion

T im e dom ain m ode lsP red ic tion s , id en tifica tion

L aplace trans form ation

L aplace dom ain m ode lsId en tifica tion , resp on se p red ic t ion

• Pilot plants. Mixed Tank (K); Extractor (Tl), Hygienization irradiator for waste water (batch system)

• Waste water treatment. Tank of activated sludge (TAS), air tubes (Ge), aeration turbines (Cz)

Gold system of activation (Cz), Sedimentation tanks (Cz), Equalization unit (Cz) Facultative oxidation Pond (Ph,Ml)

• Heat exchangers. Tubular heat exchanger (In),(K)

• Evaporation, dehydratation. Semi-Kestner (sugar industry) (In), Rotary dryer (In),

Dehydratation rotational furnace (pigment production) (Cz)

• Reactors. Production of aldehydes (Cz), Production of aniline (In), FCC crackinkg (1)Au, (2) Fi),

• Alumina production (Au). Precipitators; digestors; agglomeration, holding tanks

• Electron beams gas chamber (K). Chamber with baffles, chamber without baffles

• Disintegration effect Hammer mill (Cz), drum furnace (Cz)

Process modelling, LPM and CFD

• Lumped Parameter (LPM)• Computer fluid dynamics (CFD)• Combined Models (CM)

0102030405060708090

100

Past Present Future

LPMCFDCMEXP

?tracer

EXPeriments

Why spatially localised models?

• Improved description and design of processes

• Improved diagnostics• Residence time and temperature time T(t)• Thermal or irradiation treatment

Reaction is where?

I(z)

z

H1

H2 u(r)

D

Spatially localised LPM

• Series

• Parallel

Constant concentration in the view field

Distance=?

Distance=?

Non-uniform concentration in the view field

LPM & collimation algorithm

dccore/dxmeasured

10

100

1

1000 dcwall/dxmeasured

excentricity [-]

r/R=0.1

r/R=0.9r/R=0.1

r/R=0.9c C x C x

c C x C xcore

wall

11 1 12 2

21 1 22 2

dc

dxC C

dc

dxC C

core

wall

112

122

212

222

FCC -Fluidised Cracking Core - Anulus model (ccore, cwall =?)

EXP & collimation algorithm

CollimatedDetector

DirectOhmicHeating

CFD & collimation algorithm

CollimatedDetector

DirectOhmicHeating

FEM-COSMOS/M

CV-FLUENT (600000 nodes, 600 MB results)

CFD/EXP collimation algorithm

RdR

d h z

z1 22 2

;

( )

h

de

z

r

ehr

z

S Rb

eRR

b

eRb 1

2

122

2

arcsin arcsin

dJSz

r zc t r r z dz dr rd

4 2 2 3 2

( )( , cos , sin , )/

b R R e R R 1

24 1

222 2

12

22 2( )

Focused collimation algorithm

Focusedcollimateddetector

4th generation RTD software

• Project file

• Script

• Programs

Optimisedparameters

$MDFname\\icon {bitmap file reference)<! comment keywordsINTEGER, REAL,IF THENWHILE DOBEGIN END operators+ - * / ** = <= >= <> | & () functionssin,cos,exp,log,abs,min,max,erf,gama,rnd,atn,bj,by (Bessel funct.,Laguerre, Legendre, Cheb. polyn.)COLC(), COLS() - collimators system variablesT,X,Y,C(),DC(),P(),NEQ,NP,..>\\INITIAL....initial conditions

\\MODEL... diff. equations defining model

$PARnamename MDF<! model parameters>p1,...

$CTname<!time course (dt=time step)>\\dtc1

....cN

$CFnamename CT<! Fourier transform>\\dfRe1 Im1

...

ReN, ImN

$JOURNALname<! >

$MDF-FTPname<! model definition >URL

$COLLIMname<! comment>geometry,window,...

$CONNECTnamename XYZ<!connectivity matrix forCFD results>el1 M1 i1 ...iM1

...

$XYZname<! nodal points coordinates(CFD results)>coordinate system1 x1 y1 z1

...

$CTNnamename XYZ<! Predicted nodal valuesat a specified time>time1 c1

2 c2

...

$TUPLEXINname<! example of "foreign"CFD program>

Data manager(filters)

Model solver(MDF)numericalintegration

Model solver(fixed models)numericalintegration

FFT

Deconvolution(regularisation)

Rxx Rxy

Convolution

Normalisation

Comparion(optim. criteria)

Collimator/detector

Fluentconversion

Cosmosconversion

SCRIPTsequence ofcalledprograms andspecificationof data, i.e.PROG [namesof sections $..]

Working files

OPTIM

Conventions adopted:- section begins with $ in the

first column- name-arbitrary name of a

specific instance- <! ...> any comments

Conceptualscheme

CORE

• Project file

• Script

• Programs

FRONTEND

• Windows

• Visual studio?

• Linux

GTK libraryfor Windows and Unix

UNIX orWindows ? B.G.makes

stars from secretaries and idiots from experts