15 Oct 12
This presentation is the property of its rightful owner.
Sponsored Links
1 / 9

CBE 491 /433 PowerPoint PPT Presentation


  • 94 Views
  • Uploaded on
  • Presentation posted in: General

15 Oct 12 Model of Stirred Tank Heater. CBE 491 /433. Goal: set up models to simulate and see effect of tuning parameters 1 st principles (Chaps 3 – 6); transfer functions (just looked at this a bit) process simulators ( AspenPlus Dynamics; CBE 450/550 class).

Download Presentation

CBE 491 /433

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Cbe 491 433

15 Oct 12

Model of Stirred Tank Heater

CBE 491 /433

  • Goal: set up models to simulate and see effect of tuning parameters

  • 1st principles (Chaps 3 – 6);

  • transfer functions (just looked at this a bit)

  • process simulators (AspenPlus Dynamics; CBE 450/550 class)


Cbe 491 433

Stirred Tank Heater (w/ PI Controller)

+

+

+

-

energy balance on tank w/o control

PI controller equation


Cbe 491 433

Stirred Tank Heater (w/ PI Controller)

Let:


Cbe 491 433

ODE Solver (POLYMATH; MATLAB; MATHCAD; etc)

Polymath code:

step= if (t<1) then (0) else (1)

Ti = 0 + step * 10


Cbe 491 433

ODE Solver: POLYMATH

Polymath code (stirred tank heater):

d(C) / d(t) = -1/tau*C + KT/tau*Ti + K1KT/tau*M

C(0) = 0

d(errsum) / d(t) = R – C

errsum(0) = 0

tau = 5 # min

KT = 0.5 # %TO/degC

K1KT = 0.8 # %TO/%CO

R = 0 # set point stays same

M = Kc*(R-C) + Kc/tauI*errsum

step = if (t<1) then (0) else (1)

Ti = 0 + step * 10 # step change disturbance

Kc = 1.3 # %CO/%TO

tauI = 10 # min

t(0) = 0

t(f) = 100 # min

  • In Class Demo / Exercise:

  • Polymath Demonstration

  • Build model in Polymath (ODE solver)

  • Solve; graph C vs t

  • Explore:

    • Try P-only controller

    • Adjust Kc and tauI to get QAD

    • Try different Kc/tauI sets

    • Can you get underdamped response?

    • What is response to step change in R(t); holding Ti at the SS value?


Cbe 491 433

Model of Stirred Tank Heater

CBE 491 / 433

  • Goal: set up models to simulate and see effect of tuning parameters

  • 1st principles (Chaps 3 – 6);

  • transfer functions (just looked at this a bit)

  • process simulators (AspenPlus Dynamics; CBE 450/550 class)


Cbe 491 433

Stirred Tank Heater (transfer function simulator)

+

+

+

-

Transfer function simulator: Loop Pro Developer (Control Station)

  • In Class Demo / Exercise:

  • Build model in Loop Pro Developer (Custom Process)

  • Turn on PI Controller and set Kc and tauI

  • Explore:

    • Change load (Ti) up by 10 to 60%; observe system response

    • Change back to 50%; observe response

    • Try P-only controller

    • Adjust Kc and tauI to get QAD

    • Try different Kc/tauI settings

    • Can you get underdamped response?

    • What is response to step change in R(t) to 60%?


Cbe 491 433

Model of Stirred Tank Heater

CBE 491 / 433

  • Goal: set up models to simulate and see effect of tuning parameters

  • 1st principles (Chaps 3 – 6);

  • transfer functions (just looked at this a bit)

  • process simulators (AspenPlus Dynamics; CBE 450/550 class)


Cbe 491 433

SAVE your Polymath and Loop Pro Developer Models !!


  • Login