Simplified Modelling of Penstock in Hydro-Power Plants

3,945 views

Published on

Modelling of penstock in hydro power plants. Carried out in MATLAB SIMULINK. Can contact author for further details.

Published in: Technology
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
3,945
On SlideShare
0
From Embeds
0
Number of Embeds
9
Actions
Shares
0
Downloads
124
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

Simplified Modelling of Penstock in Hydro-Power Plants

  1. 1. Simplified Modelling of Penstock in Hydro-Power Plants Abhishek Syal   Control & Instrumentation, BHEL Corp. R&D   February-March, 2011
  2. 2. Diagram
  3. 3. Assumptions <ul><ul><li>  Incompressible fluid </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Penstock treated as a single static element </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Rigid penstock </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Density of fluid constant </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Constant surface area of penstock = surface area of inflow tunnel = surface area of outflow tunnel </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Free outflow downstream (hence, no water hammer effect, Qin = Qout) </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Laminar flow </li></ul></ul>
  4. 4. Main Considerations <ul><ul><li>Potential head </li></ul></ul><ul><li>  </li></ul><ul><ul><li>Kinetic head </li></ul></ul><ul><li>  </li></ul><ul><ul><li>Losses due to drag forces (shear due to laminar flow) </li></ul></ul>
  5. 5. Equations <ul><ul><li>  Steady state : </li></ul></ul><ul><ul><ul><ul><li>  K.E. = P.E.   </li></ul></ul></ul></ul><ul><ul><ul><ul><li>=> v = (2gh)^0.5 </li></ul></ul></ul></ul><ul><li>  </li></ul><ul><ul><li>  Transient state : </li></ul></ul><ul><ul><ul><ul><li>F=-dp/dt </li></ul></ul></ul></ul><ul><ul><ul><ul><li>=> h = hin - (L/gA) dQ/dt </li></ul></ul></ul></ul><ul><li>  </li></ul><ul><ul><li>  Losses in head due to Drag forces </li></ul></ul><ul><ul><ul><ul><li>Losses are directly prop. to Q^2 </li></ul></ul></ul></ul><ul><li>  </li></ul><ul><li>  </li></ul>
  6. 6. Modelling <ul><ul><li>Equations modelled in SIMULINK </li></ul></ul><ul><li>  </li></ul><ul><ul><li>Model parameteric values based on pu system </li></ul></ul><ul><li>  </li></ul><ul><ul><li>Subsystem for Penstock created, which can be used in other models </li></ul></ul>
  7. 7. GUI of the Subsystem
  8. 8. Simulation Analysis & Graphs - Case I
  9. 9. Simulation Analysis & Graphs - Case II
  10. 10. Conclusion & Discussion <ul><ul><li>  Effects of slow & fast acting variable </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Factors influencing H's behavior </li></ul></ul>
  11. 11. Really ? <ul><li>  </li></ul><ul><li>  Consider below: </li></ul><ul><li>  One case discussed above is absurd.  </li></ul><ul><li>                   </li></ul><ul><li>                              </li></ul>
  12. 12. Testing & Validation <ul><ul><li>  Needs to be carried out with actual plant data </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Analysis of modelling applicability </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Development of model to increase its accuracy </li></ul></ul>
  13. 13. Further Development Approach <ul><ul><li>  Include Water hammer effect (Qin        Qout, pipe no longer rigid) </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Have a control valve downstream </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  What are the differential flow rates, and heads at various points along the length of penstock? (Integration Approach) How does this model compare with the simplified model?  </li></ul></ul><ul><li>  </li></ul><ul><ul><li>  Different Surface Areas: Is there any effect of change in Internal Pressure head? Does it make any difference? (Ref. Bernoulli's Principle) </li></ul></ul>
  14. 14. Thank You :-) This work may be freely redistributed/utilized for the purpose of education without any prior permission subject to sole condition of  crediting with the Author's name and contact, wherever and in whichever form this work is used. Abhishek Syal [email_address] www.twitter.com/Abhishek_Syal http://in.linkedin.com/in/abhisheksyal
  15. 15. References <ul><ul><li>wikipedia </li></ul></ul><ul><li>  </li></ul><ul><ul><li>google books </li></ul></ul><ul><li>  </li></ul><ul><ul><li>hydro models developed by Marc, Opal RT </li></ul></ul>

×