1 / 14

Characteristic values

Characteristic values. Reaction ratio R Head coefficient y Flow coefficient j. Reaction ratio for hydraulic machines. The reaction ratio can be defined as the pressure fraction of the total net specific energy which is converted to mechanical energy in the runner.

mdunagan
Télécharger la présentation

Characteristic values

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Characteristic values • Reaction ratio R • Head coefficient y • Flow coefficient j

  2. Reaction ratio for hydraulic machines The reaction ratio can be defined as the pressure fraction of the total net specific energy which is converted to mechanical energy in the runner.

  3. Reaction ratio for a Pelton turbine Example for a Pelton turbine : cu1 = 1,0 cu2 = 0 u1 = 0,5 cm1 = cm2 R = 0,0

  4. Reaction ratio for a Francis turbine Example for a Francis turbine: cu1 = 0,72 cu2 = 0 u1 = 0,69 R = 0,52

  5. Inlet Runner Outlet guide vanes Inlet guide vanes Outlet Draft tube Outlet runner Energy converted in the turbine Reference line

  6. Reaction ratio for a Kaplan turbine Example for a Kaplan turbine: cu1 = 0,6 cu2 = 0 u1 = 0,83 R = 0,64

  7. u1 w1 c1 w1 u1 c1 c2 w2 Aksialturbin R=0 w u2

  8. w1 u1 c1 u2 c2 w2 Aksialturbin R=0,5 w

  9. Reaction ratio The reaction ratio can be defined as the ratio between the enthalpy difference over the runner and the total change of enthalpy. p3 p3 h h p2 p2 3 0 Guidevanes Guidevanes p1 p1 1 Runner Runner 2 2 1 s s

  10. Head coefficient for hydraulic machines

  11. Flow coefficient for hydraulic machines

  12. Source: Strømningsmaskiner, Bind 3, Jan M. Øverli

More Related