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Powerhouse layout with vertical axis Francis turbine

Short answer

A vertical-axis Francis powerhouse has penstock and main inlet valve feeding the embedded spiral casing, guide vanes, runner, and draft tube below tailwater. The generator sits above on the same shaft, with thrust bearing, governor, overhead crane, and control room; substructure and superstructure complete the section.

Draw a section/general layout of a powerhouse using a vertical axis Francis turbine, showing the different parts of the powerhouse structure.

Section through a powerhouse with a vertical-axis Francis turbine

      roof
   ============================
   ::::  Overhead crane  ::::     <- crane rail
   |                          |
   |        GENERATOR         |   generator floor
   |__________  |  __________|   (G.F.)
   |  exciter / thrust bearing|
   |     Turbine floor        |   (T.F.)
 --+---   shaft  |   --- Governor
   |      Guide vanes         |
   |  Spiral    ( Runner )    |
   |  casing                  |
   |           \  /           |
   |  Draft tube \/           |   draft tube
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Tailwater
 foundation raft
 Penstock --> Main inlet valve --> Spiral casing

Parts shown

  1. Penstock and main inlet valve (butterfly or spherical valve) at the entry to the spiral casing.
  2. Spiral (scroll) casing embedded in concrete, supplying water around the guide vanes.
  3. Stay ring and guide vanes controlling the flow, operated by servomotors from the governor.
  4. Runner (Francis) mounted on the vertical shaft.
  5. Draft tube under the runner discharging to the tailrace under tailwater.
  6. Turbine shaft, thrust and guide bearings.
  7. Generator (umbrella or suspended type) on the generator floor, with exciter above or below.
  8. Overhead travelling crane on rails spanning the hall.
  9. Governor, oil pressure unit, cooling water, drainage and dewatering in the galleries below.
  10. Superstructure (roof, walls) and the control room beside the generator floor.

✓ Answer checked by Claude Opus 5.5 (high effort)

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