|Demonstration Francis Turbine :
Demonstration Francis Turbine
- Francis runner surrounded by 6 guide vanes inside PVC volute with clear acrylic front panel for visualisation
- Guide vanes adjustable when turbine is running with scale to indicate degree of opening and clamp to prevent movement
- Francis runner 60 mm diameter with 12 blades
- Brake force determined using Prony type brake dynamometer
- Inlet pressure gauge with range 0 to 2 bar
- Educational software as an option
A tapering, spiral shaped volute conveys
water to the runner via a ring of guide vanes that are adjustable in
angle to vary the flow through the turbine. Water enters the runner
tangentially at the periphery, flows radially inwards through the blades
towards the hub then exits axially via a draft tube.
Power generated by the turbine is
absorbed by a Prony friction brake consisting of a pair of spring
balances attached to a brake belt that is wrapped around a pulley wheel
driven by the runner. The load on the turbine is varied by tensioning
both spring balances which increases the friction on the pulley wheel.
Brake force is determined from the difference in the readings on the two
spring balances and the torque calculated from the product of this
force and the pulley radius.
The head of water entering the turbine
is indicated on a Bourdon gauge and the speed of rotation is measured
using a non-contacting tachometer (not supplied).
||0 to 1000 RPM
|Diameter of Francis runner:
|Number of blades on runner:
|Number of guide vanes:
||6, adjustable from fully open to fully closed
|Range of spring balances:
||0 to 10 N x 0.1 N
|Range of Bourdon gauge:
||0 to 2 bar