Slide 1
Fluid energy turns a turbine shaft
A turbine converts part of a fluid’s available energy into shaft work. Flow through its blades creates a turning force.
More to Read
The fluid may be water, steam or hot gas. Each has different density, temperature and compressibility, so turbines serving them need different geometry and materials.
Slide 2
Changing the flow’s momentum provides torque
Blade passages turn and accelerate or decelerate the flow. The resulting momentum change provides torque to the rotor.
More to Read
Stationary guide vanes can prepare the direction entering a rotor. Several stages can divide a large pressure or energy change into manageable steps instead of demanding it all from one blade row.
Slide 3
Water power depends on both flow and head
A water turbine’s available power depends on flow and hydraulic head: the relevant energy per unit weight of water.
More flow alone does not describe the energy available at a site.
More to Read
Head represents the relevant energy per unit weight of water. Pipe losses reduce the head reaching the turbine, linking civil layout and hydraulic design with the machine’s output.
Slide 4
A gas turbine must drive its own compressor too
In a gas turbine, part of turbine output drives the compressor. Only the remainder is available for external work after other losses.
More to Read
Exhaust can still carry substantial thermal energy. A combined-cycle plant uses some of it to raise steam for another turbine, extracting more useful output from the overall process.
Slide 5
Efficiency depends on the operating conditions
A turbine has a useful range of flow, speed and pressure conditions. Performance may decline away from its intended operating region.
More to Read
Control systems adjust flow or other variables to match demand while respecting mechanical limits. Blade stress, vibration and material temperature can restrict output before the theoretical fluid energy is fully used.
Sources
- How Hydropower Works
US Department of Energy
- How Gas Turbine Power Plants Work
US Department of Energy