Hydraulic turbomachines

This course covers the design of hydraulic turbomachines and their subsequent system integration. Basic principles of energy transfer are explained, followed by preliminary design procedures, prediction of performance characteristics, and issues related to application and selection.

The types of turbomachines dealt with in this course include centrifugal pumps and fans (radial flow, mixed-flow, axial flow), hydro turbines (Pelton, Francis, Kaplan, Bulb), and open-type machines such as tidal turbines, wind turbines, and marine propulsors (axial flow propellers, ducted propellers, Darrieus type cross flow).

Several topics will be addressed that are universal to hydraulic turbomachinery, such as cavitation (NPSH, suction specific speed), efficiency (net power, shaft power, specific energy, losses), and scaling of performance (similarity theory, Reynolds effects)

The design of turbomachines also requires dealing with phenomena specific to a particular class of machines. Examples include:

• For hydraulic turbines: the design of draft tubes, prevention of vortex ropes, S-type instabilities, runaway conditions at load rejection, water hammer and surge chambers, pumped storage hydroelectricity, reverse operation and 4-quadrant operation.
• For centrifugal pumps: air entrainment, unstable performance, variable speed control.
• For wind and tidal turbines: blade element and momentum method, induced velocity, wake rotation, Betz efficiency limit, power and speed control.
• For axial and radial flow turbomachines: blade layout analysis, blade loading, degree of reaction, and diffusion limits

The student is familiar with the various types of hydraulic turbomachines and their application. He/she understands the underlying physical principles in fluid mechanics. The student knows the practical and physical limits for application and is able to make suitable assumptions and simplifications required for selection, system integration, and operation. He/she can design various types of hydraulic turbomachines for a variety of applications and is able to incorporate criteria such as cost and energy consumption.