The high flow requires a large passage area, and the low head can be achieved with an axial impeller configuration. This same effect can be seen for a range of Francis turbine runners in Figure 4.

Turbomachinery: Description: Aerodynamic analysis and design of axial flow and radial flow gas compressors and gas turbines. Blade element performance (deflection, profile and shock losses, etc.).

Unified treatment of principles underlying fluid mechanic design of hydraulic pumps, turbines and gas compressors. Similarity and scaling laws. Cavitation. Analysis of radial and axial flow machines.