ABSTRACT
Radial inflow turbines have a long history and predate axial machines by many years. The first truly effective radial turbines were water turbines. In this chapter, only radial inflow turbines working with compressible fluids are discussed. Radial inflow turbines are not as common as radial flow (centrifugal) compressors. Like the latter most radial inflow turbines are relatively low specific speed machines suitable for applications with low flow rates and large pressure drops. They are also simpler and cheaper than axial turbines and so are used when weight and cost are more important than efficiency. The inward-flow radial (IFR) turbine covers tremendous ranges of power, rates of mass flow, and rotational speeds, from very large Francis turbines used in hydroelectric power generation and developing hundreds of megawatts down to tiny closed cycle gas turbines employed in space power generation of a few kilowatts [1].
