The design process begins with the construction of velocity triangles.
For , the blade speed remains essentially constant from the inlet to the outlet of a given streamtube ( ) because the radius does not change (
V⃗=W⃗+U⃗modified cap V with right arrow above equals modified cap W with right arrow above plus modified cap U with right arrow above The Euler Turbomachinery Equation axial and radial turbines by hany moustaphapdf 2021
In a radial turbine, the inlet airflow is , meaning the fluid enters the turbine perpendicularly to the axis of rotation and then turns to exit in an axial direction. This "Eiffel Tower" cross-section design, with a substantial hub and thinner blades, contributes to the radial turbine's robustness and ability to handle higher thermal loads without cooling.
) : The pressure drop is evenly split between the stator and rotor, meaning the fluid accelerates as it expands through the rotor blades, enhancing efficiency but increasing axial loads. 3. Comparative Technical Overview The design process begins with the construction of
Radial turbines, also known as radial-inflow turbines or centripetal turbines, operate on a different mechanical principle. The gas enters the turbine wheel at the periphery, flows inward toward the center, and exits along the axis (or vice versa for outflow). This "swirling" motion changes the angular momentum drastically, spinning the shaft.
This equation highlights a fundamental design difference: In axial turbines, $U$ is constant across the stage (ignoring radial variations), simplifying the energy transfer analysis. In radial turbines, the change in radius from inlet to outlet provides a significant contribution to the work output via the $U_1 C_\theta 1$ term, allowing for high pressure drops across a single stage. ) : The pressure drop is evenly split
This essay has provided a detailed review of axial and radial turbines, their design, operation, and applications, based on Hany Moustapha's 2021 PDF publication. The comparison of axial and radial turbines highlights their differences and similarities, and the conclusion summarizes the key takeaways from the review. The references and appendices provide additional information and design parameters for axial and radial turbines.
In 2021, the demand for higher thermal efficiency, driven by climate change mandates and fuel cost volatility, has necessitated a re-evaluation of conventional design limits. While axial turbines dominate the high-power sector due to their ability to handle large volumetric flows with high efficiency, radial turbines maintain a monopoly in small-scale applications where compactness and robustness against particle ingestion are paramount. This paper delineates the theoretical framework required to design and analyze these machines, providing engineers with the necessary tools to navigate the trade-offs between complexity, cost, and performance.
A core element in axial design is the . This historical correlation charts the relationship between: Flow Coefficient (
Unlike their axial counterparts, radial turbines feature fluid that enters perpendicularly (radially) to the shaft axis and is turned 90∘90 raised to the composed with power