Performance Characteristics of 2D Axial Flow Turbines — Lesson 3

This lesson covers the fundamental aspects of turbomachinery aerodynamics, focusing on turbines, particularly axial flow turbines. It delves into the basics of turbines, their thermodynamics, and the different types of turbines, including axial flow, radial flow, and mixed flow turbines. The lesson also discusses the two configurations of axial turbines, impulse turbine and reaction turbine, and how they differ in terms of enthalpy drop. It further explains the concept of degree of reaction and how it can be used to distinguish between these two types of turbines. The lesson also touches on the losses encountered in a turbine, the different forms of efficiency, and the impact of loading on efficiency.

Video Highlights

02:52 - Discussion on the losses encountered in a turbine and the different forms of efficiency in a turbine.
19:05 - Explanation of the concept of Total-to-static efficiency and Total-to-total efficiency in turbines, and their relevance in different applications.
33:36 - Explanation of the different types of losses in a turbine, including viscous losses, 3-D losses, shock losses, and mixing losses.
45:30 - Discussion on the concept of deviation in the context of nozzle flow in turbines.

Key Takeaways

- Turbines can be classified into three types: axial flow, radial flow, and mixed flow turbines.
- Axial turbines can be further classified into two configurations: impulse turbine and reaction turbine.
- The degree of reaction is a parameter that can be used to distinguish between impulse and reaction turbines.
- Turbines encounter various forms of losses, including viscous losses, 3-D losses, shock losses, and mixing losses.
- The efficiency of a turbine can be measured in different ways, including Total-to-static efficiency and Total-to-total efficiency.
- The efficiency and performance of a turbine can be influenced by the degree of reaction and loading.