Entropy Generation in Thermodynamics — Lesson - 3

This lesson covers the concept of entropy generation in thermodynamics, focusing on its application in various devices like mixing chambers, heat exchangers, and turbines. It explains how to calculate the rate of entropy generation using steady flow energy equations and entropy balance equations. The lesson also discusses the impact of internal and external irreversibilities on entropy generation. For instance, it explains how heat transfer across a finite temperature difference can cause entropy generation due to internal irreversibility. The lesson provides several examples to illustrate these concepts, such as a steam turbine losing heat to its surroundings and a refrigerant being compressed in a compressor.

Video Highlights

02:29 - Concept of throttling and its application in a domestic refrigerator
05:55 - Rate of entropy generation inside the heat exchanger
09:44 - Power developed and rate of entropy generation in a steam turbine
14:40 - Concept of refrigerant compression and its application in a compressor
20:47 - Concept of a steam turbine and its application in a turbine

Key Takeaways

- Entropy generation is a crucial concept in thermodynamics, which occurs due to internal and external irreversibility.
- The steady flow energy equation is a vital tool for calculating the rate of entropy generation in various devices.
- In a heat exchanger, entropy generation occurs due to heat transfer across a finite temperature difference.
- In a steam turbine, entropy generation happens due to friction, both mechanical and fluid friction.
- The rate of entropy generation in the universe is a significant performance metric for any device or process.