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Interactive Self-Study Module: Turbines and Compressors

Overview:

This module uses screencasts and an interactive simulation to explain how to apply the first law for a steady-state flow system to calculate work for a reversible turbine or compressor. It also explains how to apply the first law to a turbine or compressor whose efficiency is less than 100%. It then provides example problems to allow the user to test themselves. Your retention of material in this module will increase if you write down reasons for your answers to ConcepTests, questions in screencasts, and questions to answer before using interactive simulation, and you try to solve the example problems before watching the screencast solutions. We suggest using the learning resources in the following order:

  1. Attempt to answer the multiple-choice ConcepTest and solve the example problem before watching the screencasts or working with the simulations.
  2. Watch the screencasts that describe how to perform energy balances to solve turbine problems and adiabatic compression/expansion processes and answer the questions within the screencasts.
  3. Review important equations for turbines and compressors.
  4. Use the interactive simulation to further understand the behavior of compressors or turbines with different efficiencies.
  5. Try to solve the example problems before watching the solutions in the screencasts.
  6. Answer the ConcepTests.
  7. Look at the list of key points, but only after you try to list the key points yourself. 
Motivation:
  • Turbines are used to generate work from a high-pressure gas or from a high-pressure steam feed. Compressors are to increase the pressure of gases. 
  • This module is intended for a thermodynamics course.
Before studying this module, you should be able:
After studying this module, you should be able to:
  • Distinguish between thermal efficiency and efficiencies of a compressor, or turbine that is due to irreversibilities.
  • Apply efficiencies to calculate work for irreversible compressors and turbines.
  • Calculate outlet temperatures for compressors and turbines