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Top 20 Steam Turbine Basics Questions You Need to Know

Top 20 Steam Turbine Basics Questions You Need to Know

Introduction
A steam turbine converts high-pressure, high-temperature steam into shaft work — the core principle behind power generation in many thermal power plants. In this post, we bring you 20 essential questions and answers that cover the basic theory, components, and classification of steam turbines. Whether you’re preparing for exams or interviews, these Q&As will help you refresh the fundamentals quickly.

Table of Contents

  1. What does a steam turbine convert?

  2. How many steps are involved in its energy conversion process?

  3. What are the types of turbines based on back pressure?

  4. What does “compound arrangement” of a turbine refer to?

  5. What are the basic components of a steam turbine?

  6. What does thermal equilibrium in steam flow mean?

  7. Define “reheat factor.”

  8. What does a regenerative steam cycle render?

  9. What is a nozzle?

  10. What is a diffuser?

  11. How is flow through a nozzle regarded?

  12. What is “critical pressure” in context of steam flow?

  13. What kind of action does steam impose in a turbine?

  14. What is “internal efficiency”?

  15. What is “blading efficiency”?

  16. What is a convergent nozzle?

  17. What are the types of multi-stage steam turbines?

  18. What drives an impulse-reaction turbine?

  19. Where is frictional loss assumed in a nozzle?

  20. What is the degree of reaction when certain enthalpy drop conditions apply?

Q&A – Steam Turbine Basics

Q1. A steam turbine converts the output from a steam generator into what?
Ans. A steam turbine converts the energy of high-pressure, high-temperature steam supplied by a steam generator into shaft work.

Q2. The energy conversion occurring in a steam turbine is a ______ step process?
Ans. The process is two-step: steam first expands in a nozzle, gaining velocity; then it loses this velocity when it impinges on the blades.

Q3. Depending on whether the back pressure is below or equal to atmospheric pressure, how many types of turbines exist?
Ans. There are two types: condensing and non-condensing turbines.

Q4. The overall steam turbine generator arrangement of a power plant is designated as ______ compound on the basis of shaft orientation.
Ans. The arrangement is designated as tandem or cross-compound based on shaft orientation.

Q5. A steam turbine is basically an assemblage of what?
Ans. Nozzle and blades.

Q6. Thermal equilibrium means that the flow of steam is what kind of flow?
Ans. When the steam flow is isentropic, it is at thermal equilibrium.

Q7. The reheat factor is the ratio of what?
Ans. The ratio of cumulative heat drop to the isentropic heat drop is called the reheat factor.

Q8. What does a regenerative steam cycle render?
Ans. It renders decreased work output per unit mass of steam as well as increased thermal efficiency.

Q9. What is a nozzle?
Ans. A nozzle is a duct through which the velocity of a fluid increases at the expense of pressure.

Q10. A duct which decreases the velocity of fluid and causes a corresponding increase in pressure is called what?
Ans. Diffuser.

Q11. How is the flow through a nozzle regarded?
Ans. The flow through a nozzle is regarded as isentropic flow.

Q12. What does the critical pressure give in the context of a nozzle?
Ans. The critical pressure gives the velocity of steam at the throat, which is equal to the velocity of sound.

Q13. What is the action of steam in a steam turbine?
Ans. Steam action in a steam turbine is dynamic.

Q14. The ratio of total useful heat drop to the total isentropic heat drop is called what?
Ans. Internal efficiency.

Q15. The ratio of the work done on the blades to the energy supplied to the blades is called what?
Ans. Blading efficiency.

Q16. When is a nozzle said to be a convergent nozzle?
Ans. When the cross-section of the nozzle decreases continuously from entrance to exit.

Q17. Multi-stage steam turbines are of which types?
Ans. The types are reaction, velocity-compounded, and pressure-compounded turbines.

Q18. What drives an impulse-reaction turbine?
Ans. The driving force is partly impulsive and partly reactive; the components add up to the resultant force.

Q19. In a nozzle, where is the frictional loss assumed to occur?
Ans. The entire frictional loss is assumed to occur between the throat and the exit of the nozzle.

Q20. If the isentropic enthalpy drop in the moving blade is two-third of that in fixed blades, what is the degree of reaction?
Ans. The required degree of reaction will be 0.67.

Why This Q&A Matters

  • This set of 20 questions covers the basics of steam-turbine theory, components, and classification — often asked in boiler/turbine-related exams and interviews.

  • It’s ideal for revision, quick reference, or preparation for technical interviews and exams related to power-plant operations (like BOE, turbine operator, etc.).

  • Clear, direct questions & answers make the content skim-friendly and easy to use for students and professionals alike.

Suggestions — Next Steps for Readers

  • Bookmark or print this post for easy offline review.

  • Share with peers preparing for interviews or exams.

  • Check out related posts on this blog for boilers, condensers, DM plants, pumps, etc. to build holistic knowledge of the power-plant domain.

Conclusion
Understanding the fundamentals of steam turbines is essential for anyone working in thermal power plants or preparing for related exams. This Q&A post helps you quickly revise the essential concepts. If you have further doubts, you can comment below — I’ll try to clarify.


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