THEORY EXAMINATION (SEM–VIII) 2016-17 POWER PLANT ENGINEERING

Power Plant Engineering – Section Wise Explanation

Section A – Basic Concepts of Power Plants

Section A contains short questions that test the basic concepts of power generation systems and power plant components. Students must attempt all questions in this section. 

Power plant engineering deals with the design, operation, and maintenance of systems used to generate electricity. Different types of power plants such as thermal power plants, hydroelectric plants, nuclear power plants, and renewable energy plants are used to produce electrical power.

One important concept in power plant engineering is boiler efficiency, which measures how effectively a boiler converts fuel energy into steam energy. A higher boiler efficiency means better fuel utilization and lower energy losses.

Energy sources are another important concept. Major sources of energy include coal, oil, natural gas, nuclear energy, hydroelectric power, solar energy, wind energy, and biomass energy.

An economiser is a device used in boilers to improve efficiency by preheating feed water using waste heat from flue gases.

Power plant engineers also study factors such as load factor and demand factor, which help determine how effectively electrical power is used by consumers.

Other concepts include volumetric efficiency, which measures the efficiency of air intake in engines, and biogas, which is a renewable fuel produced from organic waste through anaerobic digestion.

In nuclear power plants, a moderator is used to slow down neutrons during nuclear reactions to sustain the chain reaction.

Understanding these basic concepts helps students learn how power plants operate efficiently and safely.

Questions for Section A

What is boiler efficiency?

What are the major sources of energy?

What is the function of an economiser in a boiler?

What is load factor?

What is demand factor?

What is volumetric efficiency?

What is biogas?

What is the function of baffles?

What is a moderator in nuclear reactors?

What is the difference between boiler mountings and boiler accessories?

Section B – Power Plant Systems and Operations

Section B focuses on detailed explanations of power plant components, systems, and environmental effects. Students must attempt any five questions from this section. 

One important topic in this section is the diesel power plant, which generates electricity using diesel engines. A diesel power plant includes several systems such as fuel supply systems, cooling systems, lubrication systems, air intake systems, and exhaust systems.

Another important technology used in thermal power plants is the fluidized bed combustion (FBC) system. In this system, fuel particles are suspended in a stream of air, creating a fluid-like behavior that improves combustion efficiency and reduces emissions.

Lubrication systems are essential for maintaining engine performance and reducing friction between moving parts. Two common types of lubrication systems are wet sump lubrication systems and dry sump lubrication systems.

Nuclear power plants use reactors such as the Pressurized Water Reactor (PWR), where water acts both as a coolant and a moderator to control nuclear reactions.

Environmental issues are also discussed in this section. Acid rain is caused by pollutants such as sulfur dioxide and nitrogen oxides released from power plants. These pollutants react with moisture in the atmosphere and form acidic compounds.

Another important concept is the load curve, which shows how electrical demand changes over time. Load curves help engineers plan power generation to meet demand efficiently.

Power plants also use generators to convert mechanical energy into electrical energy. Proper cooling systems are necessary to prevent overheating in generators.

Questions for Section B

Draw and explain the layout of a diesel power plant.

Explain the working of a fluidized bed combustion system.

Describe the wet sump and dry sump lubrication systems.

Explain the construction and working of a pressurized water reactor.

What is acid rain and how is it controlled?

What is the significance of a load curve and load duration curve?

What is a generator and how is it cooled?

Calculate equivalent evaporation and boiler efficiency for the given boiler data.

Section C – Advanced Power Plant Analysis

Section C contains advanced analytical and design-related questions related to power plant performance and site selection. Students must attempt any two questions from this section. 

One of the important topics discussed in this section is the gas turbine power plant. Gas turbines operate based on the Brayton cycle and are widely used for electricity generation and aircraft propulsion.

In gas turbine systems, parameters such as pressure ratio, turbine efficiency, compressor efficiency, and inlet air conditions determine the power output and thermal efficiency of the system.

Another important topic is hydroelectric power plants, which generate electricity using the energy of flowing water. Selecting the correct site for a hydroelectric plant is crucial for efficient operation.

Factors such as water availability, elevation difference, geological conditions, and environmental impact must be considered when choosing a site.

Hydroelectric plants also include several important components such as dams, reservoirs, turbines, generators, penstocks, and spillways.

The section also discusses advanced boiler technologies such as supercritical boilers and supercharged boilers.

Supercritical boilers operate at pressures above the critical pressure of water, which increases efficiency and reduces fuel consumption.

Supercharged boilers use pressurized air to improve combustion efficiency and increase steam production.

Understanding these advanced technologies helps engineers design efficient and modern power generation systems.

Questions for Section C

Calculate the power output and thermal efficiency of the gas turbine cycle.

What factors should be considered when selecting a site for a hydroelectric power plant?

What are the essential elements of a hydroelectric power plant?

What are supercritical boilers?

What are supercharged boilers?

Conclusion

The Power Plant Engineering exam paper evaluates knowledge at three levels. Section A focuses on basic concepts related to energy sources and power plant components. Section B examines the working and design of different power plant systems. Section C explores advanced topics such as gas turbine analysis, hydroelectric plant design, and advanced boiler technologies. 

Understanding these concepts is essential for engineers working in power generation, energy management, and sustainable energy systems.