Question: In a recuperative air preheater, the heat is transferred____________________?

• 1. from a metal wall from one medium to another
• 2. from heating an itermediate material and then heating the air from this material
• 3. by direct mixing ,
• 4. heat is transferred by bleeding some gases from furnace

Question: In which of the following boilers, the draught in furnace is increased by utilising exhaust steam from engine__________________?

• 1. lancashire boiler
• 2. locomotive boiler
• 3. babcock and wilcox boiler
• 4. cochran boiler

Question: The heat loss in a boiler takes place in the form of________________?

• 1. heat carried away by flue gases
• 2. heat carried away by ash
• 3. moisture present in fuel and steam formed by combustion of hydrogen in fuel
• 4. all of the above

Question: In forced circulation type boiler__________________?

• 1. heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum
• 2. water is supplied in drum and through down-comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam
• 3. feed pump is employed to supplement natural circulation in water wall type furnace
• 4. water is converted into steam in one pass without any recirculation

Question: The overall efficiency of thermal power plant is________________?

• 1. boiler efficiency, turhine efficiecny, generator efficiency
• 2. all the three above plus gas cycle efficiency
• 3. carnot cycle efficiency
• 4. regenerative cycle efficiency

Question: The radius of a dished head is taken approximately as______________________?

• 1. one-fourth
• 2. half
• 3. one
• 4. two

Question: Thermal efficiency of a thermal power plant is of the order of___________________?

• 1. 15%
• 2. 20%
• 3. 30%
• 4. 45%

Question: Pick up wrong statement about desired properties of a good fuel__________________?

• 1. high calorific value
• 2. produce minimum smoke and gases
• 3. ease in storing
• 4. high ignition point

Question: Which is not correct statement about pulverised fuel firing ?

• 1. high burning rate is possible
• 2. heat release can be easily controlled
• 3. fuel burns economically
• 4. it is the best technique for burning high ash content fuel having low fusion ash

Question: Which is not correct statement about the function of furnace____________________?

• 1. to provide proper conditions for con-tinuous complete combustion
• 2. mix fuel with air and ignite
• 3. separate ash from coal
• 4. maintain heat supply to prepare and ignite the incoming fuel