Description : In multi stage compressor, the isothermal compression is achieved by A. Employing intercooler B. By constantly cooling the cylinder C. By running compressor at very slow speed D. By insulating the cylinder
Last Answer : ANSWER : C
Description : The current zero interruption, in oil and air blast circuit breakers, is achieved by (a) lengthening of the gap (b) cooling and blast effect (c) both (a) and (b) (d) deionizing the oil with forced air (e) none of the above
Last Answer : (c) both (a) and (b)
Description : In a diesel engine the high temperature needed to ignite the fuel is achieved by – (1) using heat from exhaust (2) the battery (3) compressing air in the cylinders (4) an electrical spark
Last Answer : (3) compressing air in the cylinders Explanation: Diesel engines use the heat of compressed air to ignite the fuel (intakes air, compresses it, then injects fuel). Diesel engines need high compression ratios to generate the high temperatures required for fuel auto ignition.
Description : Fuel economy in an industrial furnace operation cannot be achieved by the use of (A) Stoichiometric combustion air (B) Non-preheated combustion air (C) Combustion air not enriched with oxygen (D) Recuperators
Last Answer : (A) Stoichiometric combustion air
Description : In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid ... of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace
Last Answer : (C) Imperfect mixing of fuel & air and infiltration of air
Description : Fuel economy in furnaces can be achieved by (A) Using oxygen enriched combustion air (B) Preheating the combustion air (C) Reducing the heat loss through furnace openings & doors (D) All (A), (B) and (C
Last Answer : (D) All (A), (B) and (C
Description : Higher furnace temperature cannot be achieved by use of a lean fuel gas in the furnace by (A) Increasing the draft in the furnace (B) Preheating the fuel gas (C) Oxygen enrichment of combustion air (D) Preheating the combustion air
Last Answer : (A) Increasing the draft in the furnace
Description : Higher efficiency in the combustion of solid fuel cannot be achieved by (A) Proper fuel preparation (B) Keeping the flue gas exhaust temperature very high (C) Adopting efficient-fuel firing technique & equipment (D) Supplying correct quantity of combustion air
Last Answer : (B) Keeping the flue gas exhaust temperature very high
Description : Higher fuel combustion efficiency cannot be achieved by (A) Preheating of fuel gases & combustion air (B) Reducing sulphur content in the fuel (C) Adopting proper fuel firing technique & fuel preparation (D) Supplying correct amount of combustion air
Last Answer : (B) Reducing sulphur content in the fuel
Description : Which of the following is not increased by using preheated combustion air in place of ordinary air at room temperature? (A) Calorific value of the fuel (B) Flame temperature achieved (C) Speed of combustion of fuel (D) Heat transfer rate to the stock in the furnace
Last Answer : (A) Calorific value of the fuel
Description : Maximum endurance: a. Can be achieved in level unaccelerated flight with minimum fuel consumption b. Can be achieved by flying at the best rate of climb speed in straight and level flight c. Can be achieved in a steady climb d. Can be achieved by flying at the absolute ceiling
Last Answer : a. Can be achieved in level unaccelerated flight with minimum fuel consumption
Description : In a diesel engine the high temperature needed to ignite the fuel is achieved by (1) using heat from exhaust (2) the battery (3) compressing air in the cylinders (4) an electrical spark
Last Answer : compressing air in the cylinders
Description : How system grounding and equipment grounding achieved?
Last Answer : System grounding is obtained by grounding the neutral through resistance, through transformer and through effective or solidly grounding. Equipment grounding is obtained by Grounding of non-current carrying metallic parts ... cables. d. Body of portable equipment such as iron, oven, etc.
Description : How dissolved oxygen control is achieved in feed water system?
Last Answer : Hydrazine is added to feed water system to control dissolved oxygen.
Description : How turbine oil purification is achieved?
Last Answer : Oil purification is achieved by centrifugal operation.
Description : Why condenser back-pressure must be low? How it is achieved?
Last Answer : Condenser back- pressure must be low, because steam should be dumped into the condenser so as to recycle it to boiler through the recycle process. It improves efficiency of the turbine, as the heat ... water in the condenser through the tubes of the condenser so that maximum vacuum can be obtained.
Description : How speed control of DC motor can be achieved?
Last Answer : Induced emf in the armature E = P * φ * Z * N / A * 60 volts. Where Z and A are constant. N ∝ Eb / φ N ∝ V - Ia ra / φ. We can consider that the Ia ra drop is ... be varied by varying either applied voltage to the armature and by varying field flux or field strength per pole or total field flux.
Description : What is the cooling water used in moderator heat exchanger during normal operation? And during class IV failure?
Last Answer : During normal operation process LP water is used in moderator heat exchangers, which transfers heat to seawater. During class IV failure firewater is used for the moderator heat exchanger.
Description : The CO2 fixation during C4 pathway occurs in the chloroplast of (a) guard cells (b) bundle sheath cells (c) mesophyll cells (d) spongy parenchyma.
Last Answer : (c) mesophyll cells
Description : In the leaves of C4 plants, malic acid formation during CO2 fixation occurs in the cells of (a) bundle sheath (b) phloem (c) epidermis (d) mesophyll.
Last Answer : (d) mesophyll.
Description : In leaves of C4 plants, malic acid synthesis during CO2 fixation occurs in (a) bundle sheath (b) guard cells (c) epidermal cells (d) mesophyll cells
Last Answer : (d) mesophyll cells.
Description : Mark correct option a) Bill of franking machine used is prepared in form MS10 b) In RMS offices, letter box key should be kept in custody of Sorting Assistant c) Greeting cards are treated as first class ... Label bundle should not contain more than 50 to 60 letters & post cards. e) All of the above
Last Answer : ) All of the above
Description : Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure
Last Answer : ANSWER a. supplying the engine with air at a density greater than the density of the surrounding atmosphere
Description : A __________ is a type of heat exchange system where water is heated to its' boiling point via combustion of a fuel blown through a tube submerged in water. a. Condensate loop b. Hyperbolic cooling tower c. Steam boiler d. All of above
Last Answer : c. Steam boiler
Description : The electric motor in hybrid car can also act as_____ • A generator • A Fuel pump • Cooling fan • Compressor
Last Answer : • A generator
Description : The EGT indication on a piston engine is used: a. To control the cooling air shutters b. To monitor the oil temperature c. To assist the pilot to adjust the fuel mixture d. To indicate cylinder head temperature
Last Answer : c. To assist the pilot to adjust the fuel mixture
Description : In accordance with Coast Guard Regulations (46 CFR), a circuit breaker located in the machinery space and installed in a 440V AC system must _____________. A. be dependent upon mechanical ... the maximum asymmetrical shortcircuit current available at the point of application D. all of the above
Last Answer : Answer: C
Description : If overloading a DC machine becomes necessary in an emergency, you should ____________. A. cool the machine with portable blowers and fans B. hold thermal overload relays open with blocks of ... the windings for cooling D. increase the residual magnetism value of windings to reduce eddy currents
Last Answer : Answer: A
Description : Two contributors of electronic console failures are heat and vibration. To combat some of their effects, preventive maintenance procedures should include ______________. A. systematic rotation of circuit cards with those ... bolts and changing of the air in the control room D. all of the above
Last Answer : Answer: B
Description : What type of cooling is provided for Generator in power plant?
Last Answer : Hydrogen gas cooling is employed for large size generators because of better heat carrying ability of the hydrogen. Hydrogen cooling is provided for rotors and core of the generator. Water cooling is provided for the stator of the alternator.
Description : Why cooling towers require in the Steam power plant ?
Last Answer : Cooling towers cool the warm water discharged from the condenser and feed the cooled water back to the condenser. There are two types of cooling methods provided in the cooling towers, they can be either ... finned tubes over which cooling air is passed. Heat is rejected to air as water is cooled
Description : What are the types of cooling systems it transformers?
Last Answer : A. 1. ONAN (oil natural, air natural) 2. ONAF (oil natural, air forced) 3. OFAF (oil forced, air forced) 4. ODWF (oil direct, water forced) 5. OFAN (oil forced, air forced)
Description : Discuss how the ventilation and cooling of large high speed alternator is carried out.
Last Answer : For high speed alternator two cooling methods are available and they are conventional cooling and direct cooling. In conventional cooling methods, radial and axial ventilating ducts are provided in the ... oil or hydrogen are circulated in the ducts to remove the heat directly from the conductors.
Description : How the heat dissipation is improved by providing the cooling tubes?
Last Answer : The cooling tubes will improve the circulation of oil. The circulation of oil is due to effective pressure heads produced by columns of oil in tubes. The improvement in cooling is accounted by taking the specific heat dissipation due to convection as 35% more than that without tubes.
Description : Why cooling tubes are provided?
Last Answer : Cooling tubes are provided to increase the heat dissipating area of the tank.
Description : What are the factors to be considered for choosing the method of cooling?
Last Answer : The choice of cooling method depends on KVA rating of transformer, size, application and the site conditions where it will be installed.
Description : List some methods of cooling of transformers.
Last Answer : A:Air natural, Air blast, Oil Natural, Oil natural air forced, Oil natural water forced, Oil forced, Oil forced air natural, Oil forced air natural, Oil forced water forced.
Description : Why transformer oil is used as a cooling medium?
Last Answer : When transformer oil is used as a coolant the heat dissipation by convection is 10 times more than the convection due to air. Hence transformer oil is used as a cooling medium.
Description : What is the working principle of Cooling Towers?
Last Answer : The hot water is sprayed from the top of the tower, while the air is made to flow from the bottom of the tower to the top. This air cools the hot water in the cooling tower. Air vaporises ... and leaves at the top of the tower and cooled water leaves at the bottom and recirculated to the condenser.
Description : What is meant by cooling Towers?
Last Answer : It is a tower or building like device in which atmospheric air circulates in direct or indirect contact with warmer water and water is thereby cooled. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid
Description : What consists of cooling water circuit and coal & ash circuit in steam power plant?
Last Answer : The cooling water circuit consists of a pump, condenser and cooling tower. The coal and ash circuit consists of coal delivery, preparation of coal, handling of coal to the boiler furnace, ash handling and ash storage.
Description : What are the types of oil used for in transformer for cooling?
Last Answer : Paraffin based and naphtha based (in INDIA)
Description : How selection of cooling fluid in GT done?
Last Answer : a) There are 5 factors are there. b) Density c) Coefficient of thermal expansion d) Viscosity e) Specific heat f) Thermal conductivity.
Description : How cooling is done for slip ring and brush gear?
Last Answer : A centrifuge fan is mounted on the shaft in between two slip rings for ventilation of the slip rings and brush gear.
Description : In MAPS Unit # 1 end-shield cooling system has got heaters. Why?
Last Answer : Unit # 1 end-shield is made of nickel steel, which had a nil ductility temperature of -100°C while commissioning. After 30 years of operation this will rise to +32°C, because of radiation exposure. ... #2 this problem is not existed because in this unit end-shields are made up of stainless steel.
Description : What you mean by cooling method?
Last Answer : Cooling method means elimination of heat from the fire.
Description : What is the cooling medium for different parts of the turbo generator?
Last Answer : Stator – DM water. Rotor – Hydrogen. Bearing – Oil.
Description : What are the types of cooling in transformer?
Last Answer : 1. Natural cooling. a. Air natural cooling (Dry type). b. Oil immersed natural cooling. c. Oil immersed, forced oil circulation with natural cooling. 2. Artificial cooling. a. Oil immersed forced ... This is the method of cooling combining oil natural, water, air natural, air blast and forced oil.