更多"A waste heat boiler is installed on"的相关试题:
[单项选择]Diesel engine waste heat boiler construction is usually of the fire-tube or（）
A. cyclone furnace boiler type
B. dry back boiler type
C. water-tube type
D. critical circulation boiler type
[单项选择]The purpose of designing some waste heat boilers with sinuous fire tubes, is to（）
A. increase exhaust gas velocity through the boiler
B. reduce accumulations of carbon deposits on the heat transfer surfaces
C. eliminate exhaust gas pulsations and noise
D. increase the rate of heat transfer to the waterside
[单项选择]Generating tubes in waste heat boilers are finned to （）.
A. reduce gas flow turbulence
B. prevent exhaust gas corrosion
C. increase the rate of combustion
D. increase the rate of heat transfer
[单项选择]The interior of some diesel engine saltwater heat exchangers are protected from corrosion by the use of（）
A. aluminum plates
B. lead cathodes
C. copper baffle plates
D. sacrificial zincs
[单项选择]The maximum pressure developed by a waste heat boiler is determined by the main engine exhaust （）.
A. gas composition
B. gas temperature
C. pressure
D. timing
[单项选择]An exhaust gas bypass is installed on a waste heat boiler in order to （）.
A. bypass exhaust gas at high loads to prevent excessive back pressure
B. bypass a portion of the exhaust gas at peak loads for better efficiency
C. recycle exhaust gas to the turbocharger
D. minimize moisture condensation in the boiler gas passages at low loads
[单项选择]A SECONDARY function of a waste heat boiler is to （）.
A. reduce engine exhaust noise
B. reduce engine back pressure
C. increase engine cycle efficiency
D. increase turbocharger efficiency
[单项选择]The PRIMARY function of a waste heat boiler is to （）
A. reduce engine exhaust noise
B. reduce engine back pressure
C. recover heat which otherwise would be lost
D. increase turbocharger efficiency
[单项选择]In a diesel engine, offers the heat energy directly（）； works as working medium and changes the heat energy to mechanical energy（）
A. the burning of the fuel； medium shaft
B. fuel spray； fresh air
C. fuel； fuel spray
D. the burning of the fuel； the burned gas mixture
[单项选择]In a diesel engine, the time taken to heat the fuel particles, turn them into vapor, and bring about combustion is called （）
A. injection lag
B. ignition delay
C. compression
D. turbulence lag
[单项选择]Why are some diesel engine cylinder liners plated on the wearing surface with porous chromium?（）
A. The chromium will not wear out the piston rings
B. The chromium strengthens the liners in the way of the scavenging air ports
C. Chromium eliminates the need for oil scraper rings
D. Pores in the plating aid in maintaining the lube oil film
[单项选择]Some diesel engines are fitted with a thermometer in the cooling water outlet from each cylinderIf the cooling water temperature from all cylinders begins to rise above normal, you should suspect （）
A. increase blow-by in all cylinders
B. incomplete combustion in all cylinder
C. overloading in all cylinders
D. insufficient fuel delivery to all cylinders
[单项选择]An electric heater built into some smaller diesel engines is used to （）.
A. raise lube oil viscosity for easier starting in cold weather
B. increase air inlet temperature
C. increase compression ratio
D. increase jacket water temperature for easier starting in cold weather
[单项选择]Some diesel engines are supercharged with a （）
A. slam charger
B. turbocharger
C. fuel atomizer
D. fuel injector
[单项选择]Valve cages are used on some large diesel engines to （）
A. reduce wear on the valve stem
B. permit the use of alloy valve seat materials
C. reduce heat transfer from the valve seat
D. facilitate valve removal for servicing
[单项选择]Some medium and high-speed diesel engines require reduction gear units to provide a useful propeller speedIn most reduction gears, the bull gear（）
A. must churn the oil in the sump
B. is connected to the propeller shaft
C. is driven at the highest RPM
D. compensates for alignment variations between the engine and pinion gear
[单项选择]In some modern large diesel engines, which of the following is used as the support for the main bearings?（）
A. Bedplate
B. Block
C. Base
D. Sump
[单项选择]In some diesel engine designs,（）the injection of cylinder oil is timed to impinge when the piston and only impinge on（）
A. is coming upward；cylinder ring belt
B. is going downward；piston ring belt
C. is coming upward；piston ring belt
D. is going downward；cylinder ring belt
