更多"Scavenging is （） of exhaust gases b"的相关试题:
[单项选择]The process to remove exhaust gases by blowing in fresh air is called （）.
A. charging
B. supercharging
C. starting
D. scavenging
[单项选择]（） is the removal of exhaust gases by blowing in fresh air.
A. Gas exchange
B. Charging
C. Scavenging
D. Supercharging
[单项选择]Additional heat extraction from the exhaust gases can be effected by adding an （） section to the unit in plants.
A. air cooler
B. economizer
C. injector
D. air blower
[单项选择]Exhaust gases are generally removed from the cylinders of a two-stroke/cycle diesel engine by（）
A. natural aspiration
B. masked intake valves
C. air cells
D. scavenging air
[单项选择]Forcing the exhaust gases form the cylinder of an operating diesel engine with the aid of a blower is known as （）
A. scavenging
B. forced draft
C. turbo-charging
D. aspiration
[单项选择]The exhaust gases in a supercharged two-stroke/cycle diesel engine are expelled from the cylinder by （）
A. pumping action of the piston
B. pressure of the fuel charge
C. vacuum developed in the manifold
D. pressure of the fresh air charge
[单项选择]The exhaust gases for a new engine should be （） when the engine operates under full load.
A. smoky
B. a little bit dense
C. visible
D. almost invisible
[单项选择]Maintaining the lowest possible scavenging air temperature at all times is not recommended due to the possibility of the （）.
A. air charge density becoming too high
B. piston crown surfaces becoming too cold
C. formation of excessive quantities of condensate
D. compression pressure being greatly reduced
[单项选择]The principal difference between loop scavenging and crossflow scavenging, as used in single acting diesel engines, is the （）
A. direction of air flow within the cylinder
B. sequence of port opening
C. method of opening exhaust ports
D. volume of air admitted to the cylinder
[单项选择]The term diesel engine scavenging means（）
A. delivering more air into the cylinder than it would normally receive during an ordinary charging process
B. forcing the products of combustion out of the cylinder with the fresh air charge
C. collecting the air charge at the cleaner
D. combustion and expansion of hot gas
[单项选择]Clearance volume scavenging in a turbocharged, four-stroke/cycle diesel engine is accomplished （）.
A. during the valve overlap period
B. with only the exhaust valve open
C. at a pressure below atmospheric
D. without cooling the cylinders or pistons
[单项选择]In which of the scavenging methods listed will the exhaust valve be located in the cylinder head?（）
A. Return-flow
B. Uniflow
C. Cross-flow
D. Direct flow
[单项选择]Air scavenging of a diesel engine cylinder（）
A. blows out the exhaust gases
B. supplies oxygen for combustion
C. cools the valves and cylinder walls
D. all of the above
[单项选择]The scavenging box is built of a number of sections provided with vertical flanges enabling them （） together to form two blocks.
A. being bolted
B. bolted
C. bolting
D. to be bolted
[单项选择]Cross scavenging requires the fitting of （） to prevent air or exhaust gas escape when the piston is at the top of the stroke.
A. a exhaust valve
B. a piston skirt
C. a piston crown
D. an air suction valve
[单项选择]The scavenging air ports are located at （） that they are just exposed by the upper edge of the piston when the piston is in the bottom dead center position.
A. so a height
B. such a height
C. so high
D. such high
[单项选择]On top of scavenging air box is mounted a strong cast iron frame for each cylinder known as（）
A. cooling jacket
B. cylinder liner
C. piston crown
D. cylinder cover
[单项选择]Scavenging in a turbocharged, four-stroke/cycle diesel engine is accomplished（）
A. during the valve overlap period
B. with only the exhaust valve open
C. at a pressure below atmospheric
D. without cooling the cylinders or pistons
[单项选择]The process of scavenging a two-stroke/cycle diesel engine serves to（）
A. improve fuel flow volume
B. cool the exhaust valves
C. reduce the intake air charge density
D. increase the temperature of exhaust gases
