单选题Air motion is induced in a four-stroke/cycle diesel engine cylinder to improve air fuel mixing, and is known as（）AsuperchargingBscavengingCturbulenceDswept volume charging
单选题
Air motion is induced in a four-stroke/cycle diesel engine cylinder to improve air fuel mixing, and is known as（）
A
supercharging
B
scavenging
C
turbulence
D
swept volume charging
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