单选题Directional intake ports in diesel engines are used to （）.Areduce air charge turbulenceBinduce air swirlCdeflect hot combustion gas away from the valvesDoppose the effects of piston induced squish
单选题
Directional intake ports in diesel engines are used to （）.
A
reduce air charge turbulence
B
induce air swirl
C
deflect hot combustion gas away from the valves
D
oppose the effects of piston induced squish
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