ch7

Question 1

what causes high turbulence?

Answer 1

high velocity, bad for scavenging bc intake and exhaust mixes

Question 2

Swirl

Answer 2

Main bulk rotational motion inside a cylinder

Question 3

swirl ratio (list both)

Answer 3

Angular (engine speed)
Tangential (average piston speed)

Question 4

squish

Answer 4

Inward flow as piston approaches TDC (clearance volume mostly in center) that promotes air-fuel mixing (good)

Question 5

tumble

Answer 5

secondary rotational motion in piston face contours that promotes stratification (good) to
allow lean mixtures to combust

Question 6

crevice

Answer 6

Numerous small secondary volumes in the high-pressure cylinder (e.g. spark plug threads)
that’s minimized and accounts for 1% to 3% of volume

Question 7

blowby

Answer 7

Gas that get past the piston into the crankcase

Question 8

divided combustion chambers?

Answer 8

secondary chamber holds rich mixture near sparkplug. con: causes more heat transfer

Question 9

What are three (3) types of motions within the combustion chamber?

Answer 9

swirl, tumble, squish