Chapter 4 Engine Basics
which of the following compression ratios would be typical of a current, turbo charged highway diesel truck?
16:1
how many times does a piston change direction during one complete diesel cycle?
4
What would be the highest thermal efficiency achievable in a current diesel engine?
40%
what is a typical compression achieved in a current highway truck diesel engine?
600psi
IF a diesel engine has a thermal efficiency of 35%, what percent of the heat energy of the fuel is discharged as rejected heat?
65%
The four stroked of the diesel cycle take place over
720 degrees
What is a typical compression ratio used on a current spark-ignited, gasoline fueled engines with indirect injection?
8:1
if an engine is run for maximum mechanical efficiency, where should peak cylinder combustion pressure be achieved?
Around 15 degrees ATDC
which of the following acronyms is used to describe an engine piston that is at the exact bottom of its travel?
BDC
Which of the following does most to define the piston stroke dimension?
Crank Throw Dimension
Which of the following is true of the term clearance volume?
Cylinder volume with piston at TDC
another way of saying Kinetic Energy
Energy of Motion
Four strokes in order of starting with the intake
Intake, Compression, Power, and Exhaust
Tech A says that valve overlap takes place as the piston completes its compression stroke. Tech B says that cylinder scavengine takes place at valve overlap. Who is correct?
Tech B only
What is another way of saying manifold boost?
Turbo boost
when does scavenging occur in the 4-stroke, diesel cycle?
Valve overlap
which is used to describe the overall breathing efficiency of an engine?
Volumetric efficiency
if an engine is described as square, what should be true
bore and stroke dimension are equal
If an engine is described as naturally aspirated, which of the following should be true?
there is no manifold boost
which of the following correctly defines piston swept volume
volume dislaced by piston through its stroke
