5) In a unit fuel-injection scheme,
PART III: Fill `er up!
6) Like the octane rating for gasoline, the cetane
number of a fuel is an indication of its ignition quality. Which
of the following statements is true?
7) Which of the following is false about the cetane
rating of a fuel?
PART III: General thermodynamics
8) The ratio of the heat equivalent of work done in
an engine to the total heat supplied in the same unit of time is
refereed to as its?
9) The ratio of brake horsepower output of an engine
to the indicated horsepower developed in the cylinders is called
the ________________ of the engine?
PART III: More advanced thermodynamics
10) A modern high-speed Diesel engine can best be
approximated by an ideal thermodynamic cycle with what characteristic?
11) Given a pair of engines of identical compression
ratios, displacements, etc., one operating on a ideal Diesel cycle
and the other an ideal (throttle-less) Otto cycle; which of the
following is a true statement?
12) A direct-injected Diesel engine typically has
a lower compression ratio but still achieves better fuel economy
and roughly equivalent cold-starting abilities (neglecting the contribution
of glow plugs) than an indirect-injected engine. Why?
13) What can be said of the thermal efficiencies in
real-world spark-ignition (SI engines)? Select one true statement:
14) What can be said of the thermal efficiencies in
real-world compression-ignition (CI engines)? Select one true statement:
15) A compression-ignition engine gets its improved
thermal efficiency over a spark-ignition engine because:
PART IV: Turbochargers
16) A well designed automotive turbocharger can achieve
about 75% isentropic (adiabatic) efficiency. Why aren't there devices
with 100% efficiency?
17) Which of the following statements is true?
18) What is the correct general rank of isentropic
efficiencies of the following various turbo- and supercharging schemes?
PART V: Cool-down
19) In general, how does the introduction of Exhaust
Gas Recirculation (EGR) in a Diesel engine affect thermal efficiency,
smoke output and emissions of Nitrogen Oxides (NOx)?
20) Catalytic converters: