Diesel-Chapter 1: Introduction to Diesel Engines

Otto cycle

an engine operating cycle consisting of fuel lean and air rich

power density

The power an engine produces for its displacement

Renewable Fuel Standard (RFS)

Legislation that requires the use of more biologically based fuels from renewable sources

particulate matter (PM)

a category of noxious emissions made up of liquid or solid particles. Black exhaust soot is a common PM emission

compression-ignition (CI)

a combustion mechanism that ignites fuel by using the heat derived from compressing air as an ignition source

thermal efficiency

a comparision between the amount of energy released during combustion and energy available at the engine flywheel

compression ratio

a comparison between total cylinder volume and clearance

biodiesel

a fuel derived from a plant or animal source

common rail

a high-pressure injection system that electronically varies injection pressure, timing, and rate.

ton-miles per gallon

a measure used for new fuel efficiency standards that is calculated by measuring the vehicle weight in tons, multiplying the distance traveled in miles, and then dividing the volume of fuel consumed measured in gallons. The metric equivalent of ton-miles per gallon is grams per ton

torque

a measurement of rotational, or twisting, force transmitted from the crankshaft to the flywheel

plasma catalytic converters

a new catalytic converter technology that uses high-frequency alternating current to destroy noxious missions in the exhaust system

down speeding

a strategy that takes advantage of a diesel engine's high torque output at low engine speeds by lowering drive axle gear ratios. The engine operates at lower rpm while operating at highway speeds

selective catalyst reduction (SCR)

an exhaust aftertreatment technology that targets and breaks down NO emissions

diesel particulate filter (DPE)

an exhaust emission after-treatment device that filters soot particulate from the exhaust stream

lean burn combustion

combustion that uses an excess amount of air to burn fuel. The cylinder is considered fuel lean and air rich

useful life requirement

emissions legislation that requires an engine to remain below maximum emission thresholds for its normal expected service life

turbocharger

exhaust-driven device that compresses air to pressurize the air intake of an engine

greenhouse gas

gases that are believed to contribute to global warming

torque elasticity

the ability of an engine to produce the torque needed to accelerate from medium to high engine speed while under load

top dead center (TDC)

the highest point the piston travels in a cylinder