Internal Combustion Engine - CHAPTER 9

Locate converter close to engine

does heat it as quickly as possible after the engine is started

Thermal battery

energy from a thermal storage system

Atmospheric nitrogen

exists as a stable diatomic molecule at low temperatures.

Quenching

in terms of combustion refers to extinguishing a flame

Oil

is a high molecular weight hydrocarbon compound that does not burn as readily as gasoline

Cyanuric acid

is a low-cost solid material that sublimes in the exhaust flow.

Two stroke oil

is a special type of motor oil intended for use in crankcase compression two stroke engines.

Catalyst

is a substance that accelerates a chemical reaction by lowering the needed for it to proceed

NOx

is a very undesirable emission

TEL

is also known as Tetraethyl lead

Ammonia

is an undesirable emission

Exhaust gas recycle

is done by ducting some of the exhaust flow back into the intake system.

Photochemical smog

is form when HC emission get into the atmosphere and react with atmospheric gases.

Maximum Carbon Monoxide

is generated when an engine runs rich

Ground-level ozone

is harmful to lungs and other biological tissue.

Monoatomic Oxygen

is highly reactive and initiates a number of different reactions.

Catalytic converter

is the most effective after treatment system for reducing engine emission

Durability

is the serious limitation using zeolite molecular sieves method

Crevice volume

is the space between the Cylinder wall and the piston

Valve Seat

is the surface against which an intake or an exhaust valve rests during the portion of the engine operating cycle when that valve is closed

Valve

is usually a flat disk of metal with a long rod

Blowby gas

is very high in hydrocarbon

Vanous method

it is used when soot build up becomes excessive and regeneration is needed

ppm

means " parts per million"

Engine Misfire

means that car's engine skip over one of the process of its combustion cycle.

TRUE

modern high compression engines could not use low octane fuel.

1990s

more fuel efficient engines we developed so the average automobile consume less than half the fuel used in 1970s

incomplete combustion

occur when there is not enough oxygen to allow the fuel to react completely.

Over 90%

of carbon particles originally generated within an engine are thus consumed and never get exhausted.

10%-50%

of the lead exhausted out with the other combustions products.

Lead

one of the major pollutant was phase out as a fuel additive in 1980s

3%

percentage of fuel in the chamber can be forced into the crevice volume

Platinum

promote exidation of CO and HC

Palladium

promote oxidation of CO and specially HC

Sulfur

promote the conversion of SOz to SO3

Rhodium

promote the reaction of NOx

Emissions

rate of a given pollutant from a given source.

Hydrocarbon emissions

result from the presence of unburned fuel in the exhaust of an engine

Dual fuel engines

run on a combination of gasoline and methanol (0-85%)

EMS

stands for engine management system

EGR

stands for exhaust gas recycle.

2500 - 3500K

temperature range that can exist in an engine

Modern two-stroke cycle engine

that uses fuel injection have cooler exhaust because of their high efficiency and lean operation.

PCV (positive crankcase ventilation) system

the first effort at controlling pollution from automobiles

Pressure

the formation of NOx depends on ____.

Increase gasoline octane number

the used of Tetraethyl lead

Phosphorus

these come from impurities in the air and small amounts in some fuel blends and lubricating oil.

Cold start-ups

when an engine is started after not being operated for several hours

Engine start and warm up

where Hydrocarbon emissions are greatest

The simplest way to reduce NOx emissions is to hold the combustion chamber temperature down.

The simplest way to reduce NOx emissions is to hold the combustion chamber temperature down.

Soluble Organic Fraction

This absorbed portion of the soot particles

20%

This accounted for up to ____ of total emission because of the crankcase breather tube being vented out to the atmosphere

valve overlap

both the exhaust and intake valves are open

Nitrogen

can also be found in fuel blends

NH3

chemical formula of ammonia

Unleaded gasoline

contains 150 - 600 ppm sulfur by weight

Diesel Fuels

contains up to 5000 ppm sulfur by weight

0.15gm/liter

- the leaded gasoline contains about ______ of lead in the fuel

A very rich mixture there is not enough oxygen to react with all the carbon, resulting in high levels of HC in the exhaust products

A very rich mixture there is not enough oxygen to react with all the carbon, resulting in high levels of HC in the exhaust products

1940s

Air pollution was First recognized as a problem in Los Angeles, California

Ammonia injection systems are not practical in automobiles or on other smaller engines

Ammonia injection systems are not practical in automobiles or on other smaller engines

Respiratory Irritant

Any substance which can cause inflammation or other adverse reactions in the respiratory system.

CO also known as carbon monoxide

CO also known as carbon monoxide

Chemical reaction preheating uses the heat liberated from an exothermic chemical reaction

Chemical reaction preheating uses the heat liberated from an exothermic chemical reaction

Very low CO emission

Cl engines that operate overall lean generally have ______.

1960s

Emission Standard were beginning to be enforced California

Exhaust gases leaving the combustion chamber of an SI engine contain up to 6000 ppm(parts per million) of hydrocarbon component, the equivalent of 1 - 1.5% of the fuel.

Exhaust gases leaving the combustion chamber of an SI engine contain up to 6000 ppm(parts per million) of hydrocarbon component, the equivalent of 1 - 1.5% of the fuel.

2000 ppm

Exhaust gases of an engine can have up to _____ of oxides of nitrogen

HC also known as hydrocarbon

HC also known as hydrocarbon

Spark plug

HC emissions can be reduced if a second ________ is added to an engine combustion chamber

Unlead Fuel

Harder metals and added surface treatments are used for engines designed to use ______________.

1980s

Lead was phased out in the _______.

Lean burn engines uses stratified charge

Lean burn engines uses stratified charge

Under Load

Maximum density of particulate emissions occurs when the engine is ____ at WOT.

NOx also know as nitric oxide

NOx also know as nitric oxide

Nitrogen

NOx is created mostly from ___ in the air

No EGR is used at idle and very little at low speeds.

No EGR is used at idle and very little at low speeds.

No EGR is used during WOT, when maximum power is desired.

No EGR is used during WOT, when maximum power is desired.

Reactive

Other gases that are stable at low temperatures but become ___ and contribute to the formation of NOx at high temperatures include water vapor and oxygen

Ozone

Released NOx reacts in the atmosphere to form ____ and one is of the major causes of photochemical smog.

Higher exhaust temperature can be caused by

Stoichiometric Air - Fuel Combustion High Engine Speed Retarded Spark Low expansion Ratio

Flow rate of EGR

The ____ is controlled by the EMS.

30%

The amount of EGR flow can be as high as ____ of the total intake.

The farther the sparkplug is from the ring gap , the greater the HC in the exhaust

The farther the sparkplug is from the ring gap , the greater the HC in the exhaust

95%

____ NOx reduction has been achieved using cyanuric acid.

Carbon Monoxide

a colorless, odorless, poisonous gas, is generated in an engine

Flame heating

a flame is initiated in the burner using fuel air pumped from external sources

Crankcase breather tube

a major source of HC emissions that was vented out to the atmosphere at old automobiles.

Solid carbon soot

a problem unique to CI engines when using EGR.

Superinsulation

accelrate the temperature rise to steady-state condition

Electric heating

allows much quicker heating by means of thermal conduction

Chemical Radicals

an atom, molecule, or ion that has an unpaired valence electron

Soot particles

are clusters of solid carbon spheres

Carbon spheres

are generated in the combustion chamber in the fuel-rich zones

Thermal Converter

are high temperature chambers through which the exhaust gas flows

Zeolite molecular sieves

are materials that absorb selected molecular compounds and catalyze chemical reactions.

Thermal Converter

as a means of lowering emissions

1%

as much as ____ of fuel was vented to the atmosphere through the crankcase breather in some automobiles.

TRUE

at high temperatures the sulfur combines with hydrogen to form Hydrogen Sulfide and in oxygen to form Sulfur Dioxide

Photochemical Smog

becomes a major problem in many large cities in the whole world