Internal Combustion Engines

Faculty - Er. Ashis Saxena

IndexUnit 1

Introduction to I.C EnginesFuels

Unit 2SI Engines

Unit 3CI Engines

Unit 4Engine CoolingLubricationSuperchargingTesting and Performance

Unit 5Compressors

Unit - 1

Chapter – 1(b)

Fuels

Fuels

Fuel is any material that is capable of releasing energy Fuel is any material that is capable of releasing energy

when its chemical or physical structure is changed or when its chemical or physical structure is changed or

converted. Fuel releases its energy either through converted. Fuel releases its energy either through

chemical means, such as burning, or nuclear means, chemical means, such as burning, or nuclear means,

such as nuclear fission or nuclear fusion. An important such as nuclear fission or nuclear fusion. An important

property of a useful fuel is that its energy can be property of a useful fuel is that its energy can be

stored to be released only when needed, and that the stored to be released only when needed, and that the

release is controlled in such a way that the energy can release is controlled in such a way that the energy can

be harnessed to produce work. be harnessed to produce work.

Types of Fuels

Fuels for engines are typicallyFuels for engines are typically

GaseousGaseous

LiquidLiquid

Originally solid also but now very rarely used.Originally solid also but now very rarely used.

They may also be classified as: They may also be classified as:

Naturally available orNaturally available or

Artificially derivedArtificially derived

Gaseous Fuels

Main fuels for engines areMain fuels for engines are

Natural gas – from natureNatural gas – from nature

Liquefied Petroleum Gas - from refineriesLiquefied Petroleum Gas - from refineries

Producer gas - from coal or biomassProducer gas - from coal or biomass

Biogas - from biomassBiogas - from biomass

Hydrogen – from many sourcesHydrogen – from many sources

Natural Gas

Found compressed in porous rock and shale Found compressed in porous rock and shale

formations sealed in rock strata underground.formations sealed in rock strata underground.

Frequently exists near or above oil deposits.Frequently exists near or above oil deposits.

Is a mixture of hydrocarbons and non-hydrocarbons Is a mixture of hydrocarbons and non-hydrocarbons

in gaseous phase or in solution with crude oil.in gaseous phase or in solution with crude oil.

Raw gas contains mainly methane plus lesser Raw gas contains mainly methane plus lesser

amounts of ethane, propane, butane and pentane, amounts of ethane, propane, butane and pentane,

negligible sulfur and organic nitrogen.negligible sulfur and organic nitrogen.

Some carbon dioxide and nitrogen are present.Some carbon dioxide and nitrogen are present.

Natural Gas: Facts

Existence of natural gas was known to people of ancient Greece, Existence of natural gas was known to people of ancient Greece,

India, and Persia, in the form of burning springs. These springs India, and Persia, in the form of burning springs. These springs

were created when fountains of natural gas, seeping out from were created when fountains of natural gas, seeping out from

cracks in the ground, were ignited due to lightning.cracks in the ground, were ignited due to lightning.

As per the data for 2006, Russia had the largest deposits of As per the data for 2006, Russia had the largest deposits of

natural gas (27%). Middle Eastern countries have a total of about natural gas (27%). Middle Eastern countries have a total of about

40% of the world's share of natural gas reserves, with Iran having 40% of the world's share of natural gas reserves, with Iran having

almost a 14% share.almost a 14% share.

There are over a million miles of gas pipelines laid, needed to There are over a million miles of gas pipelines laid, needed to

meet the energy needs of the US alone.meet the energy needs of the US alone.

It was used for the first time in the US in 1816, to light street It was used for the first time in the US in 1816, to light street

lights in Baltimore.lights in Baltimore.

Natural Gas: Facts

Over 90% of the gas requirements of the US are fulfilled from deposits Over 90% of the gas requirements of the US are fulfilled from deposits

found in the country itself.found in the country itself.

It is the third most widely used fuel in the US, after petroleum and coal.It is the third most widely used fuel in the US, after petroleum and coal.

According to the Energy Information Administration, natural gas According to the Energy Information Administration, natural gas

provides for 24% of the total energy needs of US.provides for 24% of the total energy needs of US.

More than 62% homes in the country rely on natural gas to run stoves, More than 62% homes in the country rely on natural gas to run stoves,

water heaters, furnaces and other home appliances.water heaters, furnaces and other home appliances.

Industries are the largest consumers of natural gas. Besides being used Industries are the largest consumers of natural gas. Besides being used

to produce energy by industries, natural gas is also used as an to produce energy by industries, natural gas is also used as an

ingredient in the manufacture of fertilizers, paints, ink and glue.ingredient in the manufacture of fertilizers, paints, ink and glue.

It can be used in fuel cells to produce electricity, in place of batteries. It can be used in fuel cells to produce electricity, in place of batteries.

This may increase the efficiency of electricity generation.This may increase the efficiency of electricity generation.

Natural Gas: Facts

Although natural gas pipelines and storage facilities have high Although natural gas pipelines and storage facilities have high

standards of safety, companies add a smelly substance to it, so that the standards of safety, companies add a smelly substance to it, so that the

leakage of this colorless, odorless gas can be identified.leakage of this colorless, odorless gas can be identified.

The energy content of natural gas is measured in terms of British The energy content of natural gas is measured in terms of British

Thermal Unit (BTU). One BTU is said to be the amount of heat required Thermal Unit (BTU). One BTU is said to be the amount of heat required

to raise the temperature of one pound of water by one degree to raise the temperature of one pound of water by one degree

Fahrenheit. In the US, however, retail sales are done in units of Therms. Fahrenheit. In the US, however, retail sales are done in units of Therms.

1 Therm = 1028 BTU.1 Therm = 1028 BTU.

Despite its various uses one of the major disadvantages of natural gas is Despite its various uses one of the major disadvantages of natural gas is

that it is highly combustible, due to which explosions are very likely.that it is highly combustible, due to which explosions are very likely.

The gas requires sophisticated treatment plants and underground The gas requires sophisticated treatment plants and underground

pipelines to be delivered to the site where it will be used. These pipelines to be delivered to the site where it will be used. These

installations are expensive and require high maintenance.installations are expensive and require high maintenance.

Use of Natural Gas as a fuel

Natural gas may be used asNatural gas may be used as

Liquefied Natural Gas (LNG).Liquefied Natural Gas (LNG).

Compressed Natural Gas (CNG).Compressed Natural Gas (CNG).

““Natural” gas when made artificially it is Natural” gas when made artificially it is

called substitute, or synthetic or supple-called substitute, or synthetic or supple-

mental natural gas (SNG).mental natural gas (SNG).

Natural Gas in Engines

When an engine was switched over to CNG from gasoline, the non-When an engine was switched over to CNG from gasoline, the non-

methane organic gases like CO and NOx, all reduced by 30-60%. methane organic gases like CO and NOx, all reduced by 30-60%.

Toxic emissions like benzene, butadiene and aldehydes were much Toxic emissions like benzene, butadiene and aldehydes were much

less than with gasoline.less than with gasoline.

Natural gas can replace diesel fuel in heavy-duty engines with the Natural gas can replace diesel fuel in heavy-duty engines with the

addition of a spark ignition system. Engines operate at addition of a spark ignition system. Engines operate at = 0.7 = 0.7

giving low in-cylinder temperatures and hence low NOx.giving low in-cylinder temperatures and hence low NOx.

Heavy-duty natural gas engines are designed to meet low emission Heavy-duty natural gas engines are designed to meet low emission

vehicle (LEV) emission standards without a catalytic converter and vehicle (LEV) emission standards without a catalytic converter and

will meet ULEV emission standards with a catalytic converter.will meet ULEV emission standards with a catalytic converter.

For heavy-duty applications, dual fuel operation is attractive, for For heavy-duty applications, dual fuel operation is attractive, for

buses, locomotives, ships, compressors and generators. buses, locomotives, ships, compressors and generators.

Natural Gas: Advantages

Is more environment friendly than oil or coal. It is largely because Is more environment friendly than oil or coal. It is largely because

of the fact that it has only one carbon and hence, produces less of the fact that it has only one carbon and hence, produces less

emissions. It is a known fact that for the same amount of heat it emissions. It is a known fact that for the same amount of heat it

emits 30% less carbon dioxide than burning oil, and 45% less emits 30% less carbon dioxide than burning oil, and 45% less

carbon dioxide than burning coal, thereby improving the quality carbon dioxide than burning coal, thereby improving the quality

of air.of air.

Is cheap (less expensive than gasoline) and therefore cost-Is cheap (less expensive than gasoline) and therefore cost-

effective. effective.

Can be safely stored and burned.Can be safely stored and burned.

The process of easily transporting natural gas over land through The process of easily transporting natural gas over land through

pipelines or over water bodies in the form of LNG (Liquid Natural pipelines or over water bodies in the form of LNG (Liquid Natural

Gas) is an added pro - it doesn't require high costs.Gas) is an added pro - it doesn't require high costs.

Natural Gas: Advantages

Most of its natural reserves are still underutilized.Most of its natural reserves are still underutilized.

Emits 60-90% less smog-producing pollutants.Emits 60-90% less smog-producing pollutants.

Natural gas becomes a primary source of electricity during Natural gas becomes a primary source of electricity during

situations when demand runs high.situations when demand runs high.

Due to the clean burning process, it doesn't produce ash after Due to the clean burning process, it doesn't produce ash after

energy is released.energy is released.

Has a high heating value of 24,000 Btu per pound.Has a high heating value of 24,000 Btu per pound.

It can provide as long as 24 hours of electricity throughout the It can provide as long as 24 hours of electricity throughout the

week, where other sources of its kind do not match up to its week, where other sources of its kind do not match up to its

endurance.endurance.

It is widely used as a primary source of heating whilst cookingIt is widely used as a primary source of heating whilst cooking

Natural Gas: Disadvantages

Because it is a non renewable source of energy, its availability is finite. Critics Because it is a non renewable source of energy, its availability is finite. Critics

also point out that its extraction leaves large craters within the earth.also point out that its extraction leaves large craters within the earth.

Is highly volatile (highly flammable), and can be dangerous if handled Is highly volatile (highly flammable), and can be dangerous if handled

carelessly.carelessly.

In gas pipelines, a substance (contains carbon monoxide) that has a strong In gas pipelines, a substance (contains carbon monoxide) that has a strong

odor is added to help detect a leak. But such substances may be harmful and odor is added to help detect a leak. But such substances may be harmful and

cause deaths if not carefully handled. In fact, natural gas is the most common cause deaths if not carefully handled. In fact, natural gas is the most common

cause of carbon monoxide deaths.cause of carbon monoxide deaths.

Constructing and managing transportation pipelines costs a lot if not the Constructing and managing transportation pipelines costs a lot if not the

transporting of the substance itself.transporting of the substance itself.

While it may give off lesser carbon dioxide than other sources of energy, it is While it may give off lesser carbon dioxide than other sources of energy, it is

nonetheless damaging the ecosystem.nonetheless damaging the ecosystem.

It isn't used in vehicles as a primary source of fuel since it is a highly It isn't used in vehicles as a primary source of fuel since it is a highly

combustible substance.combustible substance.

Natural Gas: Constituents

CNG vs Automotive fuels

CNG vs Automotive fuels

Composition of typical crude oil

Refining of crude oil

Product Boiling Range, oCLiquefied Petroleum Gas 40 to 0

Motor Gasoline 40-200

Kerosene, jet fuel (ATF) 170-270

Diesel Fuel 180-340

Furnace Oil 180-340

Lube Oils 340-540

Residual Fuel 340-650

Asphalt 540+

Petroleum Coke Solid

Refining of crude oil

Qualities of SI engine fuels

Qualities of SI engine fuels

Qualities of SI engine fuels

Qualities of CI engine fuels

Qualities of CI engine fuels

Qualities of CI engine fuels

Rating of engine fuels

Rating of SI engine fuels (Gasoline)

Octane Rating

Rating of CI engine fuels (Diesel) – Cetane rating

Alternate Fuels - Propane

Alternate Fuels – Alcohol & Hydrogen

Alternate Fuels - Biodiesel

Alternate Fuels - LPG

Alternate Fuels - LPG

Alternate Fuels - CNG

Alternate Fuels - CNG

Alternate Fuels - LNG

Alternate Fuels - LNG

Dopes & Additives for fuels

Dopes for SI engine fuels contd…

Dopes for SI engine fuels contd…