alcohol as an alternative fuel in s 2
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Alcohol as an alternative
fuel in S.I Engine
MANORANJAN NAYAK
1101219528
COLLEGE OF ENGEERING,
BHUBANESWAR
OUTLINE
INTRODUCTION
E85 FUEL BLENDED
ETHANOL
BLENDING
POWER MAKING FUEL CHARACTERISTICS
FLEXIBLE FUEL VEHICLE
ALCOHOL FUMIGATION
ADVANTAGES
DISADVANTAGES
APPLICATION
INTRODUCTION
In this century, it is believed that crude oil and petroleum products will
become very scarce and costly.
Day-to-day, fuel economy of engines is getting improved and will
continue to improve. However, enormous increase in number of
vehicles has started dictating the demand for fuel.
With increased use and depletion of fossil fuels, alternative fuel
technology will become more common in the coming decades.
Because of the high cost of petroleum products, energy security ,
emission problems some developing countries are trying to use
alternate fuels for their vehicles
LIQUID FUELS:
Liquid fuels are preferred for IC engines because they are easy to store and
have reasonably good calorific value. The main alternative is the alcohol
ALCOHOL:
Alcohols are attractive alternate fuels because they can be obtained from both
natural and manufactured sources. Methanol and ethanol are two kinds of
alcohols that seem most promising.
E85,alcohol fuel mixture of 85% ethanol and
15% gasoline E85 is an alcohol fuel mixture of 85% ethanol and 15% gasoline, by
volume. ethanol derived from crops (bioethanol) is a biofuel.
E85 as a fuel is widely used in Sweden and is becoming increasingly
common in the United States, mainly in the Midwest where corn is a
major crop and is the primary source material for ethanol fuel
production.
E85 is usually used in engines modified to accept higher concentrations
of ethanol. Such flexible-fuel engines are designed to run on any mixture
of gasoline or ethanol with up to 85% ethanol by volume.
HOW IS IT MADE NOW?
HISTORICALLY MADE FROM CORN AND OTHER STARCH SOURCES OR FROM NATURAL SUGARS BY FERMENTATION
COMMON SOURCES INCLUDE RICE, POTATO, CASSAVA – PLUS CORN AND OTHER GRAINS
MANUFACTURING PROCESS WAS VERY ENERGY-INTENSIVE, BUT IS NOW LESS SO IN MOST MODERN PLANTS, DUE TO ADVANCES IN DISTILLATION TECHNOLOGY
Ethanol
Closed carbon dioxide greenhouse gas cycle for biofuels.
Ethanol & biodiesel are sustainable forms of solar energy.
What about Using Ethanol for Fuel?
BLENDING Automobile fuels be “oxygenated” in order to reduce air pollution.
In addition, removal of lead from gasoline renewed interest in ethanol as
octane booster.
While E10/E15 is intended for all automobiles, a blend called “E85” is
intended for flex fuel vehicles. E85 is nominally 85% ethanol and 15%
gasoline, albeit it can be as high as 30% gasoline in cold climates in
winter.The principle reason for blending some gasoline into ethanol for flex
fuel vehicles is to improve starting in cold weather.
Ethanol is separated from the water in which it is produced via a process
called distillation. The distillation process does not remove all of the water.
Having some water mixed in with the fuel is actually improves performance
of an internal combustion engine, as the water provides extra mass to
absorb the heat of combustion and turn it into high pressure steam for
mechanical energy.
However, water and gasoline don’t mix well (are not “miscible”, in
chemical terms), sothe water must be removed when producing ethanol-
gasoline blends. This dry or “anhydrous” ethanol is needed to prevent
phase separation of the fuel components in ethanol - gasoline blends.
Power Making Fuel Characteristics
1.Octane Rating [MON]
2.Burning Rate
3.Latent Heat of Vaporization
[kJ/kg]
4.Energy Value [MJ/kg]
&
5.Reduction in Green house gases
1. ne Rating
2. Burning Rate800-597-9747 www.iqlearningsystems.com
1. Octane
Measures fuel’s resistance to pre-
ignition and detonation, commonly
called “knocking”
Three common octane ratings for
motor fuels: Research Octane Number (RON)
Motor Octane Number (MON)
(R+M/2) method
800-597-9747 www.iqlearningsystems.com
1. Octane (cotd.)
MON rating is most useful to racers
because it is measured under high
loads and at high RPM’s
High MON rated fuels allow the use of
higher compression and advanced
spark timing
E85 delivers MON octane ratings
equal to, or better than, most
gasoline800-597-9747 www.iqlearningsystems.com
2. Burning Rate
The speed at which fuel burns and releases
its heat energy
There is less time for fuel to burn at high
RPM’s, so rapid burning fuel is a must in
racing
Peak horsepower (kW) and engine
efficiency are realized if fuel is almost
completely burned by 20 degrees after Top
Dead Center (TDC)
800-597-9747 www.iqlearningsystems.com
3. Latent Heat of Vaporization
Measures a fuel’s ability to cool the
intake charge and combustion chamber
Measured in kJ/ lt.
Higher rated fuels remove heat better
800-597-9747 www.iqlearningsystems.com
3. Latent Heat of Vaporization
E85 promotes better cooling:
Making the intake charge more dense,
thereby packing more energy (per
volume) into the engine
Helping to control detonation
Reducing temperatures in the engine
and oiling system components
800-597-9747 www.iqlearningsystems.com
4. Energy Value
The total heat energy contained in a given
amount of fuel – kJ/kg
Horsepower generation depends on “Net
Energy Value” - Equal to the energy value
multiplied by the amount of fuel that can be
burned
A fuel’s “stoichiometric” defines its ideal
air/fuel ratio
Lower stoichiometric fuels allow more fuel to
be burned which, in turn, increases the Net
Energy Value of the fuel800-597-9747 www.iqlearningsystems.com
Ethanol and Flexible Fuel Vehicles (FFVs)
What is a FFV?
• FFVs are specially designed to run on all ethanol blends up to 85%
• FFVs can use any mixture of gasoline or E85
• FFVs have fuel sensors which
monitor ethanol/gasoline ratios
Property Ethanol Gasoline (87 Octane) E85
Octane (R+M)/2 98-100 86-94 96
Lower Heating Value(Btu/lb) 11,500 18,000-19,000 12,500
Gallon Equivalent 1.5 1 1.4
Miles per Gallon vs. Gasoline 70% 100% 72%
Relative tank size to yield Tank is 1.5 times 1 Tank is 1.4 times
(Driving range equivalent to gasoline) Larger Larger
Reid Vapor Pressure (PSI) 2.3 8 to 16 6 to 12
Specific Gravity (@ 60/65 F) 0.794 .72-.78 0.78
Cold Weather Starting Poor Standard As good as gasoline
Vehicle Power 5% Increase Standard 3%-5% Increase
Air/Fuel Ratio (by weight) 9 14.7 10
Ethanol & E85 vs. Gasoline
Flexible Fuel Vehicle
Flexible Fuel Vehicles, also known as FFVs, are designed to run on
gasoline, E85, or any combination of the two. The “Flexible” nature
of the vehicle gives the driver the flexibility to switch back and forth
between gasoline and E85.
Ethanol contains more oxygen than gasoline. The vehicles come equipped with an oxygen sensor which determines the amount of
ethanol in the fuel at any time. It provides this information to the
onboard computer, which then adjusts the engine to maximize
efficiency and performance. The fuel may contain anywhere from
zero to 85% ethanol. FFVs are widely available and include sedans,
minivans, SUVs, and pickup trucks.
Utilization of Alcohol Fuels in
Compression Ignition engines difficulties encountered:-
1.More alcohol fuel than diesel fuel is required by mass and volume.
2.Large percentages of alcohol do not mix with diesel fuel, hence use of diesel-alcohol blends is not feasible .
3.Alcohols have extremely low cetane numbers, whereas the diesel engine is known to prefer
4.Diesel fuels serve as lubricants for diesel engine. Alcohol fuels do not have the same lubricating qualities.
5. The poor auto-ignition capability of alcohols is responsible for severe knock due to rapid burning of vaporized alcohol.
Alcohol Fumigation
Fumigation is a method by which alcohol is
introduced into the engine by carbureting,
vaporizing or injecting the alcohol into the
intake air stream. This requires the addition
of a carburetor, vaporizer or injector, along
with a separate fuel tank, lines and controls.
Fumigation has some following advantages:
It requires a minimum of modification to the engine.
The engine can switch from dual fuel to diesel fuel operation and vice-
versa by disconnection and connection of the alcohol source to the
injector.
If an engine is limited in power output due to smoke emissions, fumigated
ethanol could increase the power output because alcohol tends to
reduce smoke. This is because of good mixing of the injected charge with
alcohol.
Fumigation can substitute alcohol for diesel fuel. Up to 50% of the fuel
energy can be derived from alcohol by fumigation
It is a high octane fuel with anti-knock index numbers of over 100.Engines using high octane fuel can run more efficiently by using higher compression ratios. Alcohols have higher flame speed.
It produces less overall emissions compared to gasoline.
When alcohols are burned, it forms more moles of exhaust gases, which gives higher pressure and more power in the expansion stroke.
It has high latent heat of vaporization which results in a cooler intake process. This raises the volumetric efficiency of the engine and reduces the required work input in the compression stroke.
Alcohols have low sulphur content in the fuel.
Reduced petroleum imports and transportation.
ADVANTAGES:
Alcohols have low energy content or in other words the calorific value of the fuel is less.
With equal thermal efficiency and similar engine output usage, twice as much fuel would have to be purchased.
Even with the low energy content of the fuel, engine power for a given displacement would be about the same. This is because of the lower air-fuel ratio needed by alcohol.
Alcohol contains oxygen and thus requires less air for stoichiometric combustion. More fuel can be burned with the same amount of air.
Alcohol is much more corrosive than gasoline on copper, brass, aluminum, rubber, and many plastics. This puts some restrictions on the design and manufacturing of engines to be used with this fuel. Methanol is very corrosive on metals.
It has poor cold weather starting characteristics due to low vapor pressure and evaporation.(E85 rectifies it)
DISADVANTAGES:
BRAZILWorld leader in production and export of ethanol.
Ethanol produced per day equivalent to 200,000
barrels of gasoline.
24% blend ethanol mandatory.
Competitiveness
Bio diesel initiatives underway
U.S.A.Ethanol : a big boost to economy
E85 sells cheaper than gasoline
Currently production aimed at 4.5 Billion
gallons/yr
IndiaSources of ethanol:
Sugarcane,Molasses&Agricultural waste
Low average cost of Rs.18/litre projected
Annual production capacity of 1.5 Billion litres
APPLICATION
Extensive research and development is difficult to justify until
the fuels are accepted as viable for large numbers of engines.
Most alternate fuels are very costly at present since the
quantity used is very less.
There is lack of distribution points (service stations) where fuel is
available to the public.
DIFFICULTIES
CONCLUSION
I Would sum up the whole presentation into few lines saying that
reducing fossil fuels in the near future would be a great loss to mankind
if we are not able to find out any alternative for it and I found alcohol
to be effective as it can be produced easily and the flexible fuel vehicle will be proved to be of great advantage.
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