Refimprove date October 2008 Airfuelratio AFR is the mass ratio of air to fuel present in an internal combustion engine . If exactly enough air is provided to completely burn all of the fuel, the ratio ... and high load conditions, a richer mixture lower airfuelratio is used to produce cooler combustion ... mixes. Vehicles using oxygen sensor s enable the airfuelratio to be monitored by means of an airfuelratio meter . Other types of engine In the typical air to natural gas combustion burner, a double ... gas air or fuel .This assures ratio control within an acceptable margin. Other terms used There are other terms commonly used when discussing the mixture of air and fuel in internal combustion engines ... manuals in the aviation world. Airfuelratio AFR The airfuelratio is the most common reference term used for mixtures in internal combustion engines. math AFR frac m air m fuel math It is the ratio ... 1 or of 0.850 to 0.901. Fuelairratio FAR Fuelairratio is commonly used in the gas turbine ... of fuel to the air. fact date October 2011 math FAR frac 1 AFR math Lambda Lambda is the ratio of actual ... thumb Ideal stoichiometry See also Adiabatic flame temperature AFR sensor Airfuelratio ... article.jsp?pubId 1&id 1171 accessdate 2009 03 18 DEFAULTSORT AirFuelRatio Category Chemical ... just enough air to completely burn the available fuel. In practice this is never quite achieved, due ... if the engine is placed under high load at this fuelair mixture. Due to the high temperatures at this mixture, detonation of the fuelair mix shortly after maximum cylinder pressure is possible under ... damage as the uncontrolled burning of the fuelair mix can create very high pressures in the cylinder ... to achieve in light load cruise situations. For gasoline fuel, the stoichiometric airfuel mixture ... in liquid form that is released at time of combustions for MTBE laden fuel, a stoichiometric ratio ... to air ratios usually by controlling fuel volume will usually compensate automatically for this change ... more details
Unreferenced date February 2012 An airfuelratio meter monitors the airfuelratio of an internal combustion engine . Also called airfuelratio gauge , airfuel meter , or airfuel gauge . It reads the voltage ... meters that stand alone or are mounted in housings. Nearly all of these show the airfuelratio on a numeric ... more accurate electronics, these meters are more expensive. Benefits of airfuelratio metering Determining the condition of the oxygen sensor A malfunctioning oxygen sensor will result in airfuel ... fuel mixture is approximately 14.7 times the mass of air to fuel for gasoline. This ratio maintains ... hand, has a very linear output, 0 5 V, and is not temperature dependent. Which type of airfuelratio meter to be used If the purpose of the airfuelratio meter is to detect also an existing or possible ... airfuelratio meter is sufficient. In high performance tuning applications, the wide band system .... The leaner the airfuel mixture, the higher the combustion temperature is inside the cylinder. Too ... fuel does not vaporize as well when cold and therefore requires more fuel to properly saturate the air ... of the airfuel mixture. As mentioned above, there are two types of sensors available narrow band ... lead to increased fuel consumption and increased pollutant emissions as well as decreased power and throttle response. Reducing emissions Keeping the airfuel mixture near the stoichometric ratio of 14.7 1 for gasoline engines allows the catalytic converter to operate at maximum efficiency. Fuel economy in automobiles Fuel economy An airfuel mixture leaner than the stoichiometric ratio will result in near optimum fuel mileage, costing less per mile traveled and producing the least amount of CO ... ratio rather than as lean as possible while remaining driveable , to maximize the efficiency and life ... ratio, manufacturers must focus on emissions and especially catalytic converter life which ... priority due to U.S. EPA regulations. Car tuning Engine performance Carefully mapping out air ... more details
Technical date June 2008 Tissue AirRatio TAR is a term used in radiotherapy treatment planning to help calculate absorbed dose to water in conditions other than those directly measured. Definition The TAR at a point in a water phantom irradiated by a photon beam is taken to be the ratio of the total absorbed dose at that point to the absorbed dose at the same point in a minimal scatter phantom with just sufficient build up ref Hendee W., Ibbott G. and Hendee E. 2005 . Radiation Therapy Physics . Wiley Liss Publ. ISBN 0 471 39493 9. ref . Tissue airratio is defined as the ratio of the dose to water at a given depth to the dose in air measured with a buildup cap. Measurements for each are taken using an ion chamber for identical source to detector distances and field sizes. ref Faiz M. Khan. 2010 The Physics of Radiation Therapy Lippencott, Wilkins and Williams Publ. ref See also Dosimetry Percentage depth dose curve References reflist DEFAULTSORT Tissue To AirRatio Category Radiation oncology Category Medical physics ... more details
The air to cloth ratio is the volumetric flow rate of air m minute Systeme International SI m second flowing through a dust collector s inlet duct divided by the total cloth area m in the filters. The result is expressed in units of velocity . math v V Delta t over A math The air to cloth ratio is typically between 1.5 and 3.5 metres per minute , mainly depending on the concentration of dust loading. External links http www.usairfiltration.com dust collectors dust collector terminology.htm Details on how to calculate air to cloth ratio Category Filters Category Engineering ratios zh ... more details
A Magnesium AirFuel Cell MAFC is a type of fuel cell which uses a magnesium anode , oxygen from air as a cathode and a salt water electrolyte . ref cite web url http www.physorg.com news191259549.html title Magnesium Alternative Power Source author Messina, John date 2010 04 23 ref Research and commercialization of the technology by http www.magpowersystems.com MagPower Systems has shown an efficiency of 90 and an operating range of 20 to 55 degrees Celsius. ref cite web url http www.magpowersystems.com mafc hfc title MAFC verses HFC Hydrogen Fuel Cell ref Fuel cells References Reflist Category Fuel cells Category Sustainable technologies Energy stub ja ... more details
September 2007 Fuel is any material that stores energy that can later be extracted to perform mechanical ... a combustible substance releases energy after it ignites and reacts with the oxygen in the air. Other processes used to convert fuel into energy include various other exothermic reaction exothermic ... of fuel used by humans, but many other substances, such as radioactive metals, are currently used ... defined as solid, liquid, or gas fuel consisting of, or derived from biomass . Biomass can also be used directly for heating or power known as biomass fuel . Biofuel can be produced from any carbon source ... are used for biofuel manufacture. Perhaps the earliest fuel employed by humans is wood. Evidence shows ... 2007 09 11 ref As a fuel, wood has remained in use up until the present day, although it has been ... fuels Main Fossil fuel Fossil fuels are hydrocarbon s, primarily coal and petroleum liquid ... ref Cite web author Dr. Irene Novaczek title Canada s Fossil Fuel Dependency url http www.elements.nb.ca ... of years. ref Cite web title Fossil fuel url http oaspub.epa.gov trs trs proc qry.navigate term ... retrieved archive archivedate 12 March 2007 ref Commonly, the term fossil fuel also includes hydrocarbon ... sands . These latter sources are properly known as mineral fuels . Nuclear Main Nuclear fuel Nuclear fuel is any material that is consumed to derive Nuclear power nuclear energy . Technically speaking ... that will produce energy without being placed under extreme duress. Fission Image Nuclear fuel pellets.jpeg thumb right Nuclear fuel pellets are used to create nuclear energy. The most common type of nuclear fuel used by humans is heavy fissile elements that can be made to undergo nuclear fission chain reaction s in a nuclear reactor nuclear fission reactor nuclear fuel can refer to the material or to physical objects for example fuel bundles composed of fuel rod s composed of the fuel material ... make up the nuclear fuel cycle , which is important for its relevance to nuclear power generation ... more details
The A S ratio is the proportion of the brain not directly connected with either receptor inputs or motor outputs, where A is the association cortex and S is the sensory cortex . The A S ratio can be measured for any organism with a brain, and the higher the A S ratio, the more complex the brain is. It was proposed by Donald Olding Hebb Donald Hebb in 1949. References cite book last Lerner first Dr. Richard M. title Concepts and Theories of Human Development year 2002 publisher L. Erlbaum location Mahwah, N.J. isbn 0585387362 9780585387369 oclc 49569701 DEFAULTSORT A S Ratio Category Central nervous system Category Cerebrum Category Neuroanatomy neuroanatomy stub ... more details
Otheruses4 the mathematical concept the Swedish institute Ratio Institute the academic journal Ratio journal the philosophical concept Reason the legal concept Ratio decidendi File Aspect ratio 4x3.svg thumb The ratio of width to height of standard definition television . In mathematics , a ratio is a relationship ... an integer . ref Penny Cyclopedia, p. 307 ref In layman s terms a ratio represents, simply, for every ... of socks for every pair of shoes then the ratio of shoes socks would be 1 10 and the ratio of socks shoes would be 10 1 Notation and terminology The ratio of numbers A and B can be expressed as ref New International Encyclopedia ref the ratio of A to B A is to B A B A rational number which is the quotient ... wiktionary It is impossible to trace the origin of the concept of ratio, since the ideas from which .... ref Smith, p. 477 ref However, it is possible to trace the origin of the word ratio to the Ancient Greek logos . Early translators rendered this into Latin as wikt ratio Latin ratio reason ..., p. 307 ref Medieval writers used the word proportio proportion to indicate ratio and proportionalitas ... of ratio and proportion as applied to numbers. ref Heath, p. 112 ref The Pythagoreans conception ... what a ratio is in a general way. It is not rigorous in a mathematical sense and some have ascribed ... Eleventh Edition p682. ref Euclid defines a ratio to be between two quantities of the same type , so by this definition the ratios of two lengths or of two areas are defined, but not the ratio of a length and an area. Definition 4 makes this more rigorous. It states that a ratio of two quantities exists when there is a multiple of each which exceeds the other. In modern notation, a ratio exists ... not be possible to assign a rational value to a ratio, it is possible to compare a ratio with a rational number. Specifically, given two quantities, p and q , and a rational number m n we can say that the ratio ... that have the same ratio are proportional or in proportion . Euclid uses the Greek analogon ... more details
Unreferenced date January 2011 Smokeless fuel means fuel which does not produce visible smoke when burned. The term is usually applied to solid fuel s, such as Anthracite Coke fuel Coke Charcoal Hexamine fuel tablet s See also Clean Air Act 1993 Clean Air Act 1956 Category Fuels Tech stub ... more details
the relationship of range with airspeed , lift to drag ratio , specific fuel consumption , and the part of the total fuel fraction available for cruise, also known as the cruise fuel fraction , or cruise fuel weight fraction . ref cite book title Flight Performance of Fixed and Rotary Wing Aircraft ...About flight vehicles the topic in combustion physics fuel mass fraction File GlobalFlyer at KSC before launch.jpg thumb The Virgin Atlantic GlobalFlyer GlobalFlyer had a fuel fraction near 85 it could carry five times its weight in fuel. In aerospace engineering , an aircraft s fuel fraction , fuel ... ref or a spacecraft s propellant fraction , is the weight of the fuel or propellant divided ... s, the term internal fuel fraction is used to exclude the weight of external tanks and fuel. Fuel ... At today s state of the art for jet fighter aircraft , fuel fractions of 29 percent and below ... for useful supercruising missions. The U.S. F 22 Raptor s fuel fraction is 29 percent ref http ... . The Russian supersonic interceptor, the Mikoyan MiG 31 Foxhound , has a fuel fraction of over ... E. Riccioni, Col. USAF, Ret. ref The Panavia Tornado had a relatively low internal fuel fraction ... ref Airliners Airliners typically have a fuel fraction between 25 to 45 percent, so less than half their takeoff weight is fuel. The Boeing 777 200 IGW very long range airliner has a fuel fraction ... Analysis by Dr. Martin Hepperle ref The Concorde supersonic transport had a high fuel fraction ... Noland, David month February year 2005 url http www.popularmechanics.com science air space 1262012.html?page 3 ref Steve Fossett s Virgin Atlantic GlobalFlyer could attain a fuel fraction of nearly 85 percent, meaning that it carried more than five times its empty weight in fuel. ref cite news first ... 03 18 quote At takeoff, fuel is expected to account for almost 85 percent of the graphite made aircraft s weight. ref See also Mass ratio References reflist Category Aerospace engineering ... more details
fuelairratio than is ideal to keep the engine cool as the fuel going out the exhaust also takes heat ...unreferenced date December 2006 Glow fuel is a generic term used to describe a fuel source used in model ... . Glow fuel can be burned by very simple two stroke engines or by more complicated four stroke engines and these engines can provide impressive amounts of power for their very small size. Glow fuel is primarily for two stroke engines with the need for oil mixed in the fuel and limited exhaust and fuelair between cycles. Top Fuel race cars with 4 cycle engines also use methanol nitromethane mixtures but do not contain appreciable oil. Name Other commonly used names are nitro or just model fuel ... Internationale , which requires such fuel in some forms of aeromodeling competition, contain no nitromethane at all. Ingredients Glow fuel is a mixture of methanol , nitromethane , and oil . Methanol is the primary ingredient as it provides the bulk of the fuel, and is needed as a solvent ... the engine easier to tune. Typically glow fuel is about 0 30 nitromethane. While higher concentrations ... stroke, which allows the engine to draw in more fuel while still maintaining a favorable mixture setting. The increased amount of fuel entering the engine increases power output, and also aids in cooling ... is often difficult to obtain in many countries, so in these countries glow fuel typically has no nitromethane at all. Lubrication Most model engines require oil to be included with the fuel as a lubricant since the engine has no independent oiling capability. Model engine fuel is typically 8 22 ... glow fuels include a mixture of the two. The oils included in glow fuel generally are not burned by the engine ... and poppet valves of larger sized four stroke engines, are generally meant to use glow ignition and their fuel. Often, the oil percentage for four stroke glow fuel can be lowered from the 18 20 figure used for some two stroke engines, down to as low as a 12 15 percentage per unit of blended glow fuel ... more details
the head or combustion chamber has been reduced to 100 cc, then the compression ratio would be proportionally described as 1000 100, or with fractional reduction, a 10 1 compression ratio. A high compression ratio is desirable because it allows an engine to extract more mechanical energy from a given mass of airfuel mixture due to its higher thermal efficiency . Citation needed reason this is not because ... supercharger already having compressed the fuelair mixture considerably before it enters ... heat ratio for the working fluid, which is about 1.4 for air, and 1.3 for methane air mixture ... ratio. This exponent is a polytropic value for the ratio of variable heats for air and similar gases ... near operating temperature . A running engine does not stop taking air & fuel into the cylinder ... is the ratio of specific heats for air approximately 1.4 . The values in the table above are derived ...For compression ratio in data compression data compression ratio Refimprove date May 2009 The compression ratio of an internal combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity. It is a fundamental specification for many common combustion engines. In a piston engine it is the ratio ... Compression ratio url http www.britannica.com EBchecked topic 130313 compression ratio accessdate 2009 ... containing 1000 cc of air 900 cc in the cylinder plus 100 cc in the combustion chamber . When ... of the compression. date April 2011 High ratios place the available oxygen and fuel molecules ... of the fuel droplets. Citation needed reason you should not say adiabatic heat of compression ... make gasoline engines subject to engine knocking if lower octane rated fuel is used, also ... of compression ignition, so that a fuel which resists autoignition will cause late ignition which will also lead to engine knock. Formula The ratio is calculated by the following formula math mbox ... more details
mergefrom Fuel price risk management date March 2011 Fuel Hedging is a contractual tool some large fuel ... fuel costs. A fuel Hedge finance hedge contract allows a large fuel consuming company to establish a fixed or capped cost, via a commodity swap or option. Large fuel consuming companies enter into hedging contracts to mitigate their exposure to future fuel prices that may be higher than current prices and or to establish a known fuel cost for budgeting purposes. If a large fuel consuming company buys a fuel swap and the price of fuel declines, the company will effectively be forced to pay an above market rate for fuel. If a large fuel consuming company buys a fuel call option and the price of fuel increases, the company will receive a return on the option that offsets their actual cost of fuel. If a large fuel consuming company buys a fuel call option, which requires an upfront premium cost, much like insurance, and the price of fuel decreases, the company will not receive a return on the option but they will benefit from buying fuel at the then lower cost. Background The cost of fuel hedging depends on the predicted future price of fuel. Airlines may place hedges either based on future prices of jet fuel or on future prices of crude oil . ref Some Airlines Turning To Fuel Hedging ... fuel, the prices of crude oil and jet fuel are normally correlated. However, other factors, such as difficulties ... of crude oil and jet fuel. A company that does not hedge its fuel costs generally believes one, if not both, of the following 1. The company has the ability to pass on any and all increases in fuel ... that fuel prices are going to fall and is comfortable paying a higher price for fuel if, in fact, their analysis proves to be incorrect. ref HEDGING ALLOWS COMPANIES TO LOCK IN FUEL PRICES AND MARGINS ... a certain portion of their fuel requirements for a certain period. Often, contracts for portions of an airline s jet fuel needs will overlap, with different levels of hedging expiring over time. During ... more details
F 111 fuel dump and burn Williamtown Gilbert.jpg right thumb Royal Australian Air Force RAAF F 111 ... Air New Zealand Flight 103 use of fuel dumping in an attempt to make the aircraft more visible References ...Refimprove date January 2008 File FuelDumpA340 600.JPG thumb Fuel dumping of an Airbus A340 Airbus A340 600 above the Atlantic Ocean near Nova Scotia File FDP A340.JPG right thumb Fuel dump nozzle of an Airbus A340 Airbus A340 300 Fuel dumping or a fuel jettison is a procedure used by aircraft in certain ... s weight or to reduce risk of fire. Aircraft fuel dump Aircraft have two major types of weight limits ... on a normal, routine flight to take off at the higher weight, consume fuel en route, and arrive at a lower ... medical issue , there will not be time to consume the fuel meant for getting to the original ... Aviation Administration FAA rule in effect at the time mandated that if the ratio between an aircraft ... than 105 , the aircraft had to have a fuel dump system installed. Accordingly, aircraft such as the Boeing 707 and Boeing 727 727 and the Douglas DC 8 had fuel dump systems. Any of those aircraft needing ... an amount of fuel sufficient to reduce the aircraft s total weight to below that maximum structural ... for shorter routes the 105 figure was not an issue, thus they had no fuel dump systems installed. During ... rule became problematic due to the costs associated with adding a fuel dump system to aircraft in production ... A320 family and various regional jet Regional jet RJ aircraft do not have fuel dump systems installed ... nearby in order to consume fuel to get down to within the maximum structural landing weight limit, or if the situation ... mistakenly assume that all aircraft can dump fuel, when in fact most cannot. In certain atmospheric conditions where the moisture content of the air is high, Boeing 737 737s and other aircraft ... trails and wrongly think fuel is being dumped. Longer range twin jets such as the Boeing 767 and the Airbus A300 , Airbus A310 A310 , and Airbus A330 A330 may or may not have fuel dump systems ... more details
March 2010 class wikitable Fuel Energy density Energy br Energy density density airfuelratioAirfuel br airfuelratioratio Specific energy Specific br Specific energy energy Heat of vaporization ... at richer mixtures than gasoline. Standard gasoline engines in cars can adjust the airfuelratio ... for retrofit as the airfuelratio and energy content are closer to that of gasoline. ref name colostate ... specific energy is sometimes used. It is defined as the energy released per airfuelratio ... fuelairratio of butanol, ethanol and gasoline. Common ethanol fuel mixtures for fuel sold as gasoline ... colwidth 30em Agricultural byproduct Airfuelratio Bioalcohol Biofuel Biodiesel Biohydrogen Bioconversion ... 32 MJ L 14.6 2.9 MJ kg air 0.36 MJ kg 91 99 81 89 Butanol fuel 29.2 MJ L 11.1 3.2 MJ kg air 0.43 MJ kg 96 78 Ethanol fuel 19.6 MJ L 9.0 3.0 MJ kg air 0.92 MJ kg 107 89 Methanol fuel 16 MJ L 6.4 3.1 MJ kg air 1.2 MJ kg 106 92 ref Internal Combustion Engines ... the compression ratio, further gains in fuel economy, power and torque can be achieved ... DICTIONARY OF AUTOMOTIVE TERMS En scroll way down to engine knock accessdate 2008 03 21 ref Airfuel ...About Butanol from biomass used as a fuel other alcohols used as fuels Alcohol fuel Butanol may be used as a fuel in an internal combustion engine . Because its longer hydrocarbon chain causes it to be fairly ... as fossil fuel s as petrobutanol but biobutanol and petrobutanol have the same chemical properties ... , and announced in the late summer of 2011 the university s alternative fuel research scientists ..., 2012 ref Algae butanol Main Algae fuel Diatom Biobutanol can be made entirely with solar energy, from algae called Solalgal Fuel or diatom s. ref http www.fossilfreedom.com Fossil Freedom Home Page ... pipeline s for gasoline. ref name dupont In blends with Diesel fuel diesel or gasoline, butanol is less likely to separate from this fuel than ethanol if the fuel is contaminated with water. ref name ... more details
In chemistry and physics , the dimensionless mixing ratio is defined as the abundance of one component of a mixture relative to that of all other components. The term can refer either to mole ratio or mass ratio. ref GoldBookRef file M03948 title mixing ratio ref Mole ratio In atmospheric chemistry , mixing ratio usually refers to the mole ratio math r i math , which is defined as the amount of substance amount of a constituent math n i math divided by the total amount of all other constituents in a mixture math r i frac n i n tot n i math The mole ratio is also called amount ratio . ref http www.iupac.org publications pac 80 2 0233 ref If math n i math is much smaller than math n tot math which is the case for atmospheric trace constituents , the mole ratio is almost identical to the mole fraction . Mass ratio In meteorology , mixing ratio usually refers to the mass ratio math zeta i math , which is defined as the mass of a constituent math m i math divided by the total mass of all other constituents in a mixture math zeta i frac m i m tot m i math The mass ratio of water vapor in air can be used to describe Humidity Mixing ratio or humidity ratio humidity . References Reflist Category Units of chemical measurement fa fr Rapport de m lange it Rapporto di mescolanza ... more details
cylinders may be signalled to open at the same time in a batch fire system . Target airfuel ratios The relative proportions of air and fuel vary according to the type of fuel used and the performance requirements ie power, fuel economy or exhaust emissions . See airfuelratio , stoichiometry ... compressed air cn date April 2012 . Fuel injection was in widespread commercial use in diesel engine ..., using engine speed and intake manifold air density to calculate air mass flow rate and thus fuel ... control fuelair mixtures, in order to further reduce exhaust emissions. Later Control theory Closed loop transfer function Closed loop fuel injection systems improved the airfuel mixture control ... air the location of the fuel injector varies between systems . date April 2012 EFI gasoline ... such as the air cleaner, intake manifold, and fuel line routing could be reused. This postponed ... valve for the air, which is linked by a mechanical linkage to a rotary valve for the fuel. Inside ... chamber as opposed to fuel and air mixing before the intake valve . ref cite web url http www.unep.org ... injected fuel, the cylinder and piston are cooled, thereby permitting higher compression ratio ... of the fuel mixture allows for leaner airfuel ratios, which together with more precise ... fuel injector is removed from its seat and operated in open air, there is a risk to the operator ... yes File Jeep 2.5 liter 4 cylinder engine chromed i.jpg thumb 300px Fuel rail connected to the injectors that are mounted just above the intake manifold on a four cylinder engine. Fuel injection is a system for admitting fuel into an internal combustion engine . It has become the primary fuel delivery ... engine. The primary difference between carburetors and fuel injection is that fuel injection atomizer nozzle atomizes the fuel by forcibly pumping it through a small nozzle under high pressure, while a carburetor relies on suction created by intake air rushing through a Venturi tube Venturi tubes ... more details
management ref Cite web url http www.ika.rwth aachen.de r2h index.php Water and Air Management for Fuel ... buffer Good Sort 39 40 Beta Research Rh Magnesium AirFuel Cell salt water Good Sort 20 20 55 Good Sort ...Other uses Image Fuel cell NASA p48600ac.jpg thumb 250px right Demonstration model of a direct methanol fuel cell. The actual fuel cell stack is the layered cube shape in the center of the image A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical ... Science url http www.biblio.com books 436308472.html ref Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from battery electricity batteries in that they require a constant source of fuel and oxygen to run ... William Robert Grove William Grove developed the first crude fuel cells in 1839. The first commercial use of fuel cells was in NASA space programs to generate power for probes, satellites and space capsules. Since then, fuel cells have been used in many other applications. Fuel cells are used for primary ... areas. They are used to power fuel cell vehicle s, including automobiles, buses, forklifts, airplanes, boats, motorcycles and submarines. There are many types of fuel cells, but they all consist ... between the two sides of the fuel cell. Electrons are drawn from the anode to the cathode through an external circuit, producing direct current electricity. As the main difference among fuel cell types is the electrolyte, fuel cells are classified by the type of electrolyte they use. Fuel cells come in a variety of sizes. Individual fuel cells produce very small amounts of electricity, about 0.7 ...,Jonathan. http auto.howstuffworks.com fuel efficiency alternative fuels fuel cell2.htm How Fuel Cells Work Polymer Exchange Membrane Fuel Cells . How Stuff Works, accessed August 4, 2011 ref In addition to electricity, fuel cells produce water, heat and, depending on the fuel source, very small ... more details
of transport , fuel economy is the energy efficiency of a particular vehicle, and is given as a ratio of distance travelled per unit of Motor fuelfuel consumed. Fuel economy is expressed in mile ... ratio, fuel consumption , is usually expressed in liter s per 100 kilometers L 100 km .... The higher compression ratio is helpful in raising the energy efficiency, but diesel fuel also contains ...Fuel efficiency is a form of thermal efficiency , meaning the efficiency of a process that converts chemical potential energy contained in a carrier fuel into kinetic energy or Mechanical work work . Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum ..., such as industry , benefit from increased fuel efficiency, especially fossil fuel power plant s or industries ... . Variations on a vehicle s fuel efficiency include weight specific efficiency for freight , and passenger specific efficiency vehicle efficiency number of passengers . Vehicle design Fuel efficiency ... to heat during braking is recaptured as electrical power to improve fuel efficiency. Fleet efficiency ... is similar to fuel efficiency but the input is usually in units of energy such as British thermal ... is measured by the amount of fuel and the output is measured by the distance travelled. For example Fuel economy in automobiles . Given a heat value of a fuel, it would be trivial to convert from fuel ... containing fuel which can differ by several percent see below . When comparing transportation energy costs, it must be remembered that a kilowatt hour of electric energy may require an amount of fuel with heating value of 2 or 3 kilowatt hours to produce it. Energy content of fuel The specific energy content of a fuel is the heat energy obtained when a certain quantity is burned such as a gallon ... of specific heat energy for the same batch of fuel. One is the high or gross heat of combustion and the other ... align left Fuel type align right MJ L align right MJ kg align right British thermal unit BTU gallon ... more details
Unreferenced date November 2009 Oxy fuel refers to technology that combustion burns oxygen with gaseous fuel . As compared to air , which contains 20.95 oxygen, higher temperatures can be reached using pure oxygen. Approximately the same total energy is produced when burning a fuel with oxygen as compared to with air the difference is the lack of temperature diluting inert gases. The most common fuel burned in a torch with oxygen is acetylene even though it presents special handling problems, it has the greatest heat output. The process has also been proposed as a method of capturing carbon dioxide from coal fired electric power plants because the output flue gases from combustion in oxygen as opposed to air have a higher carbon dioxide content fraction. See Oxy fuel combustion process . See also Oxy fuel combustion process Oxy fuel welding and cutting High velocity oxy fuel coating Oxyhydrogen Category Fuels tech stub fr Oxycombustion nl Oxyfuel ja ... more details
1 bypass ratio, for every 1 kg of air passing through the combustion chamber, 10 kg of air passes around the combustion chamber through the ducted fan alone. In a high bypass design ..., pp 322 333 ref A high bypass ratio provides a lower thrust specific fuel consumption grams sec fuel ... turbofan used in the F 4 Phantom . Principles In a gas turbine engine, the stoichiometry of the fuelair mixture is limited to a fairly narrow range, with a tendency to a leaner fuel mixture to limit ... turbofan engines the high bypass engine middle has a large fan that routes much air around the turbine, the low bypass engine upper has a smaller fan routing more air into the turbine turbojets bottom have zero bypass, all air goes through the turbine br The bypass air is shown in pink, whilst the core gases are shown in red. The term bypass ratio BPR relates to the design of turbofan engines, commonly used in aviation . It is defined as the ratio between the mass flow rate of air drawn through a fan disk which bypasses the engine core un combusted air , to the mass flow rate passing ... for military combat aircraft as a compromise between improved fuel economy and the requirements of combat, which values higher power to weight ratio s, supersonic performance, and the ability ... a propelling nozzle the lesser part of the thrust is obtained by accelerating air in the compressor stage . Note that in a zero bypass engine all the air taken in is involved in combustion. In a pure .... This excess power is used to drive a ducted fan to accelerate air from the front of the engine rearwards ..., one passing through the core combustion air and air passing through the ducted fan alone since in reality, most designs pass combustion air through the ducted fan first before passing into the compressor ... ratio of the system, by adding to the compressor stage, can increase overall system efficiency at the cost ... of air through a relatively small change in velocity. The physics of propulsive efficiency may ... more details
mounted fuel pump is that a suction pump at the engine could suck in air through a difficult to diagnose ...distinguish fuel dispenser Unreferenced date October 2006 Image High pressure fuel pump.JPG thumb A high pressure fuel pump on a Yanmar 2GM20 marine diesel engine . A fuel pump is a frequently but not always ... older motorcycle engines in particular do not require any fuel pump at all, requiring only gravity to feed fuel from the fuel tank through a line or hose to the engine. But in non gravity feed designs, fuel has to be pumped from the fuel tank to the engine and delivered under low pressure to the carburetor or under high pressure to the fuel injection system. Often, carbureted engines use low pressure mechanical pumps that are mounted outside the fuel tank, whereas fuel injected engines often use electric fuel pumps that are mounted inside the fuel tank and some fuel injected engines have two fuel pumps one low pressure high volume supply pump in the tank and one high pressure low volume pump on or near the engine . Mechanical pump Image fuelpump1.jpg thumb right Mechanical fuel pump, fitted to cylinder head Prior to the widespread adoption of fuel injection electronic fuel injection , most carbureted automobile engines used mechanical fuel pumps to transfer fuel from the fuel tank into the fuel bowls of the carburetor. Most mechanical fuel pumps are diaphragm pumps, which are a type ... to force the fuel to flow in one direction only. Specific designs vary, but in the most common ... the pump chamber increased, causing pressure to decrease.This allows fuel to be pushed into the pump from the tank caused by atmospheric pressure acting on the fuel in the tank . The return motion of the diaphragm to top dead center is accomplished by a diaphragm spring, during which the fuel in the pump chamber is squeezed through the outlet port and into the carburetor. The pressure at which the fuel ... spring. The carburetor typically contains a float bowl into which the expelled fuel is pumped ... more details
airfuel mixture. Like the original Hemi, the racing cylinder block has a long skirt to reduce ... airfuel mixture for their cooling. The original Chrysler design of two large valves ..., from the volatile airfuel mixture coming from the fuel injector s being drawn directly through them ... that nearly any irregularity in the induction of the airfuel mixture, the conversion of combustion ... speed builds, the airfuel mixture is enriched. As the increased engine speed builds up pump ... the tires and the race is often lost. Ignition and timing The airfuel mixture is ignited by two ... Russell , the fuelratio was reduced to 85 . Complaints from teams in regards to cost, however, has ... Race Track in Kwinana, Western Australia, 2005 Image Top Fuel dragster time, Indianapolis, 2004.jpg thumb right Top fuel dragster time 4.567 s at convert 321 mi h km h abbr on Top Fuel racing is a class ... vehicles. However, top fuel dragsters are much longer, much narrower, and are equipped with large tires ... and speed. Top fuel dragsters are the fastest category of drag racers, with the fastest competitors .... A top fuel dragster accelerates from a standstill to 160 km h 100 mi h in as little as 0.7 seconds ... force of about G forces 4.0 G over the duration of the race. Facts about Top Fuel File 2009NHRATopFuelChampTrophyTonySchumacher.jpg thumb upright left 2009 NHRA Top Fuel championship trophy ... kN when the car reaches a speed of about convert 324 mi h km h abbr on . The engine of a Top Fuel ... the experience of watching a Top Fuel dragster make a pass to feeling as though the entire drag ... their ears. Ear plugs and even earmuffs are often handed out to fans at the entrance of a Top Fuel event. Dragsters are limited to a maximum length of 300 inches. The fuel NHRA regulations limit the composition of the fuel to a maximum of 90 nitromethane Since 2008 the remainder is largely methanol ... than an engine burning gasoline. This is made possible by the fact that, in addition to fuel, an engine ... more details
the air inside the cylinder to high pressures and temperatures compression ratio s from 14 1 ... ref , burning the fuel in more air than is required for the chemical reaction. They thus use less fuel than rich burn spark ignition engines which use a Stoichiometry Stoichiometric airfuelratio just enough air to react with the fuel . Because they have high compression ratios and no throttle ... also provide fuel for a runaway, via the engine air intake. ref http www.tb training.co.uk CIsys.htm ... oil for diesel engine s. Diesel fuel IPAc en icon d i z l in general is any liquid fuel used ... fuel oil , but alternatives that are not derived from petroleum, such as biodiesel , biomass ... doi abs 10.1021 ef0502711 article on comparing Petrodiesel emissions with other types of fuel ... itself. ref Ultra low sulfur diesel ULSD is a standard for defining diesel fuel with substantially lowered sulfur contents. As of 2007, almost all diesel fuel available in the United States of America, Canada and Europe is the ULSD type. In the UK, diesel fuel for on road use is commonly abbreviated DERV , standing for Diesel Engined Road Vehicle , which carries a tax premium over equivalent fuel ... coal dust as a fuel. He also experimented with various oils, including some vegetable oils, ref ... Fuel Alternative for Diesel Engines publisher Springer location Berlin year 2008 pages 74 isbn 1 84628 ... Diesel fuel is produced from petroleum and from various other sources. Petroleum diesel File essodiesel.jpg ... 99 108. Humana Press. ISBN 1588295419. ref Fuel value and price See Gasoline and diesel usage and pricing ... kg l 6.217 lb US gal . About 86.1 of the fuel mass is carbon, and when burned, it offers ... when comparing the fuel efficiency by volume. The CO sub 2 sub emissions from diesel are 73.25 g ... in much the same way. Because of recent changes in fuel quality regulations, additional refining ... Fuel Update Bot generated title ref Reasons for higher priced diesel include the shutdown of some ... more details
Orphan date October 2008 Image Low clouds.jpg thumb 150px A moisture ratio compares an amount of air to an amount of moisture. A moisture ratio is a ratio that compares the mass or volume of air to the mass or volume of moisture contained in that air. In construction , it is an important consideration when design ing a building for a certain climate . Nall as cited in References called it one of the most important climate variables for human comfort and building energy efficiency . References Nall, D. H. 2004 11 . Looking across the water Climate adaptive buildings in the United States & Europe. In The Construction Specifier, 57 , 50 56. Category Ratios climate stub ... more details
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