Epas program to study the efficiency potential of future gasoline engines us environmental protection agency 7. This is an old term for a piece of hardware now more commonly called a dyno. Or, to put this another way, what causes an increase in fuel used per kw at both low and high revs. It is thus thrustspecific, meaning that the fuel consumption is divided by the thrust. Brake specific fuel consumption is one of those measurements.
Brake specific fuel consumption take me beyond the horizon. The aim is to optimize engine power and brake specific fuel consumption bsfc where the effect of engine speed has also been considered. Bsfc brake specific fuel consumption which units are btu bhph. Natural gas compressor engine survey for gas production and. Because differences in the fuel consumption of vehicles relate directly to fuel savings, the labeling on new cars and lightduty trucks should include information on the gallons of fuel consumed per 100 miles traveled in addition to the alreadysupplied data on fuel economy so that consumers can become familiar with fuel. How can i calculate the best brake specific fuel consumption. From the graph the maximum volumetric efficiency is 69. Combustion efficiency is maximized when bsfc is minimum. Epas program to study the efficiency potential of future gasoline engines us environmental protection agency 11. Engine brake specific fuel consumption bsfc wheel wheel brake specific fuel consumption cd chassis dynamometer. Development of variable temperature brake specific fuel consumption engine maps 2010012181 response surface methodology rsm techniques are applied to develop brake specific fuel consumption bsfc maps of a test vehicle over standard drive cycles under various ambient conditions. I ran across an sae white paper written by toyota about the development of this engine, and it included a bsfc.
How do you adjust the spark and fuel to obtain minimum bsfc without an attending loss in power. The air density is fixed by the environment and the afr is fixed by the type of fuel used, so the only variable left is bmep d. Many western states in the western regional air program. Also find brake specific fuel consumption in gkwh and thermal brake efficiency. Brake specific fuel consumption open source ecology. It is the rate of fuel consumption divided by the power produced. Brake specific fuel consumption an overview sciencedirect. Here ill expain a bit more on the bsfc and how it affects our cars.
Brake specific fuel consumption or bsfc is the ratio between the engines fuel mass consumption and the crankshaft power it is producing. How to adjust for minimum brake specific fuel consumption. Engine testbed, fuel gauge, air flow meter, speedometer, brake power, specific fuel consumption and engine performance speed. View brake specific fuel consumption research papers on academia. Assessing the efficiency potential of future gasoline. I have a 1992 evinrude v6 loopscavenged 225hp twostroke which is in good tune and for which i have some fuel consumption data. Useful for determining at what load and rpm your engine is making the most power out of the fuel given to it. The thermal efficiency is about 31%, corresponding to 260 grams of gas per kilowatthour of brake flywheel power output 1 gram of gasoline contains about 44,000 joules of energy. Is there a graph for the ls1 engine showing bmep brake mean effective pressure against engine speed.
Various performance characteristics such as bte, brake specific fuel consumption bsfc, and brake specific energy consumption are used to study the properties of biodiesel under various conditions. Im trying to modify my driving style to achieve the best fuel economy. Brake specific fuel consumption bsfc is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft, power. Heavyduty vehicle diesel engine efficiency evaluation and. Brake specific fuel consumption question bob is the oil guy. As ankur said, you do not calculate the consumption, it is given by manufacturer. The higher the compression ratio the more efficient the engine. View brake specific fuel consumption bsfc xengineerorg.
Problems on internal combustion engines engine fundamentals 1. Thrust specific fuel consumption tsfc is the fuel efficiency of an engine design with respect to thrust output. Engine power p and brakespecific fuel consumption fc at full load of the same engine running with market diesel do and biodiesel b5 b5 are given in fig. This means operation of an engine at its normal maximum cylinder pressure for the design continuous service rating, but at lower mean effective pressure and shaft speed. Brake specific fuel consumption, abbreviated bsfc and also known by the term power specific fuel consumption or simply specific fuel consumption, is a type of comparison ratio which looks at an engines fuel efficiency in terms of how much fuel the car uses versus how much power it produces. Mar 09, 2014 brake specific fuel consumption is the ratio of fuel consumption in kghr to the brake powerkw. Such engines are often charged with more than 50% of full. Specific attention is paid to the changes in brake specific fuel consumption bsfc and changes in brake specific emissions. Brake specific fuel consumption bsfc \u20 xengineerorg. Brakespecific fuel consumption bsfc is a measure of the fuel efficiency of any prime. Its usually stated in mass units grams per kwh gkwh or pounds per brake horsepower hour lbbhphr but ive occasionally seen it quoted in liters per. It is indicative of how much fuel is consumed in producing 3. The formula for calculating brake specific fuel consumption is fuel consumption divided by power, and. The lower the brake specific fuel consumption, the more efficient the engine is.
The use of bio fuel as an alternative fuel in diesel. With reciprocating engines, most values available for brake mean effective pressure do not represent the bmep differential as defined previously. Measuring various attributes of an ice internal combustion engine and how it performs certainly gives a greater understanding of how a particular ice performs at various rpms as well as give the ability to understand economy. Pdf fast extremum seeking for optimization of brake. Brakespecific fuel consumption jim explains how bsfc. Epa this document summarizes the process followed to utilize the fuel consumption map of a ricardo. Nov 03, 2014 brake specific fuel consumption bsfc is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft, power. It is used to evaluate how well an engine converts the heat from a fuel to mechanical energy. Pdf effect of engine backpressure on the performance and. These calculations are popular because the mechanic can compare any number of engines, regardless of size, to see which is the most efficient. Brake specific fuel consumption research papers academia. Process for generating engine fuel consumption map ricardo cooled egr boost version. The estimate of brake specific fuel consumption for twostroke engines ranges from 0.
At this condition, also, the brake specific fuel consumption bsfc is increased by 3. Natural gas compressor engine survey for gas production. Modeling the effect of variable timing of the exhaust. Brake specific fuel consumption bsfc is a measure of the efficiency of an internal combustion engine. Whether youre an engine builder or engaged in testing them on an engine dynamometer, a clear and working understanding of brakespecific fuel consumption bsfc can be of value. It may also be thought of as power specific fuel consumption, for this reason.
This makes it both a valuable fuel efficiency indicator and one more useful tool in gauging an engines stateoftune. Brakespecific fuel consumption article about brake. Emission factors in lbhphr were calculated using emission factors in lbmmbtu and a brake specific fuel consumption of 7000 btuhphr ap 42 table 3. Thrustspecific fuel consumption tsfc is the fuel efficiency of an engine design with respect to thrust output. The fuel consumption reduction for the 2017 engine was factored to achieve at a minimum the 2017 co. Interesting graphs about brake specific fuel consumption. The term specific fuel consumption refers to the amount of fuel used normalized to the amount of power generated, which gives you an efficiency at at certain operating point of the engine. Doug woodyard, in pounders marine diesel engines and gas turbines ninth edition, 2009. The brake specific fuel consumption of an engine is usually represented as a contour plot, function of engine speed and torque or mean.
The measured fuel consumption is 160 kg of fuel in one hour and air consumption is 410 kg during one sixth of an hour. An option available to reduce the specific fuel consumption of diesel engines is derated or socalled economy ratings. The graph shows that the thermal efficiency is almost same at engine speed 1400 rpm to 1500 rpm, and then it is increasing until engine speed 2000 rpm. However, if i could drive at a steady speed of 35 mph using only 8 hp 6000 watts at 1500 rpm 5th gear, the thermal efficiency is probably closer to 24%. Specific fuel consumption an overview sciencedirect topics. The least amount of brake specific fuel consumption at minimum speed and load torque peak is observed. I will go into the bsfc in another post part 3b in more detail. It is typically used for comparing the efficiency of internal combustion engines with a shaft output. Fast extremum seeking for optimization of brake specific fuel consumption conference paper pdf available december 2014 with 101 reads how we measure reads. Brake specific fuel consumption bsfc measure of fuel efficiency within a shaft reciprocating engine. Plan for 3035% more fuel consumption than gasoline burning engines. The condition of the fuel injectors since ones making a good controlled spray will be better. Fuel consumption in gas engines industrial professionals. Development of variable temperature brake specific fuel.
The difference is that they are found using the theoretical volumetric flow rate q th instead of the measured volumetric flow rate q m, i. It is typically used for comparing the efficiency of internal combustion engines with a shaft output it is the rate of fuel consumption divided by the power produced. I recently acquired a 2007 toyota corolla le with the 1zzfe engine and a 5speed transmission. Internal combustion engine performance characteristics. The axes are horizontally rotational speed, n, in rpm and vertically mean effective pressure p e bar. Fuel properties were determined to correct brake specific fuel consumption bsfc and emissions to standard fuel data. The broader category includes parts designers and those interested in evaluating power level changes involving parts or modifications. Brake specific fuel consumption renegade race fuel. Fuel consumption analysis of a sample of diesel engine. Brake specific fuel consumption bsfc maps ecomodder. Tsfc may also be thought of as fuel consumption gramssecond per unit of thrust kilonewtons, or kn.
Brake specific fuel consumption bsfc is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft power. The baseline brake specific co 2 emissions is an approximation based on the mass of fuel consumed and not a result of emissions measurement. Sep 01, 2011 whether youre an engine builder or engaged in testing them on an engine dynamometer, a clear and working understanding of brake specific fuel consumption bsfc can be of value. This specific compressor works with 40 mmscfd from 450 to 915 psig. Dec 31, 20 first it is called brake because it is measured on the brake. Brake specific fuel consumption bsfc is a parameter that reflects the efficiency of a combustion engine which burns fuel and produces rotational power at the shaft or crankshaft. Brake specific fuel consumption for compressor engines engine type representative model size hp fuel consumption mmbtuhphrhhv 4 stroke, rich, brake specific energy consumption is increased by 0. Brake specific fuel consumption moderated discussion areas. Brake specific fuel consumption gkwhr sae international topics 1.
Finally the universal bsfc map contour is the best way to understand the whole and the best fuel consumption of an engine. The brake mean effective pressure bmep is the equivalent average pressure acting on the piston during the entire volume change in the cylinder. May 10, 2016 there are several factors that come to mind. Is this the same or similar process to the auto ve process. In the example provided below, calculations are provided for emergency and nonemergency 525 hp digester gas or methane fired engines. This diagram shows the brake specific fuel consumption bsfc gkwh of the smart forfour 3cylinder diesel engine with 1. What factors affect the brake specific fuel consumption of a. The last section compares processed summary data including cycletocycle variation, brake specific fuel consumption and brake specific emissions for the same selected operating points. The formula for calculating brake specific fuel consumption is fuel consumption divided by power. Apr 27, 2020 the formula for calculating brake specific fuel consumption is fuel consumption divided by power, and often the results are expressed in kilowatts per hour. Natural gas compressor engine survey and engine no. A key component of this alternative approach would be to collect specific emission information and develop revised emission factors for each of the or more engine models and groups determined to be significant.
What is the difference between brake specific fuel. Statistical analysis of experimental data and experimental errors. Nitrous combinations use a little extra fuel and often develop a bsfc from 0. Calculate i indicated power, ii frictional power, iii air fuel. Effect of brake power on specific fuel consumption and. However load torque 85% of the brake specific fuel consumption has decreased. The higher it is, the lower is the fuel consumption brake mean effective pressure. In this months enginology section circle track contributor jim mcfarland explains brakespecific fuel consumption bsfc and how it impacts the thermal efficiency of a racing engine circle. Thus, it should be decided that the estimated errors in the measurements of the basic and derived. Brake specific fuel consumption project gutenberg self. Effect of fuel injection pressure and injection timing of.
Also, i show oil consumption in two different ways. Fuel consumption rate 5 gs calorific value 46 mjkg net brake load 500 n torque arm 0. The bte is the ratio of power output by the engine to the amount of heat supplied by the fuel. The experiment also shows that lpg gives maximum brake thermal efficiency bte at 50% of load and 31. This is why it is recommended by iso and sae standards. The keyword brake is related to the use of a dynamometer electrical brake to measure the engine. I am now working with natural gas compressor and facing the same question. Bsfc and maximum torque should occur at or near the same rpm. In automotive applications, bsfc is used to evaluate the efficiency of the internal combustion engines ice. For spark ignition gasoline engine the bsfc is around 250 gkwh and for compression ignition diesel around 200 gkwh. Thus test has not been performed for less than 50% of full load motor.
Brake specific fuel consumption mass flow rate of fuel. It is specific in as much as it applies specifically to the weight in pounds lb of fuel needed to generate one horsepower hp for one hour hr. Sep 28, 2009 near the end, i introduced the idea of the brake specific fuel consumption bsfc to estimate the amount of fuel the engine will need per hour. Bsfc brake specific fuel consumption how is this a. No newsprint units base line year by assessment year ay 1 specific steam consumption mp kcaltonne 0 0 2 specific steam consumption lp kcaltonne 1921850 1995000 3 specific power consumption kcaltonne 1423329. As the figures show the maximum brake specific fuel consumption is more than 330 grkw.