Brake specific fuel consumption

Fig. 2. Effect of mixture strength on exhaust gas composition (dry basis) and brake specific fuel consumption (BSFC) for an unsupercharged automotive-type engine usiag iadolene fuel, H/C = 1.86, where the ignition is tuned to achieve maximum best torque (MBT), the brake mean effective...

Brake-Specific Fuel Consumption (BSFC) This is a measure of the pounds of fuel consumed per brake horsepower for a one hour period. 

THC total hydrocarbon BSFC brake specific fuel consumption Tha lower BSFC number for F-T diesel should partially offset the disadvantage of its lower heating value. 

Fuel consumption rates on diesel engines are generally specified as brake-specific fuel consumption and its units are in pounds per brake horsepower hour, grams per brake horsepower hour, or grams per kilowatthour. (See Fig. 6.92.)... 

Cottonseed methyl esters were tested in a four-stroke locomotive diesel resulting in a 0.7% loss of thermal efficiency, 32% reduction of particulate matter emissions, increase of NO c emissions as a function of several combustion parameters (eg, O/C ratio or injection timing) and a brake specific fuel consumption (BSFC) 13.4% higher than pure petrodiesel (Gautam and Agarwal, 2013). 

The effect of biodiesel fuel from Jatropha curcas oil in DI diesel engines on the components of the engine influenced by fuel before (injection pump, injector) and after the combustion process (piston crown, cylinder head) were studied (Reksowardojo et al., 2005a,c). The test bed procedure used was that commonly used for injection cleanliness evaluation adopted by World-Wide Fuel Charter (December 2002) (ACEA, 2002). Exhaust gas emissions such as nitrogen oxides (NO c), carbon monoxide (CO), brake-specific fuel consumption (BSFC), and engine lubricant before and after the test were also measured. 

Figure 23.19 Comparison of engine power and brake-specific fuel consumption as the same engine mn with market diesel and biodiesel B5 fuel.

The concept of the S-curve will be explained in general terms. We will consider here a relationship (a function) between a dependent variable, called simply variable, and an independent variable, which is in our case time. The nature of the relationship is the same for several kinds of variable. The variable may represent the performance of the system (for a car maximum speed, braking distance, fuel consumption, etc.) or its various features (e.g., weight, length, or volume). The variable may also represent the rate of change of the performance or of a feature of the system, particularly when we are interested in the dynamics of change. Finally, variable may mean the cumulative value of a specific characteristic of the system, for example, the number of patents associated with the system. 

The results presented in this chapter are based on a GT-Power model of a six cylinder heavy-duty diesel engine with a variable geometry turbocharger (VGT) and an exhaust gas recirculation (EGR) system. This model was calibrated using steady-state data collected experimentally and then validated using transient data. For the steady-state calibration, each of the actuator models were tuned to ensure that the VGT and EGR actuators affect the air path in a manner consistent with the experimental data. Quantities such as the fresh air flow, EGR flow, turbine speed, exhaust pressure and intake pressure were all analyzed. Because the specific fuel consumption and NOx production predictions are so important to the selection of the fueling parameters, particular attention was given to the predictive combustion model. The correlations between the experimental and predicted brake spjecific fuel consumption... 

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