Papers by Keyword: Fuel Consumption

Abstract: The paper presents a developed method for assessment of gas distribution over the cross section of a shaft furnace working in the countercurrent conditions. This method is scientifically based on the fundamental principles of the countercurrent heat exchange theory in shaft furnaces, i.e. dependences of the temperature field throughout the burden bed height on the ratio between heat capacities of gas and burden flows. The ratio between the gas flow heat capacity and burden flow heat capacity at the stock line level is determined by the averaged gas temperature at the burden bed output. By comparing these data, we estimated directions for improving the gas distributing system. Efficiency of this method was assessed when analyzing the system of air supply to the shaft furnace at one of the Ural plants. The analysis showed the main drawbacks of the existing gas distributing system and enabled to determine the main directions for reconstruction of this system. On the basis of the analysis results related to operation of the tuyeres and distribution manifold, we proposed more efficient options of their parameters, i.e. manifold cross-section area, tuyere number and diameter, angle of tuyere inclination to the horizontal. These changes provided a uniform distribution of gases across the furnace and improved conditions for melt flow in the furnace. Thus, we established virtually equal conditions for development of heat and mass transfer processes in the work space of the shaft furnace. The modernized system of air supply to MMSK’s shaft furnace increased the furnace performance by 14.14% in terms of burden, by 23.27% in terms of matte, by 15.15% in terms of slag and by 6.65% in terms of thermal efficiency. At the same time, the following parameters were reduced: specific fuel consumption (anthracite) by 17.46% and dust discharge by 40.5%. When supplying air to the furnace through the inclined tuyeres, it became possible to reduce formation of accretions and provide new working conditions for operating personnel due to a more uniform gas distribution across the horizontal section of the furnace. Within six months of furnace operation the personnel had no problems related to its operation.

Abstract: The present study has been attempted to systematically perform a visualizing analysis plan which can improve the flow rate, velocity and mass flow rate as a function of the size of the welding section in the injector as a key for the determination of the injection amount and time of the fuel (CH₄) system for natural gas. As the setting conditions for the analysis, a minimum pressure of 2 bar and a maximum pressure of 8 bar were set to be the total pressure values in the case of the inlet, while 0 bar was set for opening drain to represent the state in the atmosphere in the case of the outlet. As a result, the characteristics with an increase in velocity could be affirmed as strong flow separation and eddy current were produced according to the model with a large size of welding section. An excellent performance with an improvement in the performance of velocity flow rate by about 40% could be affirmed in the model where the size of the welding section was designed to be 6 EA.

Abstract: Every engine needs a cooling system in order to maintain the performance of engine. In this study the cooling system is applied in naval ship with the exchange of freshwater and seawater. Since the seawater contains biological fouling, then it is scaled in the heat exchanger so that the performance of heat exchanger is decreasing from time to time. This makes the heat transfer rate in cooler is less efficient so that to maintain the BHP of the engine it needs to consume more fuel. The result shows that the effect could incur a loss of about USD 463,852.8/month. This condition makes the importance of cooling system maintenance in order to keep the temperature of the naval ship engine and to minimize the additional fuel cost. For cooling system itself, to keep the cooler in a good condition, it needs to clean the cooler for every 720 hours, or once a month.

Abstract: An automotive air conditioning system that uses thermal expansion valve (TEV) as an expansion device. The pressure drop from the condenser and evaporator pressure is considered an isenthalpic process (constant enthalpy), where this process causes energy loss (entropy generation) in the expansion process. The ejector recovers energy losses, which was previously lost in the expansion valve, and an ejector can be used to generate isentropic condition in the expansion process. The use of an ejector as an expansion device in this study can reduce power consumption of the compressor and increase cooling capacity of the evaporator. The experiments were conducted with temperature set-points of the conditioned space of 21, 22 and 23°C with internal heat loads of 100, 200 and 400 W. Measurements were taken during the one hour experimental period at a time interval of five minutes. The experiment results indicate that the ejector system is better than TEV and save fuel.

Abstract: The study sets the objective of overall overrun fuel separation into two components. The first one depends on changes in the electric load of the power unit. The second component is influenced by changes of the power unit controlled parameters. The separation leads to the adjustment of technical and economic performance of the power plant unit. These indicators show both the efficiency of the power unit and the overall plant.

Abstract: Turbochargers are an integral part of today’s modern diesel engines and are a major reason that they are able to produce more power. Unlike a super charger that is driven via a belt from the engine, a turbo takes the exhaust that the engine is producing and puts it to good use. As Turbochargers are driven by exhaust, heat is an unwelcome by product and something that wasn’t really taken into account in automobiles. Then those intercoolers started to come into play in turbocharged automobiles. The forced air produced by the turbocharger is routed through the intercooler where its temperature is reduced before reaching the engine. The use of intercoolers has made turbocharged vehicles far more reliable and, in the case of today’s heavy duty diesel trucks, is a very important component. The inlet air of an IC engine from turbocharger temperature is very much high (due to compression) means oxygen content is very much less. And also air with high temperature causes pre-ignition and detonation. So fuel combustion does not take place properly. Inter Cooling of inlet air is very much essential according to performance point of view. Turbo intercoolers are used for cooling the inlet air of an IC engine from turbo chargers. Moreover cooling of air makes it denser and contributes for better combustion and more power they are mounted close to the radiators for achieving lower air temperature. This arrangement affects the performance of both. So in this project an attempt will be made to increase the efficiency of the turbo intercooler arrangement through design modification and repositioning of intercooler by taking the TATA MARCOPOLO-Star Bus 909 as a reference.

Abstract: As it is generally known, diesel engines operate with air excess, i.e. lean mixtures. Intake resistances in intake manifolds of diesel engines negatively influence their ecological parameters. Based on these facts, we may conclude that less air in the intake manifold causes increased production of exhaust fumes and fuel consumption. One of the reasons of increased intake resistance is a blocked air filter. In the experiment, we have simulated the increased intake resistance and wished to point out possible consequences of pressure drop at the end of the compression stroke. The choking effect was realized by means of a throttle and scale, which was mounted on the air filter position. By using the dynamic method and obtained results, we found that choking at the rotation angle of 90° and 45° caused the difference of 0.16 MPa of the measured quantity during the maximum revs set on 2000 min^-1. The difference in pressure at the end of the compression stroke with the rotation angle of 30° and 90° was by 0.86 MPa higher. Pressure drop in manifold showed the value 0.15 MPa. Manufacturers recommend regular replacement of air cleaners of combustion engines in service intervals; however, we must also keep in mind the environment in which the engine operates. In excessively dusty and otherwise polluted areas, it is necessary to replace cleaners a bit earlier.

Abstract: To predict accurately the fuel consumption rate of a diesel engine, based on polynomial fitting curve method, combined with the test data of XCW6200ZC medium speed marine diesel engine used for inland ships, a diesel engine fuel consumption model about characteristic coefficient and speed under the propulsion characteristic was established. The marine diesel engine fuel consumption were calculated and predicted through this model. The results showed that the model can predict the fuel consumption of diesel engine well.

Abstract: In the background of the main technologies of fuel economy in automobiles developed to a certain stage, it is necessary to reduce fuel consumption and increase the engine efficiency by developing other auxiliary technologies such as improving the ratio of pure energy drive, low rolling resistance tires, tire pressure monitoring system and gear shift indicators (GSI). This article introduces the principle of GSI, analyses how GSI works in improving engine efficiency, and then evaluates the method for determination of the relative saving rate of fuel consumption, which method was introduced in the EU regulation EC No. 65/2012.

Abstract: The paper studied the effect of fuel injection pressure and fuel supply advance angle on characteristics of butanol diesel blend engine.First,the results shows that when the volume ratio of butanol diesel is constant ,the fuel consumption and HC emission are the least under 20°CA.With increase of fuel supply advance angle ,the exhaust smoke emission and CO emission decreased largely under high load, but NO_X emission increased largely. When the fuel supply advance angle is constant ,with the increase of volume ratio of butanol diesel ,the fuel consumption increased gradually, the exhaust smoke emission decreased largely, HC emission increased clearly, CO emission decreased largely but NO_X emission increased.Third,with increase of fuel injection pressure,the exhaust smoke emission decreased largely ,NOx emission changed a little ,CO and HC emission increased largely.