The Effects of Diesel Fuel Properties and Engine Operating Conditions on Ignition Delay

1982 ◽  
Author(s):  
C.L. Wong ◽  
D.E. Steere
2018 ◽  
Vol 21 (7) ◽  
pp. 1118-1133 ◽  
Author(s):  
Alvaro Vidal ◽  
Carlos Rodriguez ◽  
Phoevos Koukouvinis ◽  
Manolis Gavaises ◽  
Mark A McHugh

The Perturbed-Chain, Statistical Associating Fluid Theory equation of state is utilised to model the effect of pressure and temperature on the density, volatility and viscosity of four Diesel surrogates; these calculated properties are then compared to the properties of several Diesel fuels. Perturbed-Chain, Statistical Associating Fluid Theory calculations are performed using different sources for the pure component parameters. One source utilises literature values obtained from fitting vapour pressure and saturated liquid density data or from correlations based on these parameters. The second source utilises a group contribution method based on the chemical structure of each compound. Both modelling methods deliver similar estimations for surrogate density and volatility that are in close agreement with experimental results obtained at ambient pressure. Surrogate viscosity is calculated using the entropy scaling model with a new mixing rule for calculating mixture model parameters. The closest match of the surrogates to Diesel fuel properties provides mean deviations of 1.7% in density, 2.9% in volatility and 8.3% in viscosity. The Perturbed-Chain, Statistical Associating Fluid Theory results are compared to calculations using the Peng–Robinson equation of state; the greater performance of the Perturbed-Chain, Statistical Associating Fluid Theory approach for calculating fluid properties is demonstrated. Finally, an eight-component surrogate, with properties at high pressure and temperature predicted with the group contribution Perturbed-Chain, Statistical Associating Fluid Theory method, yields the best match for Diesel properties with a combined mean absolute deviation of 7.1% from experimental data found in the literature for conditions up to 373°K and 500 MPa. These results demonstrate the predictive capability of a state-of-the-art equation of state for Diesel fuels at extreme engine operating conditions.


2014 ◽  
Vol 681 ◽  
pp. 7-10
Author(s):  
Hayat Qaisar ◽  
Li Yun Fan ◽  
En Zhe Song ◽  
Xiu Zhen Ma ◽  
Bing Qi Tian ◽  
...  

Diesel fuel pressure wave inside Combination Electronic Unit Pump (CEUP) pipeline has been investigated using a 1D viscous damped mathematical model considering the effect of four key fuel properties including density, viscosity, acoustic wave speed and bulk modulus. Wave equation (WE) based mathematical model has been developed in MATLAB using finite difference method. Mathematical model results at various operating conditions of diesel engine have been verified by comparing with those of AMESim numerical model of CEUP and quantified through Root Mean Square Errors (RMSE) and Index of Agreements (IA). Dynamic variations of these fuel properties during fuel injection cycles have also been incorporated in mathematical model by utilizing empirical formulas. Predicted results show that simulated results which consider fuel properties dynamic variations as a function of pressure are more coherent to AMESim numerical model results.


Author(s):  
Om Parkash Bhardwaj ◽  
Bernhard Lüers ◽  
Andreas F. Kolbeck ◽  
Thomas Koerfer ◽  
Florian Kremer ◽  
...  

In recent years a lot of effort has been made to understand the phenomena of Diesel Particulate Filter (DPF) regeneration processes but less attention has been paid to understand the influence of fuel properties on soot reactivity and its consequence on the DPF regeneration behavior. Within the Cluster of Excellence “Tailor-Made Fuels from Biomass (TMFB)” at RWTH Aachen University, the Institute for Combustion Engines carried out a detailed investigation program to explore the potential of future biofuel candidates for optimized combustion systems. These new biofuels are being developed to realize partially homogeneous low-temperature combustion, in order to reduce the emission and fuel consumption to meet future requirements. The chemical structure of these new fuels may impact the thermal decomposition chemistry and hence the in-cylinder particulate formation conditions. This work fundamentally focusses the influence of fuel properties on particulate matter reactivity and, thereby, the regeneration behavior of the diesel particulate filters (DPF). The experiments for particulate measurements and analysis were conducted, under constant engine operating conditions, on a EURO 6 compliant High Efficiency Combustion System (HECS) fuelled with petroleum based diesel fuel as baseline and today’s biofuels like FAME and Fischer Tropsch fuels as well as potential biomass derived fuel candidates being researched in TMFB. Several different methods were used for analysis of mass, composition, structure and spectroscopic parameters of the soot. The graphitic microstructure visible with high resolution transmission electron microscopy (HRTEM) was compared to the results of X-Ray diffraction (XRD), optical light absorption measurement and elementary analysis of samples. The results indicate that combustion with increasing fuel oxygenation produces decreasing engine-out particulate emissions. The ranking of activation energies of soot oxidation analysis from LGB experiments correspond well with the ranking of the soot physico-chemical properties. In comparison to petroleum based diesel fuel, the reduction of engine out soot emission by a factor of five with the use of the future biomass derived fuel candidate was accompanied by ten times reduction of the soot volume based absorption coefficient and two times reduction of carbon to hydrogen ratio. As a result of it, the activation energy of soot oxidation in DPF reduced by ∼ 10 KJ/mol. The reduced engine out soot emission and increased reactivity of the soot from the future biomass derived fuel candidate could cause a significant reduction of thermal DPF regenerations.


2020 ◽  
Vol 10 (2) ◽  
pp. 50
Author(s):  
Menelik Walle Mekonen ◽  
Niranjan Sahoo

In this paper, energy, exergy, suitability and economic evaluation of a diesel engine running with diesel fuel and five different types of preheated biodiesel blends were evaluated experimentally. The experiments were carried out at varying engine brake mean effective pressures (bmeps). The energy and exergy rate components of the engine were callcualted and compared for each operating conditions and blends of fuel. The fuel properties of the castor oil methyl ester (COME) at different preheating temeperatures have been tested with a consideration of different biodiesel international standards. The test results shows that the fuel properties of COME improve with increase of fuel inlet temeperatures. At 114°C, kinematic viscosity and density decreased to (5.74 mm2/s and 862 kg/m3), whcich is close to diesel fuel, and the brake specific fuel consumption (BSFC) and brake thermal efficiency (BTHE) was improved by 33.1% and 49.6% compared to the fuel preheated temeperature of 42°C. The input fuel energy and exergy rates of blends of fuel were seen to be improved than diesel fuel. The maximum energetic and exergetic efficiency for blended fuels in the test engine at 372 bmep were found in the range of 25−28 % and 23-26%, respectively. The blends of fuel are marginally less sustainable than diesel fuel at every bmeps. The cost analyses show that, all blends of fuel offer quite higher economic cost with respect to diesel fuel. The full economic analysis reveals that only up to 60% blends of fuel is more affordable as compared to diesel.


2014 ◽  
Vol 3 (10) ◽  
pp. 3419
Author(s):  
Mohan Reddy Nalabolu* ◽  
Varaprasad Bobbarala ◽  
Mahesh Kandula

At the present moment worldwide waning fossil fuel resources as well as the tendency for developing new renewable biofuels have shifted the interest of the society towards finding novel alternative fuel sources. Biofuels have been put forward as one of a range of alternatives with lower emissions and a higher degree of fuel security and gives potential opportunities for rural and regional communities. Biodiesel has a great potential as an alternative diesel fuel. In this work, biodiesel was prepared from waste cooking oil it was converted into biodiesel through single step transesterification. Methanol with Potassium hydroxide as a catalyst was used for the transesterification process. The biodiesel was characterized by its fuel properties including acid value, cloud and pour points, water content, sediments, oxidation stability, carbon residue, flash point, kinematic viscosity, density according to IS: 15607-05 standards. The viscosity of the waste cooking oil biodiesel was found to be 4.05 mm2/sec at 400C. Flash point was found to be 1280C, water and sediment was 236mg/kg, 0 % respectively, carbon residue was 0.017%, total acid value was 0.2 mgKOH/g, cloud point was 40C and pour point was 120C. The results showed that one step transesterification was better and resulted in higher yield and better fuel properties. The research demonstrated that biodiesel obtained under optimum conditions from waste cooking oil was of good quality and could be used as a diesel fuel.


Author(s):  
Vishal V Patil ◽  
Ranjit S Patil

In this study, different characteristics of sustainable renewable biodiesels (those have a high potential of their production worldwide and in India) were compared with the characteristics of neat diesel to determine optimistic biodiesel for the diesel engine at 250 bar spray pressure. Optimistic fuel gives a comparatively lower level of emissions and better performance than other selected fuels in the study. Rubber seed oil methyl ester was investigated as an optimistic fuel among the other selected fuels such as sunflower oil methyl ester, neem seed oil methyl ester, and neat diesel. To enhance the performance characteristics and to further decrease the level of emission characteristics of fuel ROME, further experiments were conducted at higher spray (injection) pressures of 500 bar, 625 bar, and 750 bar with varying ignition delay period via varying its spray timings such as 8°, 13°, 18°, 23°, 28°, and 33° before top dead center. Spray pressure 250 bar at 23° before top dead center was investigated as an optimistic operating condition where fuel rubber seed oil methyl ester gives negligible hydrocarbon emissions (0.019 g/kW h) while its nitrogen oxide (NOX) emissions were about 70% lesser than those observed with neat diesel, respectively.


Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 452
Author(s):  
Luka Lešnik ◽  
Breda Kegl ◽  
Eloísa Torres-Jiménez ◽  
Fernando Cruz-Peragón ◽  
Carmen Mata ◽  
...  

The presented paper aims to study the influence of mineral diesel fuel and synthetic Gas-To-Liquid fuel (GTL) on the injection process, fuel flow conditions, and cavitation formation in a modern common-rail injector. First, the influence on injection characteristics was studied experimentally using an injection system test bench, and numerically using the one-dimensional computational program. Afterward, the influence of fuel properties on internal fuel flow was studied numerically using a computational program. The flow inside the injector was considered as multiphase flow and was calculated through unsteady Computational Fluid Dynamics simulations using a Eulerian–Eulerian two-fluid approach. Finally, the influence of in-cylinder back pressure on the internal nozzle flow was studied at three distinctive back pressures. The obtained numerical results for injection characteristics show good agreement with the experimental ones. The results of 3D simulations indicate that differences in fuel properties influence internal fuel flow and cavitation inception. The location of cavitation formation is the same for both fuels. The cavitation formation is triggered regardless of fuel properties. The size of the cavitation area is influenced by fuel properties and also from in-cylinder back pressure. Higher values of back pressure induce smaller areas of cavitation and vice versa. Comparing the conditions at injection hole exit, diesel fuel proved slightly higher average mass flow rate and velocities, which can be attributed to differences in fluid densities and viscosities. Overall, the obtained results indicate that when considering the injection process and internal nozzle flow, GTL fuel can be used in common-rail injection systems with solenoid injectors.


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