Papers by Keyword: Diesel

Abstract: The use of blended palm biodiesel has been implemented in Malaysia starting with B5 (5% palm biodiesel blended with 95% petroleum diesel) in 2011, B7 (7% palm biodiesel blended with 93% petroleum diesel) in 2014, and B10 in 2019. Palm biodiesel has been regarded as a reliable petroleum diesel substitute since 1995 following the research and development carried out by MPOB. Six trucks participated in the trial to evaluate the use of B20 and B10 through fleet testing and laboratory investigations. The trucks were divided into two groups according to fuel used. The field trial started in 2019 and ended in 2021. Engine oil and filter samples were taken at 5,000 kilometers intervals between service interval 30,000 kilometers. All the engine oil samples were within their operational service limits at each 5,000 kilometers sampling interval. The average viscosities of used engine oil in B20 group were 12.75 mm² s^-1 and for B10 group 12.98 mm² s^-1. The total basic number (TBN) values for the B20 group was 6.4 mg KOH g^-1 and 6.3 mg KOH g^-1 on average for B10 group. The wear and contaminants test showed the average iron particles concentrations for B20 and B10 groups were 22 ppm and 25 ppm respectively. In terms of engine oil evaporation, the average zinc and phosphorus concentrations reduced by only 20% for both vehicle groups. The average values for soot in oil showed that the B20 group had 10% less soot build-up compared to B10 group. The use of B20 had affected engine oil quality with minimal advantages for soot in oil and iron particle concentrations.

Abstract: The article analyzes the reasons hindering the mass use of alternative fuels in the field of energy consumption of domestic transport, which for the most part have lower energy and kinetic indicators of combustion in comparison with traditional fuels. A new approach to solving the problem of improving the environmental and energy-saving indicators of combustion of alternative fuels based on their preliminary thermochemical processing - conversion on board a vehicle is presented. The results of a preliminary analytical study of the parameters of the on-board conversion process for a number of potentially acceptable types of alternative fuels are presented in order to assess the efficiency of this process. The possibility of practical implementation of the proposed process for improving the combustion indicators of alternative fuel with an assessment of its efficiency was tested based on the results of experimental approbation in the conditions of full-scale engine tests. According on the results of the study, the expediency of using this process in transport technologies is justified due to the technical simplicity of its implementation and efficiency. Thermocatalytic reactor is the simplest design of a heat exchanger, the mass and dimensional characteristics of which (in the volume of a conventional muffler) ensure the convenience of its installation in the engine exhaust system. The component composition of these products contains reactive compounds that contribute to the improvement of environmental and energy-saving indicators of the fuel combustion process, and an increase in the efficiency of the engine's operating cycle.

Abstract: The primary task in DI (Direct Injection) diesel engines design is the fulfilment of the required emission limits. This result should be achieved with acceptable power-to-rpm diagrams, acceptable fuel consumption, acceptable power density and affordable purchase and maintenance expenses. The most common approach to fulfil these requirements is the downsizing. In this case a significant increase in the crankshaft speed and boost pressure is unavoidable. In this way, an improvement in airflow through the redesign of the intake and exhaust geometry is obtained. Unfortunately, duct design is extremely difficult due to “Mach lock”. A further important boundary condition is due the injector inertia. The dynamic response improves with small injectors due to the Newton’s second law. Small injectors designed for unitary power of 15 to 70 HP are extremely common. Therefore, most of the research is centered on these injectors. Furthermore, their small inertia favors better opening and closing time. Nozzles number and position is also greatly influential on combustion performance. The larger surface of the spray reduces the gasification time of the droplets. For these reasons, multiple injectors systems may be used in large high pressure HSDI-CR (High Speed Direct Injection – Common Rail) diesels. Multi injection was commonplace in relatively large old diesels. This paper proposes new intake duct geometries for modern two-injectors-per-cylinder truck-size engines. For this purpose a new promising, patented concept is introduced. The study includes flow simulations during the intake phase. This patented geometry induces the presence of two extremely strong swirls approximately centered to the injectors, with excellent swirl coefficient and high flow rate. The use of swirl generators on the manifolds avoids the necessity to design helical intake ducts. This patented approach simplifies head design. Moreover, using a VG (Variable Geometry) arrangement for the volutes (swirl generators) it is possible to tune the swirl index at the optimum for every crankshaft velocity and every load. In this way, the vehicle fuel consumption is also reduced.

Abstract: Small diesel engines with direct injection air cooled a big problem is heat dissipation. Based on bench made ​​with a 295 cc diesel engine with direct injection, air cooled, I set the heat flows through the cylinder head, piston and cylinder. These data are needed to study the possibility of operating at maximum power, knowing that mechanical stresses of thermal origin are the most dangerous. The data obtained in this work will be used in the analysis of temperature and stress fields.

Abstract: The increasing price of the fuels and tightening of the pollution rules requires the use of some efficient fuelling methodes with altenative fuels for diesel engines. Fuelling with LPG of a diesel engine is a viable sollution, considering that it can be used the infrastructure for distribution and storage already used for spark ignition engines. In this work are presented results of theoretical and experimental investigations of a truck diesel engine fuelled with LPG by diesel-LPG methode. The main objective research is the decrease of the nitric oxides emissions with the premise that the engine power is maintained at the same level like in the case of the standard engine, fuelled only with diesel fuel.

Abstract: The consequential use of biodiesel as a source of renewable energy sustained a rapid growth over the past few years due to its major advantages like biodegradability, higher lubricity, low toxicity and low CO₂ emissions. Generally, transesterification is used for the production of biodiesel by employing base catalysis. Here, this Biodiesel is prepared from Annona Squamosa (Custard apple) seed oil with methanol by using potassium hydroxide as a catalyst which is further tested in Compression Ignition (C.I) engines. In the present study, an attempt has been made to analyze the acoustical studies on various blend compositions of Biodiesel with conventional diesel in the ratios 0%, 20%, 40%, 60%, 80% and 100% by determining relative viscosity, ultrasonic velocity and density at 303K. From these experimental data, various molecular interaction parameters like adiabatic compressibility, viscous relaxation time, inter molecular free length, specific acoustical impedance are calculated and the results are discussed in the light of solute-solvent interaction.

Abstract: In this work biodiesel of various proportions has been blended with E20 (20% ethanol and 80% diesel). Bio-diesel concentrations are varied at 10%, 20% and 30% while ethanol concentration was maintained at 20%. Performance, emission and variation of ignition lag of the fuel blends were analyzed. There was a very good reduction in CO emissions by 28% in comparison with E20 and 80% in comparison with diesel. NOx emissions of the blends were decreased by 16% compared with diesel and no variation with E20. Brake Thermal Efficiency (bte) of the blends was higher by 11% up to 75% load and 4% at full load compared with diesel and lesser by 2% in comparison with E20. Ignition-delay of the blends was longer than diesel, and the cetane number of the blends were lower than diesel. Brake Specific Energy Consumption (bsec) is slightly higher than diesel.

Abstract: Biodiesel fuel can be used in diesel engine in accordance to the standard provided. However, a significant issue with biodiesel fuel was noted. Some of the fuel quality were outside the accepted range of the specification stated in the standard. Thus, this can be lead to the problem of utilization them in diesel engine. Moreover, material compatibility is the main concern whenever the fuel composition is altered in the fuel system. A large variety of metals and non-metals are worn as the material of construction for the various components of the fuel system. Introduction of biodiesel fuel often generate many problems in the components of the fuel system. This paper attempts to present the compatibility issue related to the use of biodiesel with automotive materials.

Abstract: Cashew nut shell oil (CNSO) is potential alternative fuel for diesel engine. Its drawback is incomplete combustion and low brake thermal efficiency (BTE) due to high viscosity. To overcome this problem the CNSO was blended with diethyl ether (DEE) which is less viscous and burns easily. The influence of blends on CO, NOx and smoke emission is investigated by emission tests. The fuel containing 20% CNSO and 80% diesel fuel (B20), 95% B20 and 5% DEE by volume (B20D5), 90% B20 and 10%DEE by volume (B20D10) 85% and B20 and 15% DEE by volume (B20D15) are tested. Initially the experiment was conducted with different blends of CNSO-diesel blends like 10%, 20%, & 30% by volume basis in a diesel engine.The aim for the research of alternative fuel is to replace the sufficient amount of diesel fuel without affecting the existing engine performances. Increasing CNSO diesel blends performances reduces marginally. B10 shows more closer performances to diesel fuel, but replacement of 10% only diesel is not much. Using B30 and higher blends gives poor result. Hence it was decided to be B20. In the second stage B20 as a base fuel and it is blended with DEE 5%, 10% & 15% by volume basis at different load conditions. The result shows that B20D15 has BTE 26.50% which is very close to the base diesel fuel. The B20D15 emits 1200 PPM of NOx while diesel emits 1195 PPM but B20 emits 1450 PPM of Nox. Carbon monoxide (CO) emission also reduces for different blends of DEE. The smoke emission is 3.96, 3.38, 3.15 FSN of B20, B20 D15 and diesel respectively.

Abstract: The paper presents a method of transforming the time axis to the axis of the crank angle rotation based on the pressure measured in time domain and simplified model of the engine dynamics. Indicating is to register the pressure in synchronism with the engine crank angle rotation. Usually in the ad hoc measurements the crankshaft rotation angle transducer is avoided, and the measurements are performed in time domain. For further analysis time axis is transformed for crank angle axis on the base of linear transform. Pressure waveforms obtained during the research were subject of the described transform. During the research instantaneous angular speed (IAS) of the engine crankshaft has been changed by reducing fuel dosage to selected cylinders. Mean indicated pressure (MIP) was calculated. Values o pressure on the begging and the end of compression, opening and closing angles of valves were also determined.