Performance of Common Rail Direct Injection (CRDi) Engine Using Ceiba Pentandra Biodiesel and Hydrogen Fuel Combination

An existing diesel engine was fitted with a common rail direct injection (CRDi) facility to inject fuel at higher pressure in CRDi mode. In the current work, rotating blades were incorporated in the piston cavity to enhance turbulence. Pilot fuels used are diesel and biodiesel of Ceiba pentandra oil (BCPO) with hydrogen supply during the suction stroke. Performance evaluation and emission tests for CRDi mode were carried out under different loading conditions. In the first part of the work, maximum possible hydrogen substitution without knocking was reported at an injection timing of 15° before top dead center (bTDC). In the second part of the work, fuel injection pressure (IP) was varied with maximum hydrogen fuel substitution. Then, in the third part of the work, exhaust gas recirculation (EGR), was varied to study the nitrogen oxides (NOx) generated. At 900 bar, HC emissions in the CRDi engine were reduced by 18.5% and CO emissions were reduced by 17% relative to the CI mode. NOx emissions from the CRDi engine were decreased by 28% relative to the CI engine mode. At 20%, EGR lowered the BTE by 14.2% and reduced hydrocarbons, nitrogen oxide and carbon monoxide by 6.3%, 30.5% and 9%, respectively, compared to the CI mode of operation.

Impact of Fuel Injection Pressure on Spray and Combustion Characteristics of OME and Diesel Blends

Emission regulations focus on the simultaneous reduction of NOx and particulate matter emissions, especially for heavy-duty engines. Oxygenated fuels offer significant advantages in reducing particulate emissions while having little effect on NOx emissions. In addition, renewable fuels present a GHG emission advantage to meet the zero-emission requirements of future hydrocarbon fuels. Among the leading contenders, oxymethylene dimethyl ether (OME) fuels have the potential to be used for direct injection applications. OME as a blend with diesel fuel offers a direct means of improving the emissions of current on-road diesel engines without modification. In this paper, an empirical investigation into spray behavior and engine performance of diesel/OME fuel at 10% by mass has been performed under various fuel injection pressures. Neat diesel fuel was tested as a baseline case. The results are compared to tests under matching conditions using a diesel and OME fuel blend with a focus on spray characteristics, combustion behavior, and engine-out emissions. The physical properties of OME improve the volatility of diesel fuel and can tolerate shorter mixing times without promoting PM production. The PM emissions were found to be reduced by up to 50% and the combustion efficiency was improved at matching NOx levels with OME blending.

Experimental Stand to Investigate the Injection Process in Diesel Engines

The objective of this paper is to investigate the fuel injection system in diesel engines by using inline pumps. In a diesel engines, the fuel injection pressure plays an important role in the combustion process in order to obtain high performance and low fuel consumption. The experiments in this paper are been performed on a 6 cylinder inline pump which is actioned by an electric motor with variable r.p.m.-s The quantity of the fuel injected by each injector is measured function of time and the speed of electric motor. The experiments show the degree of non-uniformity of the fuel delivered by the pump to injectors.

Effect of process parameters on the diesel engine performance fuelled with Prosopis juliflora biodiesel response surface methodology approach

The rapid consumption of crude oil and resulting pollution are very severe problems in modern energy sectors. To meet these global problems, biodiesels obtained from non-edible plants can play a very crucial role. Keeping this idea in mind the present study focuses on making some efforts for the best utilization of innovative blends of Prosopis juliflora biodiesel in the operation of diesel engines. Four engine input parameters viz. fuel injection pressure (16–24 MPa), P. Juliflora biodiesel blends (0–10%), shaft loads (20–100%) and injection timing (15–31°bTDC (before top dead centre)) are selected for optimization process. The experiments were executed in accordance with response surface methodology. The results of the experiments revealed that the optimum combination for engine input parameters were at fuel injection timing 30°bTDC, fuel injection pressure 22 MPa, 4% P. juliflora biodiesel blending at 59% of engine load to achieve best performance. The individual desirability of brake thermal efficiency, brake specific fuel consumption, exhaust gas temperature and peak cylinder pressure were found to be 0.888, 0.949, 0.624 and 0.749, respectively, and the composite desirability of engine responses was found to be 0.7923 which makes the results acceptable.

Experimental Investigation on Emission Characteristics of Diesel N-Pentanol Blend in Homogeneous Charged Compression Ignition Engine

The invention of internal combustion engines is undoubtedly one of the greatest inventions of the modern era. There has been steady scientific research to look for alternative fuel which is economical, renewable and less harmful to nature and man compared to fossil fuels. The present project is one such experimental work to investigate the performance of a blend of diesel / N-pentanol in an appropriate combustion technique and to establish its suitability as a renewable fuel. The relative performance of diesel fuel and the blend of diesel / n-pentanol will also be analyzed. Diesel fuel blended with 30 percentage n-pentanol is the fuel blend that is proposed to be used in the experiment. Researchers have established that the application of Homogeneously Charged Compression Ignition (HCCI) technique could result in in-cylinder reduction of NOx and PM. Higher thermal efficiency could also be attained. The project also covers studying the emission effect of the diesel/n-pentanol fuel blend for various fuel injection timing, various fuel injection pressure, different EGR rates and different inlet air temperature.

Enhancement of combustion characteristics of VCR diesel engine by optimizing engine parameters

In recent years, engine emissions have been one of the important problems which are of great concern. Hence, there is a growing need to develop engines with reduced emission. In the present study, Variable Compression Ratio diesel engine model has been validated by comparing the simulation results with the experimental. The study is aimed at analyzing the effect of compression ratio, exhaust gas recirculation, fuel injection pressure and start of injection on engine performance and emission characteristics. Using composite desirability technique, the engine parameters have been optimized to achieve lower NOx, soot and ISFC. The optimum combination has been observed at Compression ratio 17.52, Start of injection −30.1 °aTDC, Fuel injection pressure 736.06 bar and Exhaust gas recirculation 28.29%. ISFC, NOx and soot are reduced by 2.37%, 29.11% and 83.81% respectively. Higher Target Fuel Distribution Index indicates the improved mixture homogeneity for the optimized parameters.

Effect of Intake Air Temperature, Pressure And Fuel Injection Pressure On Low Temperature Combustion (LTC) Engine BY Using Dual Injection Strategy For Pollution Reduction

Starting from the invention of engines, automobiles require engines for their application. Even though several alternatives have been proposed like fuel cells, engines play the vital role in the automobile sector. In this scenario, the emissions coming out from the engine contributes to the global air pollution at an unbelievable rate. This led the government to enforce strict emission regulations on automobiles. To achieve those regulations several ideas have been proposed so far, which are generally classified into two categories as in-cylinder measures and after-treatment measures. But the thing is after-treatment measures are too costly and also it mainly depends on combustion rate. So obviously in-cylinder controls will be the potential area for the research. Automobile sector not only focused on emissions; it also wants high thermal efficiency in engine. Due to high thermal efficiency and good fuel economy diesel engines are the favorite one in automobiles. But it emits NOx and PM at higher rate. To overcome this issue low temperature combustion (LTC) concept is introduced, added to the objective it can also maintain high thermal efficiency as like as diesel combustion. The problem regarding to LTC are combustion phasing control, transient operations, limited operating range and mainly it contributes to HC and CO emissions while concentrating on reduction of NOx and PM. In the present work, control emissions and combustion phasing of LTC combustion concept by dual injection strategy was studied and the effect of fuel injection pressure, intake air temperature and pressure also studied. The project was done only on partial load with diesel as fuel. Late injection strategy of LTC was used. Results shown that compared to single injection strategy, thermal efficiency was improved by dual injection strategy. Pilot injection timing and mass fraction played a vital role in controlling emissions and improving thermal efficiency. In all intake air temperature, if fuel injection pressure increase result in increase of thermal efficiency, NO emission and decrease of smoke, CO and HC emissions. Likewise in all intake air temperature and fuel injection pressure, if Intake air pressure increase result in increase of thermal efficiency, smoke and decrease of NO, HC and CO emissions. Maximum Indicated thermal efficiency achieved was 38% which was 8% higher than base readings. Lowest NO emission achieved was 187 ppm, that was 68% less than base reading. Lowest smoke achieved was 3% of opacity, which was 75% less than base reading. An overall comparing result, optimized fuel injection pressure is 600 bar, intake air temperature is 310 K, intake air pressure is 107 kPa. At that condition, smoke reduced to 23%, NO reduced to 63%, CO reduced to 75% and indicated thermal efficiency increased to 4% compare to base readings.

Performance and Emissions Analysis of 4-Stroke Biodiesel Engine at Different Injection Pressure

Alternative fuels for diesel engines have become increasingly important due to several socioeconomic aspects, imminent depletion of fossil fuel and growing environmental concerns. Global warming concerns due to the production of greenhouse gases (GHGs) such as carbon dioxide (CO2) as results from internal combustion engine have seen as one of major factor the promotion of the use of biofuels. Therefore, the use of biodiesel fuel (BDF) as an alternative for fossil diesel (DSL) is among the effective way to reduce the CO2 emission. In this experimental study, the effects on engine performance and fuel-induced emission characteristics were studied using fuel blends and under different fuel injection pressure. Even though the brake thermal efficiency was obtained maximum for the conventional diesel at standard operating condition, the same can also be achieved with biodiesel blends by increasing the injection pressure higher than that of the level used for conventional diesel. This experimental test was done using a small 4-stroke single cylinder diesel engine with electric dynamometer loads integrated with emission gas analyser that attached to the exhaust pipeline. As results of experimental investigations, decreasing in NOX Emission, SOX Emission, CO Emission and also brake specific fuel consumption compare to pure diesel.