Rahul Banerjee

An Experimental Investigation on the Potential of Hydrogen in the Reduction of the Emission Characteristics of an Existing Four-Stroke Single-Cylinder Diesel Engine Operating Under EGR

The present work attempts to explore the emission characteristics of an existing single-cylinder four-stroke compression-ignition engine operated in dual-fuel mode with hydrogen as an alternative fuel. Experimental investigation was carried out with the engine being subjected to different loads at a predefined flow rate of hydrogen induction. The emission characteristics revealed a 71% and a 40.5% reduction of CO2 emissions at 20% and 80% load, respectively, for non-EGR (exhaust gas recirculation) hydrogen enrichment. In CO emissions, non-EGR hydrogen enrichment registered a 69.5% and a 64.3% reduction at 20% and 40% load, respectively. Smoke emissions saw a 61.5% and a 64.3% reduction during non-EGR hydrogen enrichment at 20% and 40% load, respectively. Hydrocarbon (HC) emissions were reduced by 80% and 60.9% as compared with diesel operation at 20% and 60% loads, respectively. Hydrogen enrichment operations without EGR were penalized, however, with an increase of 79.3% and 81.3% in NOx at 40% and 60% load, respectively, as compared with diesel operation. EGR (hot and cold) technique has been implemented in the present work to reduce NOx emissions. In the present study, hydrogen enrichment overcome the inherent penalization of NOx–smoke tradeoff common under such EGR operation and was able to simultaneously decrease NOx emissions and smoke emissions effectively. As an indicator, 20% cooled EGR registered a decrease of 9.2% and 12.3% in NOx emissions at 60% and 80% load, respectively, as compared with diesel operation and simultaneously reduced smoke emissions by 10% and 8.3% as compared with diesel operation.

An experimental study of performance and emission parameters of a compression ignition engine fueled by different blends of Diesel-Ethanol-biodiesel

The effects of different ethanol-diesel blended fuels on the performance and emissions of diesel engines have been evaluated experimentally and compared in this paper. After series of miscibility tests, it was found that ethanol is not miscible in diesel beyond 10% concentration. In order to increase its miscibility, Pongamia piñata methyl ester (PPME), popularly known as biodiesel was added as an amphiphilic agent. Different concentrations of ethanol and biodiesel produced different blends from which 4 blends were chosen for engine testing. The results indicated that biodiesel inclusion in the blends increased the brake thermal efficiency and reduced the fuel consumption of the engine. The study of emission parameters also showed that diesel ethanol blends reduced NOx and CO2 emission but increased hydrocarbon emission with elevated exhaust smoke opacity. It was also noticed that biodiesel inclusion in the blends reduced hydrocarbon emission, reduced exhaust smoke opacity with the penalties of simultaneous increase in NOx and CO2 emission.

Response Surface Methodology Based Multi-objective Optimization of the Performance-Emission Profile of a CI Engine Running on Ethanol in Blends with Diesel

The present study is aimed at optimizing the effect of ethanol-diesel blends on the performance and emission characteristics of a single cylinder (indirect injection) four-stroke diesel engine at different loads. Hexane was used as a co-solvent for higher ethanol concentration while Diethyl ether (DEE) was added as an ignition improver. D-optimal was chosen as the Design of experiment methodology. Quadratic polynomial models were constructed for the desired emission-performance parameters based on experimental data through the Response Surface Methodology NOx, CO and HC were chosen as the emission output parameters while BSFC. Load and ethanol-hexane-DEE concentration in the diesel blend were chosen as the input parameters. Multi-objective optimization involving the objective of minimizing both the emission and BSFC simultaneously yielded an optimal input condition of 5% hexane and 15% DEE in blend with 40% ethanol and diesel at 95% full load operation with 15.3% absolute error in NOx, 17.1% in HC, 1.69% in CO and 3.4% in BSFC estimation with respect to actual experimental values at the calibrated test condition predicted through RSM model optimization.

Performance Emission Characterization of a LPG-Diesel Dual Fuel Operation: A Gene Expression Programming Approach

The envisaged work attempts to explore the inherent capability of LPG as a potent alternative fuel, in diesel dual fuel paradigms in order to address the omni-present BTE-NOx-SOOT trade-off perspectives of an existing diesel engine. Furthermore, considering the prohibitive costs of computational time of present day 3D CFD platforms in multi-objective calibration challenges in I.C. engine domains, a unique gene expression programming (GEP) model has been proposed, to act as a robust and computationally rational system identification tool (SIT) in the LPG-diesel dual fuel platform. For the developed model, load, LPG energy share and injection duration were the chosen input variables, whereas BSFCEQ, BTE, NOx, SOOT, and HC were the corresponding output responses. Subsequent to GEP modeling, it was revealed that developed GEP model was competent enough to map the experimental engine output parameters with higher and commendable ranges of accuracy. The obtained results of coefficient of correlation were in the ranges of 0.99262–0.99769, while the error metrics of mean absolute percentage error values were in the ranges of 1.03–3.08% and very low values root mean square errors, respectively.

Hydrogen fuelled agricultural diesel engine with electronically controlled timed manifold induction: an experimental approach

The important motivations for exploring alternative fuel resources are energy security, air pollution, and climate change; problems that are collectively calling into question the fundamental sustainability of the current energy system. Natural gas and bio fuels are seen as the most important short-term options for meeting these goals, whereas in the long run, a substantial contribution is expected to be delivered by hydrogen which would facilitate the transition from limited non-renewable stocks of fossil fuels to unlimited flows of renewable sources. Hydrogen-fuelled internal combustion engines with near-zero emissions and efficiencies exceeding todays port-fuel-injected (PFI) engines are a potential near-term option and a bridge to hydrogen fuel cell vehicles where fuel cell undergoes development to make it economically viable. The unique combustion properties of hydrogen make it an ideal choice for its use in compression ignition engines. The present work attempts to explore the performance and emission characteristics of an existing single cylinder four-stroke compression ignition engine operated in dual fuel mode with hydrogen as an alternative fuel. The hydrogen was premixed with the incoming air and inducted during the duration of intake valve opening by an indigenously developed electro-mechanical means of solenoid actuation The performance and emission characteristics with hydrogen–diesel blend and neat diesel are compared. In this experiment hydrogen flow rate was kept constant at 0.15 kg/hr. The brake thermal efficiency with hydrogen–diesel blend is about 15.7% greater than that of neat diesel operation at 40% rated load. CO, CO2, HC and smoke emissions were significantly less with hydrogen–diesel blend. Smoke level was 41.6% lower than that of neat diesel operation at 80% load, whereas emission of CO2, CO, and HC levels were lower by 40.5%, 44.3% and 53.2% respectively for hydrogen enrichment at 80% load. In our present work EGR technique was examined in reducing NOx concentration. The NOx level decreased from 1211 ppm to 710 for hydrogen enrichment (0.15kg/hr) at 80% of the rated load.