Experimental and CFD analysis of Re-entrant Combustion Chamber on Diesel Enriched with Hydrogen

In view of global warming and diminution of sources for traditional fuels, investigators paid their attention towards finding the substitutes in all sectors such as agriculture, transportation and industries. One of the best alternative and unique option for overcoming these limitations is usage of hydrogen gas as fuel for petroleum-based engines. Further to have better quality of fuel and air mixture formation, a significant part is played by the geometry of the combustion chamber. To have quality burning of the fuel, an effort is targeted to investigate the impact of re-entrant chambers over the conventional type without and with hydrogen enrichment at distinct flows of diesel. Initially, experiments were conducted on toroidal chamber geometry of the piston bowl with diesel and with hydrogen enrichment. With a reduction of 30.65%, 44.11% and 18.78% in emission particulates of UHC, CO and smoke density correspondingly with addition of hydrogen as that of with diesel at peak load, further there is growth in NOx emissions about 10.16%. The variations of emission particulates with replacement of modified geometry, i.e. re-entrant type are detected as further reduced. To validate the reduction in emission trends, CFD simulations are carried out on fuel mass fraction and the findings presented.