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As fossil fuel resources are considered non-renewable sources of fuel, they will be totally consumed in the near or far future. Due to the intensive and extensive consumption of these fossil fuels in all life sectors such as transportation, power generation, industrial processes, and residential consumption, it is important to find other new methods to cover this fuel demand. Fuel additives are chemicals used to enhance fuel combustion performance, save fuel amounts required for combustion, and correct deficiencies in power and efficiency during consumption. The fuel additives are blended with the traditional fuel even by parts per million range for controlling chemical contaminants and emission reduction. In the present work, the experimental measurements were done, to evaluate the effect of fuel additive blending with the raw heavy fuel oil (Mazut) on fuel saving which is of a great significance, emissions control, and combustion characteristics as well as the combustion efficiency. These measurements are as follows: initial temperature of Mazut, exhaust gas temperature at the end of combustor, air and fuel mass flow rates to determine the heat load, inlet and outlet temperatures of cooling water, mass flow rate of water, concentration of different exhaust gases, acoustic (noise level) measurements, smoke number, and flame length. These measurements are performed using swirled vanes, co-axial, and double heavy fuel nozzle (1.5 gal/hr for each one) burner with maximum heating load of 550 kW. GC-MS (Gas chromatography-mass spectrometry) analysis was performed by using Hewlett Packard model 5890 equipped with a flame ionization detector (FID) to identify the fuel additives substances within the tested samples. The results reveal that the use of fuel additives improves the combustion characteristics and play an important role in fuel saving as well as emission and combustion process.

A turbocharger is certainly one of the fundamental devices being employed to enhance output power of petrol and/or diesel and is of paramount importance for use in heavy duty diesel engines.This work aims to increase the power of a six-cylinder turbocharged, four stroke, direct injection heavy duty diesel engine via replacing its fitted turbocharger with a properly selected and matched one. The matching criteria and the effect of intercooler presence are studied. A performance prediction model for turbocharged engine is created to investigate the engine-turbocharger matching. To address this, a program code has been upgraded and modified to select the suitable engine turbocharger using FORTRAN PowerStation 5.0 language. The study includes also an experimental part; where three types of turbochargers, (namely HX80, HB3 and HX40) are tested. The P-Ф diagram, the engine performance parameters together with the exhaust and soot emissions are measured and compared for the cases of original and best turbocharger (HX80). The developed computer algorithm appears to provide results that are in good agreement, within acurcey of + 5%, with the measured data; a fact that encourages designers to trustly use it in their selection and matching of a turbocharger to diesel engines.

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The swirling flow velocity profiles can be strongly influenced by the outlet conditions of the combustion chamber especially at subcritical flow conditions. The effect of such changes on the mean flow or coherent structures is still unclear. It is investigated in the present work in an industrial swirl inducing burner in cold flow conditions with help of PIV. Proper orthogonal decomposition (POD) as well as acoustic measurements were used to characterize the coherent structures shed from the burner mouth. The combustor length (670, and 2020mm) and the outlet area contraction ratio (1, 0.56, 0.27, and 0.09) are varied. Major changes in the flow field are achieved when using a short combustor and the smallest contraction ratio. For this case, a central jet with streamwise velocity is added to the typical central recirculation zone. The POD analysis of the contraction ratios 1 and 0.09 for the long combustor shows that the first helical mode as well as Kelvin Helmholtz vortices are present with minor changes for both cases. At a contraction ratio of 0.09, some new structures at the jet location and near the combustor wall appear.

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