الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Effect of direct injection of water and steam, on NOx reduction from the gaseous fuel (LPG) is investigated experimentally including different parameters, as following:
1- Gas fuel supply flowrate.
2- Water and steam injection flowrate.
3- Injection location (Primary, Secondary and Tertiary)
4- different injection angles 30, 45, 90 and 135 degree in a radial direction towards the combustor axis considering each angle injected individually and see its effect on NOx reduction values.
On the other hand; Theoretical calculation have been performed to validate the adiabatic flame temperature that directly affect the NOx concentration values; then from the experimental results it can be concluded;
i- Exhaust gas temperature is directly affected by the adiabatic flame temperature.
ii- (LPG) fuel flowrate is one of the main factors on NOx formation values whether increased or decreased.
iii- The injection of both water and steam reduce the flame temperature, which reduce the possibility of NOx formation.
iv- Water injection is more effective than steam injection in reducing NOx concentration, because water needs more heat to evaporate, which leads to reduce the combustion (flame) temperature, so reduce the possibility of NOx formation.
v- The best injection water to fuel (W/F) ratio is (0.4), and for steam to fuel (S/F) ratio is (0.35) under the current operating conditions in this study, which reduce flame temperature, and exhaust temperature, so, reduce the possibility of NOx formation.
vi- Water and steam injection are an effective methods to reduce NOx under the operating current parameters, flame tempeature decrease leads to reduce 70% of NOx concentration with using of water injection, 57% NOx reduction with steam injection method compared with the current values, without injection of water or steam.
vii- Injection location has another major effect on the NOx reduction, as the best injected location is the primary holes (firing zone) compared with the secondary and tertiary holes, because this is the reactions zone in which the combustion reactions have been taking place.
viii- The best angle is at (45) in a radial direction, due to better water and steam distribution at this degree which benefits from the water or steam flow effectively inside the hot region then utilizing it without scattering to the combustor liner wall and lose the flow , then resulted the least flame temperature and accordingly the better NOx concentration reduction.
Based on the above, it can be concluded that water injection is the best effective method used in reducing the possibility of NOx formation, taken into consideration the injection location in primary (firing) zone and the tilt injection angle of (45) in radial position, with water to fuel ratio at (0.4), and steam to fuel (S/F)ratio at (0.35); also NOx concentration values are proprtionally effect with LPG fuel flowrate and flame temperature.