الفهرس 
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Abstract
The objective of this work is to identify the most influencing parameters to the flame less combustion systems. Ten influencing parameters were identified for consideration in the design and experimentation efforts of flameless combustion systems. These parameters were listed and the interplay between them was discussed. Also, this work concludes with an attempt to reproduce the laboratory measurements of the flameless ”FOUR” combustion facility (proposed by C. Rottier). To achieve these goals, the different experimental findings of other researchers will be thoroughly reviewed in order to develop a deeper understanding of the flameless phenomena. This review is concluded by revealing the influencing parameters and emphasizing the need for an accurate numerical modelling of the flameless combustion. Significant discrepancies are noted between the experimental measurements and the numerical results from multiple research campaigns. A concise discussion is presented on the available literature on the subject of numerical modelling for the FC mode. Eventually, seven different modelling setups are selected and their potency is investigated in regards to reproducing the measurements from aforementioned ”FOUR” facility. These numerical investigations were conducted using the ANSYS FLUENr® software. The use of two turbulence models was explored (standard and modified k-s), along with two kinetic mechanisms (a globaI2-step, and the detailed KEE-58), and three Turbulence/Chemistry Interaction (TCI) models; Finite-Rate/Eddy-Dissipation (FRIED), Eddy Dissipation Model (EDM), and the Eddy Dissipation Concept (EDC) with modified global constants. The results of these modelling setups are discussed and assessed based on the quality of their predictions of the following aspects; the temperature field and the maximum temperature, exhaust NOx level, the onset of premature ignition, and reactants entrainment ratio. The selected modelling setups graduate in their complexity. The most agreeable representation of the experimental measurements, of two reference test cases, is achieved with only two setups. These two setups employed the following: Modified k-e (MKE) - The detailed kinetic mechanism KEE- 58 - The Eddy Dissipation Concept (EDC) for TCI with modified constants. One model had the time scale constant Cl of the EDC increased to 1.5 from the default value of 0.4083. This model was able to adequately capture the temperature field and the exhaust NOx, but it largely overestimated the reactants entrainment ratio by - 65%. The other setup had the volume fraction constant C, reduced to 1.0. Only one of these two setups has achieved the most acceptable qualitative agreement with the ”FOUR” facility measurements. The most accurate model setup employed the following: MKE - KEE-58 - EDC with a reduced C, (from 2.1377 to only 1.0). It provided a very accurate reproduction of the reactants entrainment ratio in the mixing zone and delivered the most agreeable prediction of the temperature field and exhaust NOx emission.