The process of atomization is one in which a liquid jet or sheet is disintegrated by the kinetic energy of the liquid itself, or by exposure to high velocity air or gas, or as a result of mechanical energy applied externally. Combustion of liquid fuels in engines and industrial furnaces is dependent on effective atomization to increase the specific surface area of the fuel and thereby achieve high rate of mixing and evaporation. The pressure swirl atomizer is most common type atomizer used for combustion in gas turbine engines and industrial furnaces. The spray penetration is of prime importance for combustion designs. Over penetration of the spray leads to impingement of the fuel on walls of furnaces and combustors. On the other hand, if spray penetration is inadequate, fuel–air mixing is unsatisfactory. Optimum engine performance is obtained when the spray penetration is matched to the size and geometry of combustors. Methods for calculating penetration are therefore essential to sound engine design. Equally important are the spray cone angles and the drop size distribution in the sprays. An attempt is being made to experimentally investigate pressure swirl atomizer performance parameters such as spray cone angle, penetration length and drop size at different injection pressures ranging from 6 bar to 18 bar.

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The challenges in designing high performance combustion systems have not changed significantly over the years, but the approach has shifted towards a more sophisticated analysis process. A technical discussion on combustion technology status and needs will show that the classic impediments that have hampered progress towards near stoichiometric combustion still exist. Temperature rise, mixing, liner cooling, stability, fuel effects, temperature profile control and emissions continue to confront the aerodynamic and mechanical designers with a plethora of engineering dilemmas and trade-offs. The process of combustion chamber design has taken a new meaning over the past several years as three dimensional codes and other advanced design and validation tools have finally changed the approach from a "cut and burn" technique to a much more analytical process. All of these new aspects are now integral elements of the new equation for advanced combustor design that must be fully understood and utilized. Only then will the operable, high temperature capable or low emission combustor systems needed for future military and civil aircraft as well as for stationary gas turbines can be developed. The present paper is an attempt to analyze the flow patterns within the combustion chamber of a 20 kW gas turbine engine using a CFD code CFX. It summarize the CFD simulation of the complete combustion chamber including primary zone, intermediate zone and dilution zone and finally attempts to achieve temperature distribution in the entire combustion chamber. These CFD results are then compared with experimental readings which not only validates analytical results but leads towards improved design.

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