Formulas of reducing engine environmental performance and combustion characteristics to standard atmospheric conditions

The article specifies formulas of reducing environmental performance and combustion characteristics of a gas turbine engine, as well as its thermodynamic parameters to the standard atmospheric conditions, with flight altitude H = 0 and Mach number M = 0: p₀= 760 mm Hg. (101.325 kPa), T₀=288.15 K (+15°C), for which the engine technical assignment is specified. The atmospheric conditions determined by the air temperature, pressure and humidity vary over a wide range depending on the season, terrain elevation, and latitude. Therefore, reduction of engine characteristics to the standard atmospheric conditions is necessary and it is based on the similarity theory, i.e. on maintaining constant gas dynamic and geometrical criteria of the combustion chamber. An integral mathematical model of the combustion chamber forms the theoretical basis of the presented reduction method. It is grounded on the results of solving a system of differential equations describing heat, mass (concentration) and momentum transfer specified by the combustion chamber theory. The article shows a significant influence of the ambient air temperature on emission and fuel combustion characteristics as distinct from the influence of other atmospheric parameters.