Identification of cross-flow liquid-jet structures by means of statistical image evaluation

The aim of this paper is to study how the morphology of a liquid jet in cross-flow conditions can be influenced by characteristic parameters of atomization. The technological reference of this work are the LPP (Lean Premixed Prevaporized) gas turbine systems. In these systems the combustion process occurs in premixed conditions with a very high air excess in order to avoid NOx forming. The operation of such systems with liquid fuels require a particular care in the preparation of the fuel-air mixture. Fuel injection in an air cross-flow is commonly used to favour a prompt and good mix of air and fuel. This technique presents two main disadvantages: the impact of the liquid jet against the wall; Flashback phenomenon occurring when flame propagation is faster than air velocity allowing for fuel ignition in the inlet duct. To avoid these two disadvantages, the atomization system and the complex coupling between fuel and air streams require particular care in system design. This paper contribute to the general understanding of jet dispersion and its interaction with air flow and attempt to determine a semi-empirical correlation useful to predict liquid jet trajectory in cross-flow conditions.