Accelerating Design of Complex Fuel Injectors Through Petascale Computing

Project Description

A critical sub-component of a liquid fueled combustor is the fuel injector. Liquid spray breakup from complex fuel injectors is a poorly understood phenomenon, except perhaps in canonical configurations [1], yet it has a significant influence on the engine performance in terms of emissions, fuel consumption, thermo-acoustic instabilities and durability [2]. Analytical studies in canonical configurations have largely focused on linear and non-linear stability analyses to provide insights into the mean drop sizes that result from liquid spray breakup [3, 4]. The origin of several physical sub models for sprays from complex injectors that are widely employed in numerical calculations of liquid-fueled combusts can be traced back to such analytical techniques. A primary drawback of such analytical techniques is their inability to predict the non-linear unsteady behavior of the spray. Unsteadiness in the liquid spray and surrounding atomizing air can result in a multitude of length and time scales associated with the liquid spray breakup phenomenon. Turbulence in the atomizing air or in the liquid has a significant influence on the drop size distribution after liquid breakup [5], and this introduces an additional layer of uncertainty in the applicability of analytical techniques to complex fuel injectors.