A Study on Alternate Fuel Spray Parameters and Their Impact on Combustion Performance and Emissions

Abstract

This research investigates the influence of various methods aimed at improving the spray characteristics of waste cooking oil biodiesel on combustion performance and emissions. Utilizing an Eulerian-Lagrangian approach, with a particular focus on multiphase flow and linearized instability, this study employs the Taylor analogy break-up model and the sheet atomization model to assess atomization, film formation, and sheet breakup. Additionally, spray tip penetration validation is conducted to evaluate the model's robustness. Notably, a lower sensitivity of the spray cone angle to injection pressure is observed. In the context of swirl nozzles, the spray angle is determined by various factors, including liquid surface tension, ambient pressure and temperature, nozzle aperture length, and orifice diameter. Due to increased energy dissipation, fuel jets in swirl nozzles exhibit accelerated disintegration, rendering them more responsive to changes in injection pressure. Remarkably, soot production from swirl atomizers was consistently lower across all injection pressures, attributable to the enhanced secondary atomization achieved by swirl nozzles, particularly at higher injection pressures. Importantly, the reduced impact of centrifugal forces in swirl injectors results in a smaller discrepancy in soot production between swirl and traditional nozzles at lower injection pressures