Effects of Nozzle Diameter on the Spray Characteristics of Premix Injector in Burner System

Abstract

An essential component of the injector nozzle geometry is to see the results spray atomization and mixture formation of the fuel-air combustion to improve performance, and reduce pollution from a burner. Studies involving the injectors in the combustion burner are still in a small proportion, particularly in the premix injector type. Thus, this study involves the efforts to determine the appropriate diameter of the premix injector where the injector spray characteristics is produced by using Computational Fluid Dynamics (CFD). Multiphase of the volume of fluid (VOF) cavitations flow in the nozzle is determined through steady simulation while Eulerian-Eulerian two-fluid approach is used for performing mixing of Jatropha oil and air. Further simulation is conducted using a spray with a discrete phase injection at the outflow hole injector nozzle. The investigation involves the modification of nozzle geometry on three different sizes of 0.8 mm, 1.0 mm and 1.5 mm with the analysis focused on nozzle flow characteristics of the injector. The results indicate that a small changes in injector gives high impact to the spray and combustion of a burner. This shows the importance of nozzle dimensions which influences the nozzle flow and affects the spray characteristics, hence influence the combustion and emission of the burner system.