Large Eddy Simulation of GDI Single-hole and Multi-hole Injector Sprays with Comparison of Numerical Break-up Models and Coefficients

• Main Authors: hamed zamani, vahid hosseini, Hossein Afshin, Luigi Allocca, Mahdi Baloo
• Format: Article
• Language: English
• Published: Isfahan University of Technology 2016-01-01
• Series: Journal of Applied Fluid Mechanics
• Subjects: Gasoline Direct Injection (GDI) engine; single-hole and multi-hole spray; spray tip penetration; Large Eddy Simulation
• Online Access: http://jafmonline.net/JournalArchive/download?file_ID=39426&issue_ID=225

In the present study the fuel spray of a gasoline direct injected engine with multi-hole injector is simulated. Simulation inputs data, injection flow rate and spray cone angle are obtained from previous experimental studies. Log-normal distribution with different standard deviation is used for initial droplet size as the primary break-up model in order to reach the agreement between experimental and calculated spray tip penetration. As the first step, only one plume of spray injected into a quiescent air environment is simulated and validated by varying break-up model and standard deviation. Then, with coefficient obtained from the single jet simulation all six spray jets are simulated based on the injector nozzles geometry. The comparison between single-jet simulation and multi-jet simulation shows that validated model coefficients for the single-jet spray cannot be used for multi-jet spray simulation without significant modifications due to adjacent jet interaction and pressure drag. A set of new coefficients for the multi-jet spray is presented