Effects of Thermodynamic Conditions and Nozzle Geometry on the Methane Direct Injection Process in Internal Combustion Engines
2022-01-0606
03/29/2022
- Event
- Content
- It's known direct injection of gaseous methane can involve the presence of under-expanded jets. Understanding the physics of such process is imperative for developing Direct Injection (DI) internal combustion engines fueled indeed by gaseous fuels. The paper presents an experimental-numerical characterization of the spray issued from an innovative multi-hole injector designed for application in heavy-duty engines. The experimental characterization of the jet evolution was recorded by means of schlieren imaging technique and then, using such measurements for the validation, a numerical simulation procedure was assessed. A high-order and density-based solver, capable of reproducing the most relevant features of the under-expanded jets, was developed within OpenFOAM framework. Both early and late injection configurations were investigated. They lead, during the engine cycle, to completely different upstream-to-downstream pressure ratios and so two representative Net Pressure Ratios (NPR) were studied. Then, the attention was focused on the effects of the nozzle geometry and consequentially on the mixture formation process. The simulations performed, allowing a comprehensive characterization of the turbulent and transonic flow, demonstrated how this latter parameter strongly affects the quality of the air/fuel mixture and, generally, the global performances of the injection process.
- Citation
- Duronio, F., Montanaro, A., Allocca, L., Ranieri, S. et al., "Effects of Thermodynamic Conditions and Nozzle Geometry on the Methane Direct Injection Process in Internal Combustion Engines," SAE Technical Paper 2022-01-0606, 2022, .