کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4916130 1428086 2017 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Numerical analysis of deposit effect on nozzle flow and spray characteristics of GDI injectors
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی مهندسی انرژی و فناوری های برق
پیش نمایش صفحه اول مقاله
Numerical analysis of deposit effect on nozzle flow and spray characteristics of GDI injectors
چکیده انگلیسی
Injector deposit is a common phenomenon for gasoline direct ignition (GDI) engines that greatly affects the spray behavior and consequently the combustion performance and emissions. In this study, the effect of deposit on both the in-nozzle flow dynamics and downstream spray behaviors was numerically investigated. High-resolution X-ray microtomographic scans were performed first to obtain nozzle and deposit morphologies and topology. In-nozzle simulation was then carried out in the Euler-Euler framework with cavitation taken into account by a homogeneous relaxation model (HRM). Finally, the effect of deposit on spray behaviors was evaluated in the Euler-Lagrangian framework, coupled with the in-nozzle simulation results. Results of the nozzle flow simulations highlight that the rough surface of the deposits leads to additional cavitation inception and restricts the flow area, causing mass flow rate losses. Deposits inside the counterbore act as an extension to the inner orifice and constrain the air recirculation. Turbulent levels at the exit of the counterbore are lower for the coked injector due to the reduced air/fuel interaction. Spray simulations have shown that deposits would lead to longer spray penetration, a smaller spray cone angle and larger droplets diameters. Simulation results agree reasonably well with the available experimental data.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Energy - Volume 204, 15 October 2017, Pages 1215-1224
نویسندگان
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