مطالعه افشانه موتور تزریق مستقیم در محفظه حجم ثابت با اندازه‌گیری نوری و شبیه‌سازی دینامیک سیالات محاسباتی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 شرکت تحقیق، طراحی و تولید موتور ایران خودرو، تهران، ایران

2 عضو هیات علمی دانشکده مهندسی مکانیک دانشگاه تربیت دبیر شهید رجایی

چکیده

عملکرد بهتر و الزامات نظارتی با توجه به انتشار احتراق باعث کوچک شدن موتور تزریق مستقیم و در نظر گرفتن راهبردهایی برای بهبود آماده ‏سازی مخلوط درون استوانه شده است. ویژگی‏ های فواره افشانه ‏های سوخت موتورهای تزریق مستقیم به طور گسترده توسط محققان بررسی شده است. علاقه به مطالعه ویژگی ‏های فواره‏ ها به دلیل رابطه مؤثر با واکنش احتراق و در نتیجه با بازده گرمایی موتور است. این مقاله تشکیل مخلوط فواره را با استفاده از یک دستگاه آزمایشی لیزری مورد استفاده برای اندازه‌گیری نفوذ فواره در محفظه حجم ثابت و شبیه‌سازی‌های انجام شده توسط نرم‌افزار کانورج با پاسخ سریع تحلیل می‌کند. افشانه سوخت مورد استفاده در آزمایش یک افشانه تزریق مستقیم شش سوراخی با سوخت ایزواکتان بود. اندازه‏گیری‏ ها در 100 میلی‏متر پایین دست از نوک افشانه‏ در امتداد محور با فشار تزریق 20 مگاپاسکال انجام شد. در طول آزمایش ‏ها، مشاهده شد که توسعه فواره با محور عمودی قرینه نیست، و با کاهش فشار محفظه، سرعت توسعه آن افزایش می‌یابد. همچنین میانگین سرعت‏های توسعه فواره در شبیه‌سازی‏ ها با نتایج تجربی مشابه یکدیگر اند. 

کلیدواژه‌ها


عنوان مقاله [English]

Study of GDI injector in constant volume chamber by optical measurements and CFD-Simulation

نویسندگان [English]

  • Ali Asef 1
  • Arash Mohammadi 2
  • Vahid Khorramirad 1
  • Nima Ajami 1
  • Amir Hossein Parivar 1
  • Karim Maghsoudi Mehraban 2
1 Irankhodro Powertrain Company (IPCO), Tehran, Iran
2 Faculty of Mechanical Engineering Department, Shahid Rajaee Teacher Training University
چکیده [English]

Better performance and the regulatory requirements concerning combustion emissions have caused downsized GDI engines and consideration of strategies for improving in-cylinder mixture preparation. The sprays characteristics of the fuel injectors of GDI engines have been widely investigated by researchers. The interest in studying the characteristics of the spray is due to a strong relationship with the subsequent combustion reaction and thus with the engine's thermal efficiency. This paper analyzes the mixture formation of the spray employing an experimental laser apparatus that was used to measure the spray penetration in a constant volume chamber (CVC) and simulations performed by the fast response CFD CONVERGE software. The fuel injector used in the tests was a six-hole direct injection injector with iso-octane fuel. The measurements were taken 100 mm downstream from the injector tip along the axis with 20 MPa injection pressure. During experiments, it was observed that spray development is not symmetrical with the vertical axis, and with decreasing chamber pressure, it develops faster. Moreover, the average spray development velocities in simulations are in good agreement with experimental results.

کلیدواژه‌ها [English]

  • GDI
  • Injector
  • Optical
  • CFD
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