بکارگیری ضریب همگنی جهت ارزیابی تاثیرات مشخصه های پیش پاشش سوخت بر کیفیت فرآیند اختلاط سوخت و هوا و نحوه عملکرد یک موتور اشتعال تراکمی پاشش مستقیم سرعت بالا پرخوران

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشگاه حضرت آیت الله العظمی بروجردی (ره)

چکیده

تاثیرات همزمان میزان سوخت پیش‌پاشش و زمان‌بندی پیش‌پاشش بر فرآیند اختلاط سوخت و هوا، عملکرد موتور و مقدار آلاینده‌های تولیدی در یک موتور اشتعال تراکمی پاشش مستقیم سرعت بالای پرخوران بررسی شده است. برای این منظور از پارامتر اصلاح شده‌ای با نام «ضریب همگنی» به عنوان معیاری جدید در ارزیابی کیفیت فرآیند اختلاط سوخت و هوا بهره برده شده است. ابتدا نتایج حاصل از شبیه سازی با داده های تجربی مورد مقایسه قرار گرفته است و تطابق مناسبی جهت پیش‌بینی مقادیر فشار داخل سیلندر، میزان حرارت آزاد شده و مقادیر آلاینده‌های تولیدی حاصل شده است. نتایج این تحقیق نشان می‌دهد، مقدار سوخت پیش‌پاشش تاثیرات به مراتب بیشتری بر کیفیت اختلاط سوخت و هوا در مقایسه با زمانبندی پیش پاشش سوخت دارد به نحوی که با جلوانداختن زمان پیش پاشش سوخت، بیشینه مقدار «ضریب همگنی» در زمانی سریعتر حاصل گردیده و مدت زمان بیشتری برای ایجاد مخلوطی همگن‌تر جهت اشتعال فراهم خواهد شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Applying the Homogeneity Factor to Evaluate the Effects of Pilot Injection Characteristics on Air-Fuel Mixing Quality and Engine Performance in a Turbo-Charged High Speed Direct Injection (HSDI) Diesel Engine

نویسندگان [English]

  • Raouf Mobasheri
  • Mahdi Seddiq
University of Ayatollah ozma Boroujerdi
چکیده [English]

In current research, the simultaneous effects of pilot fuel quantity and pilot injection timing on air-fuel mixing process, engine performance and the amount of pollutant emissions have been investigated in a High Speed Direct Injection (HSDI) turbo-charged diesel engine. For this purpose, a modified parameter called “Homogeneity Factor (HF)” has been applied as a new measure for analyzing the air-fuel mixing process. The simulated results has been firstly compared with the experimental data and a very good agreement has been achieved for simulating the in-cylinder pressure, the heat release rate and the amount of pollutant emissions. The results show that the pilot fuel quantity is more effective on air-fuel mixing quality than pilot injection timing. By advancing the start of pilot injection timing, the maximum amount of Homogeneity Factor (HF) during pilot injection, is achieved at an earlier time. As a result, for earlier SOP timing, a sufficient mixing is available to achieve a more homogeneous at the time of ignition.

کلیدواژه‌ها [English]

  • Diesel engine
  • Homogeneity Factor
  • Pilot Injection
  • Engine Performance
  • Pollutant Emission
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