بررسی تجربی و عددی هیدرودینامیک انژکتور مارپیچی و ارائة پارامترهای حل سازگار با مشخصات اسپری

نوع مقاله: مقاله پژوهشی

نویسندگان

1 عضو هیات علمی / دانشکدة علوم و فنون نوین، دانشگاه تهران

2 دانشجوی کارشناسی ارشد / دانشکدة علوم و فنون نوین، دانشگاه تهران

چکیده

استفاده از انژکتورهای مارپیچی از جمله روش‌های متداول و مناسب در اسپری مایعات است. در این مقاله، نخست عملکرد این نوع انژکتورهای تک‌پایه به‌روش تجربی مورد بررسی قرار گرفته است. سپس، اثر دو پارامتر هندسی مهم در این انژکتورها؛ یعنی قطر اوریفیس خروجی و زاویة مارپیچ، به‌عنوان کمیت‌هایی که اثر غالب دارند، بررسی ‌شده است. نتایج تجربی نشان می‌دهد که کاهش زاویة مارپیچ و افزایش قطر اوریفیس خروجی، قطر میانگین ساوتر قطرات را افزایش می‌دهند. در ادامه، شبیه‌سازی عددی اسپری انژکتور پیچشی با استفاده از نرم‌افزار متن‌باز اوپن‌فوم در دو تست مختلف انجام و پارامترهای ضریب شکست اولیه و پارامتر توزیع در مدل عددی به‌صورتی سازگار با نتایج تجربی و در محدودة فشاری پایین ارائه شده است. نتایج عددی نشان می‌دهد که انتخاب مقادیر 5 و 3 برای ضریب شکست اولیه و همین‌طور مقادیر 3 و 2/3 برای پارامتر توزیع به‌ترتیب در تست‌های اول و دوم، سرعت و توزیع اندازة قطرات حاصل از اسپری را با دقت خوبی پیش‌بینی می‌کند. با استفاده از ثابت‌های به‌دست‌آمده می‌توان اسپری مخروطی توخالی انژکتورهای مارپیچی در محدودة فشاری پایین (پایین‌تر از 15 بار) را از این ‌پس مستقل از نتایج تجربی مدلسازی کرد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental and numerical investigation on hydrodynamic of spiral atomizer and presenting of compatible solution parameters with spray characteristics

نویسندگان [English]

  • Maziyar Shafaee 1
  • Saeed Fazlikhani 2
2 M.Sc. Student/ Factuly of New Sciences and Tecnologies/ University of Tehran
چکیده [English]

The use of spiral atomizers is one of the common and appropriate methods to produce liquid sprays. In this paper, we have investigated the performance of these single-base atomizers experimentally. Then, the effects of two important geometrical parameters in these type of atomizers, orifice diameter and spiral angle as quantities that have dominant effects were studied. After this, the numerical simulation of spray was conducted using the open-source OpenFOAM code and helping of experimental results, parameters in numerical models compatible with these results are presented in the low pressure range. Experimental results show that decreasing spiral angle and output orifice diameter, increases Sauter mean diameter of droplets. In addition, the numerical simulation of spiral atomizer predicts velocity and size distribution of spray droplets with good accuracy that shows validity of the experimental parameters used in numerical models. In this paper using experimental results, numerical model parameters that are compatible with hollow cone spray of these atomizers have presented that with the presented parameters, Hereinafter simulation of hollow cone spray in pressure range of this paper could be done independent of the experimental results.

کلیدواژه‌ها [English]

  • low-pressure spray
  • spiral atomizer
  • PDA system
  • Sauter means diameter
  • OpenFOAM

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