نوع مقاله : علمی پژوهشی

نویسندگان

1 گروه مهندسی هوافضا، دانشکده فنی و مهندسی، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران

2 استادیار، گروه مهندسی هوافضا، دانشکده فنی و مهندسی، دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران، ایران

10.22034.jtae.2024.8.3.4

چکیده

هدف این پژوهش شناسایی الگوی جریان در شرایط خارج از طراحی یک توربین محوری پرفشار خاص است. با نوشتن کد طراحی مقدماتی، توربین محوری پرفشار طراحی و سپس هندسه این توربین در نرم‌افزارهای کتیا و انسیس دیزاین مدلر تولید شد. سپس هندسه در نرم‌افزار توربوگرید شبکه‌بندی شده و با استفاده از نرم افزار انسیس سی اف ایکس در 12 نقطه‌ی خارج از طراحی مورد بررسی و تحلیل قرار گرفت. ابتدا با نسبت سرعت روتور ثابت، نسبت فشار سکون ورودی تغییر کرد. سپس با نسبت فشار سکون ورودی ثابت، نسبت سرعت روتور تغییر کرد. با افزایش نسبت فشار سکون ورودی، مشاهده شد که عدد ماخ جریان به بالای یک رسید و راندمان توربین به مقدار قابل توجهی افت پیدا کرد. کاهش نسبت فشار سکون ورودی تا یک حد مشخصی باعت بهبود عملکرد توربین شد؛ اما با افت بیشتر نسبت فشار سکون ورودی، راندمان توربین سیر نزولی پیدا کرد. با توجه به بررسی الگوی جریان و پارامترهای عملکردی، شرایط کاری‌ در نسبت فشار سکون ورودی 0.9 در مقایسه با سایر نقاط کاری بهتر بوده و راندمان توربین به عدد 0.93می‌رسد. با تغییرات نسبت سرعت روتور، نواحی مستعد جدایش جریان در اطراف پره‌های توربین به ویژه در سطح مکش پره‌های روتور افزایش داشت.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Analysis and identification of the flow pattern in a specific high-pressure axial turbine in off-design conditions

نویسندگان [English]

  • Sahar Saharkhiz 1
  • Reza Aghaei Togh 2

1 Department of Aerospace Engineering, Faculty of Engineering, Islamic Azad University Science and Research Branch, Tehran, Iran

2 Assistant Professor, Department of Aerospace Engineering, Faculty of Engineering, Islamic Azad University Science and Research Branch, Tehran, Iran

چکیده [English]

The aim of this research is to identify the flow pattern in off-design conditions of a specific high-pressure axial turbine. by writing the preliminary design code, the turbine was designed, Then the geometry of this turbine was designed in CATIA and Ansys Design Modeler softwares, and it is meshed in Turbogrid software. the turbine is analyzed using the Ansys CFX software at 12 points in off-design conditions. with fixed rotor speed ratio, inlet static pressure ratio was changed. Then with fixed inlet static pressure ratio, the rotor speed ratio was changed. With the increase of the inlet static pressure ratio, the Mach number of the flow reached above one and the turbine efficiency dropped significantly. Reducing the inlet static pressure ratio to a certain extent improved the performance of the turbine; But with a further drop in the inlet static pressure ratio, the turbine efficiency began to decline. the working conditions at the inlet static pressure ratio of 0.9 are better compared to other working points and the turbine efficiency reaches 0.93. With changes in the rotor speed ratio, the areas prone to flow separation around the turbine blades increased, especially on the suction surface of the rotor blades.

کلیدواژه‌ها [English]

  • High-pressure axial turbine
  • off-design conditions
  • rotor speed ratio
  • inlet static pressure ratio
  • flow separation
  • turbine efficiency
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