تحقیق تجربی و عددی ضریب اثربخشی خنک‌کاری لایه‌ای در نوک پره توربین دارای اسکوئیلر

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه علم و صنعت

2 دانشکده مکانیک / دانشگاه علم و صنعت / تهران / ایران.

3 دانشکده مهندسی مکانیک / دانشگاه علم و صنعت ایران / تهران / ایران

چکیده

در کار تحقیقاتی حاضر، به بررسی اثر حضور اسکوئیلر در بهبود عملکرد آیرودینامیکی و توزیع بار حرارتی در ناحیه نوک پره پرداخته شده است. ابتدا اثر چهار نسبت دمش مختلف بر روی عملکرد خنک‌کاری نوک پره دارای اسکوئیلر به‌صورت تجربی و با استفاده از روش اندازه‌گیری انتقال حرارت در حالت پایا بررسی شده است. سپس با بهره‌گیری از رهیافت معادلات ناویر-استوکس به روش میانگین‌گیری رینولدز به بررسی عملکرد خنک‌کاری و افت‌های آیرودینامیکی در نوک پره تخت و دارای اسکوئیلر پرداخته شده است. نتایج حاصل از تحقیقات تجربی نشان می‌دهد در پره دارای اسکوئیلر، با افزایش نسبت دمش، مناطق وسیع‌تری از نوک پره تحت پوشش سیال خنک‌کننده قرار می‌گیرند. نتایج شبیه‌سازی عددی نشان می‌دهد، در تمام نسبت دمش‌ها، متوسط اثربخشی در سطح پروفیل پره با نوک تخت کمتر از پره دارای اسکوئیلر است. در پره دارای اسکوئیلر، با افزایش نسبت دمش، مقدار متوسط ضریب انتقال حرارت در سطح پروفیل پره‌ با نوک تخت و دارای اسکوئیلر به ترتیب به مقدار 43% و44% کاهش پیدا کرده و متوسط ضریب اثربخشی بر روی لبه داخلی اسکوئیلر و سطح بالای اسکوئیلر به ترتیب 23% و 15% افزایش پیدا می‌کند. ضمنا با بالا رفتن نسبت دمش، انتقال حرارت در سطوح ذکرشده کاهش پیدا می‌کند.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental and Numerical Investigation of Film Cooling Effectiveness on Squealer Tip of a Turbine Blade

نویسندگان [English]

  • Reza Taghavi Zenouz 1
  • Pantheia Peikani 2
  • Ali Akbarzadeh 3
1 School of Mechanical Engineering/ Iran University of Science and Technology/ Tehran / Iran
2 School of Mechanical engineering / Iran University of Science and Technology / Tehran / Iran
3 School of Mechanical Engineering / Iran University of Science and Technology / Tehran / Iran
چکیده [English]

In this article, the effects of squealer on aerodynamic performance and thermal load distribution on the blade tip region are investigated. Experimental results are presented at blowing ratios of 0.5, 0.75, 1.0, and 1.5. The film-cooling effectiveness is measured via the steady-state heat transfer measurement technique. A numerical approach has been applied to compare the film cooling performance and aerodynamic losses in the plane and recessed blade tips. The experimental results indicate that, as the blowing ratio increases, the coolant jets provide better cooling coverage on the cavity surface. The numerical results show that the plane tip film-cooling effectiveness is lower than that for the squealer tip. It can be observed that, for the plane and squealer tip configurations, as the blowing ratio increased, the heat transfer coefficient decreased by about 43% and 44%, respectively. Moreover, the film-cooling effectiveness on squealer tip surface and rim walls increased by 15% and 23%, respectively. Furthermore, the lower heat transfer coefficient was observed at a higher blowing ratio on the surfaces mentioned above. The squealer tip geometry showed better aerodynamic performance, which results in weaker tip leakage vortex and lower tip leakage flow rate with respect to the plane tip geometry.

کلیدواژه‌ها [English]

  • Axial turbine
  • External cooling
  • Squealer
  • Film-cooling effectiveness
  • Aerodynamic performance

مراجع

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نشریه مهندسی مکانیک امیرکبیر
دوره 53، شماره 3
خرداد 1400
صفحه 1521-1536

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