مطالعۀ عددی تولید صدا در جریان حول سیلندر مربعی در زوایای حملۀ مختلف

نوع مقاله : مقاله پژوهشی

نویسندگان

یزد

چکیده

پارامترهای جریان و سطح فشار صوت در دوردست آکوستیکی و برروی سطح یک سیلندر مربعی در شش زاویۀ حملۀ مختلف مورد بررسی قرار گرفته است. حل عددی با نرم‌افزار تجاری فلوئنت و بااستفاده از مدل اغتشاشی رهیافت گردابه‌های بزرگ شبیه‌سازی شده است. از مقایسۀ نتایج حل عددی با نتایج تجربی موجود، مشخص گردید که نتایج حل جریان و سطح فشار صوت مطابقت قابل قبولی با نتایج تجربی دارند. کمترین مقدار ضرایب متوسط نیروهای برآ و پسا و مجذور میانگین مربعات نیروی برآ در محدودۀ زاویۀ حملۀ 13 درجه روی داده و نیز کمترین مقدار سطح فشار صوت در دوردست آکوستیکی نیز در این محدوده واقع شده است که متأثر از حداقل شدن نوسانات نیروی برآ و پسا است. میدان آکوستیکی تولید شده ناشی از نوسانات نیروی برآی وارد بر سیلندر می باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical Investigation of Flow Induced Sound Around a Square Cylinder at Various Incidence Angles

نویسندگان [English]

  • mohsen mohammadrezaei
  • Ali Akbar Dehghan
  • Alireza Movahedi
Yazd university
چکیده [English]

Flow characteristics and sound pressure level in the acoustical far field and on the surface of a square cylinder at incidence are investigated for six angles of attacks. Flow around square cylinder is modeled using large eddy simulation method. The flow simulation is conducted using fluent commercial software. The results of the present study showed good agreement with the available experimental results. The minimum of drag coefficient, mean and root mean squared (rms) value of lift coefficient, and sound pressure level in acoustical far field occurred at 13o angle of attack which is due to the lowest values of fluctuating lift and drag forces at this angle of attack. The induced acoustic field is due to the fluctuating lift force acting on the rod.

کلیدواژه‌ها [English]

  • Square cylinder
  • sound pressure level
  • turbulence
  • large eddy simulation
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