Experimental Investigation of Flow Induced Noise Around Circular Cylinder by Measuring Unsteady Surface Pressures
Message:
Abstract:

In the present study, noise emission from a circular cylinder model with 22 mm diameterand 500 mm length has been experimentally investigated. For this purpose, the surface pressurefluctuations have been measured both in spanwise and azimuthal directions by employing miniaturecondenser microphones, Pa-WM-61A. All the experiments are carried out in a subsonic wind tunnel withthe turbulence intensity of 0.3% and maximum upstream velocity of 25 m/s. The results show that tonalnoise for velocities of 10, 15 and 20 m/s takes place at vortex shedding frequencies of 98, 142 and 186Hz respectively which correspond to typical Strouhal number of 0.2. Moreover, frequency of the firstand second harmonic occurs at two and three times of the vortex shedding frequency respectively. In thisstudy, the best collapses of the surface pressure spectra at low and middle frequencies can be obtainedusing the upstream flow scales whereas at high frequencies data are collapsed by employing downstreamscales at vortex formation location. Furthermore, the longitudinal and lateral coherences can provideadequate information about the lifespan (or, inversely, the decay) of eddies and their physical size.

Article Type:
Research/Original Article
Language:
Persian
Published:
Amirkabir Journal Mechanical Engineering, Volume:51 Issue:2, 2019
Pages:
329 - 346
magiran.com/p2036104  
روش‌های دسترسی به متن این مطلب
اشتراک شخصی
در سایت عضو شوید و هزینه اشتراک یک‌ساله سایت به مبلغ 300,000ريال را پرداخت کنید. همزمان با برقراری دوره اشتراک بسته دانلود 100 مطلب نیز برای شما فعال خواهد شد!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی همه کاربران به متن مطالب خریداری نمایند!