کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7060235 | 1458493 | 2016 | 30 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Air-water flow characteristics in high-velocity free-surface flows with 50% void fraction
ترجمه فارسی عنوان
خصوصیات جریان آب در جریانهای آزاد با سرعت بالا با 50 درصد ضخامت فاضلاب
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
جریان آزاد بدون سریع، مقیاس زمان آب هوا، هوادهی فضایی، تعاملات قطره حباب، خواص جریان مایکروویو، فرکانس های مشخص،
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
جریان سیال و فرایندهای انتقال
چکیده انگلیسی
High-velocity free-surface flows are complex two-phase flows and limited information is available about the interactions between air and water for void fractions of about 50%. Herein a detailed experimental study was conducted in the intermediate flow region (C â¼ 50%) on a stepped spillway and the microscopic air-water flow characteristics were investigated. The results showed differences in water and droplet chord times with comparatively larger number of air chord times (0-2Â ms), and larger number of water chord times (2-6Â ms). A monotonic decrease of particle chord modes was observed with increasing bubble count rates. Several characteristic time scales were identified based upon inter-particle arrival time analyses of characteristic chord time classes as well as spectral analyses of the instantaneous void fraction signal. Chord times of 3-5Â ms appeared to be characteristic time scales of the intermediate flow region having similar time scales compared to the local correlation and integral turbulent time scales and to time scales associated with bubble break-up and turbulent velocity fluctuations. A further characteristic time scale of 100Â ms was identified in a frequency analysis of instantaneous void fraction. This time scale was of the same order of magnitude as free-surface auto-correlation time scales suggesting that the air-water flow structure was affected by the free-surface fluctuations.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Multiphase Flow - Volume 85, October 2016, Pages 186-195
Journal: International Journal of Multiphase Flow - Volume 85, October 2016, Pages 186-195
نویسندگان
Stefan Felder, Hubert Chanson,