Improving the efficiency of drop-shaped tube bundles by controlling the angle of attack

In the present work, a numerical study of the possibility of increasing the thermal-hydraulic performance of drop-shaped tube bundles was carried out by controlling the angle of attack θ from 0° to 360°. The Reynolds number Re ranged from 1780 to 18700. Ten cases of twenty-row circular and drop-shaped tube bundles in in-line and staggered arrangement were considered. The results of numerical simulation showed that the maximum values of the thermal-hydraulic performance can be achieved for a number of studied bundles, while the best ones were for the case 6 (θ_(1-5)=0°, θ_(6-10)=330°, θ_(11-15)=30°, θ_(16-20)=0°), which were greater by 65.9 – 71.54% and 63.18 – 75.93% than those for the case 3 (staggered drop-shaped tube bundle, θ_(1-20)=0°) and case 1 (staggered circular tube bundle), respectively. Formulas was developed for calculating the average Nusselt number and thermal-hydraulic performance for case 6 with a maximum deviation of 0.74% and 0.48%, respectively.

drop-shaped tube, circular tube, heat exchanger, heat transfer, Nusselt number, efficiency, numerical study, Fluent

Volume 24, issue 3, 2023 year

Повышение эффективности пучков каплевидных труб за счет управления углом атаки

В настоящей работе проведено численное исследование возможности повышения термогидродинамической эффективности пучков каплевидных труб за счет управления углом атаки θ от 0° до 360°. Исследование характеристик теплообмена проводилось в диапазоне чисел Рейнольдса от 1780 до 18700. Рассмотрены десять случаев пучков труб круглой и каплевидной формы с коридорным и шахматным расположением. Результаты численного моделирования показали, что максимальные значения общей теплогидродинамической эффективности могут быть достигнуты для ряда исследованных конфигураций, при этом наиболее удачные – для случая 6 (θ_(1-5)=0°, θ_(6-10)=330°, θ_(11-15)=30°, θ_(16-20)=0°) превышают на 65,9 – 71,54 % и 63,18 – 75,93 %, наименее удачные конфигурации, как в случае 3 (шахматный пучок каплевидных труб, θ_(1-20)=0°) и в случае 1 (шахматный пучок круглых труб), соответственно. Разработаны формулы для расчета среднего числа Нуссельта и эффективности для случая 6 с максимальным отклонением 0,74 % и 0,48%, соответственно.

каплевидная труба, круглая труба, теплообмен, теплообменник, число Нуссельта, эффективность, численное исследование, Fluent

Volume 24, issue 3, 2023 year

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