Hydrodynamic Characteristics of Single and Multi-Row Heat Exchangers Employing Staggered Drop-Shaped Tubes

In this work, the influence of the number of tube rows and the Reynolds number on the thermal aerodynamic characteristics of staggered drop-shaped tube bundles was analyzed. A similarity equation was developed to describe the aerodynamic drag coefficient f of a drop-shaped tube bundle, taking into account the number of tube rows NR. Drop-shaped tubes were arranged in a staggered pattern and placed in consecutive rows in the direction of flow (from 1 to 20 rows), each of which consists of 7 tubes in the transverse direction. The Reynolds number Re ranged from 1780 to 18720. The results showed that f decreases with increasing Re. Moreover, an increase in NR leads to an increase in the drag coefficient. f increases by about 18.59–21.91 times with an increase in NR from 1 to 20. The maximum error between the numerical results and the similarity equation obtained on their basis was ± 8.18%.

Drop-shaped tube, non-circular tube, number of tube rows, Reynolds number, similarity equation, drag coefficient, numerical study, Fluent.

Volume 23, issue 4, 2022 year

Гидродинамические характеристики однорядных и многорядных теплообменников с шахматным расположением каплевидных труб

В данной работе проводится численное исследование влияния числа Рейнольдса Re и количества рядов труб NR на аэродинамические характеристики шахматного пучка труб каплевидной формы. Разработано уравнение подобия для описания коэффициента аэродинамического сопротивления f пучка каплевидных труб с учетом количества рядов труб. Трубы расположены в шахматной компановке и размещены последовательными рядами в направлении потока (от 1 до 20 рядов), каждый из которых состоял из 7 труб в поперечном направлении. Исследование выполнено для диапазона числа Рейнольдса 1780-18720. Было найдено, что f уменьшается с увеличением Re. Более того, увеличение NR приводит к увеличению коэффициента аэродинамического сопротивления. f увеличивается в 18,59 – 21,91 раза при увеличении NR от 1 до 20. Максимальное отклонение между численными результатами и полученными на их основе уравнением подобия составило ±8,18%.

Каплевидная труба, некруглая труба, число рядов труб, число Рейнольдса, корреляция, уравнение подобия, коэффициент аэродинамического сопротивления, теплообменник, численное исследование, Fluent

Volume 23, issue 4, 2022 year

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