THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Shiquan Zhu

,

Longjiang Li

,

Zongyao Hu

,

Tian Qi

,

Shuang Cao

,

Zhenya Zhang

,

Yisen Peng

online first only

Investigations of thermohydraulic performance in heat exchanger tube with rectangular vortex generators

ABSTRACT
To demonstrate the rationalization of multi-longitudinal swirls (MLSs) in heat exchanger tubes, this paper investigates the thermohydraulic performance of heat exchanger tube with rectangular vortex generator using numerical simulation. Comparative analyses of rectangular vortex generators and their different slotted structures are conducted, along with the investigation of the effect of the longitudinal pitch (P = 0.1 m, 0.2 mand0.3 m) of the rectangular vortex generators on the thermohydraulic performance. The research reveals that the MLSs induced by the vortex generator inside the tube accelerate the exchange of cold and hot fluids, improve the field synergies of velocity vectors and temperature gradients, and enhance the heat transfer efficiency of the heat exchanger tube. The slotted structure reduces the flow resistance and lowers the degree of disturbance to the fluid, which reduces the strength of the MLSs, thus weakening the overall performance of the heat exchanger. The strength of the MLSs has a direct influence on the overall performance of the heat exchanger tube. With the increase of P, the performance evaluation criteria (PEC) of the heat exchanger tubes decreases, and the maximum PEC = 1.44 is obtained for P = 100 mm at the studied Reynolds number range.
KEYWORDS
thermohydraulic performance, rectangular vortex generators, multi-longitudinal swirls, numerical simulation
PAPER SUBMITTED: 2023-11-27
PAPER REVISED: 2024-01-12
PAPER ACCEPTED: 2024-01-25
PUBLISHED ONLINE: 2024-04-14
DOI REFERENCE: https://doi.org/10.2298/TSCI231127088Z
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Investigations of thermohydraulic performance in heat exchanger tube with rectangular vortex generators