Abstract

An attempt is made to improve the overall performances of channel heat exchangers. The techniques of baffles and nanofluids are combined to enhance the dynamic and thermal behaviors within the channel exchanger. Baffles under various attack angles are used as vortex generators. In addition, oil/multiwalled carbon nanotubes (MWCNT) is used as a working fluid. Both inclinations in the upstream and downstream directions were considered, referenced as Case A (UIB) and Case B (BIB), respectively. While the channel equipped with vertical baffles is referenced as Case C. The proposed models with combined techniques allowed a considerable enhancement in the overall efficiency. The comparison between the three cases revealed that the most significant value of thermal enhancement factor (TEF) of 5.634 was reached with vertical baffles (Case C) at the highest value of Reynolds number. When using inclined baffles, the 75° upstream attack angle (Case A) allowed the highest TEF of 4.814, compared with Case B.

摘要

试图改善通道热交换器的整体性能。挡板和纳米流体的技术相结合，以增强通道交换器内的动态和热行为。在各种迎角下的挡板用作涡流发生器。另外，油/多壁碳纳米管（MWCNT）用作工作流体。考虑了上游和下游两个方向的倾斜，分别称为案例A（UIB）和案例B（BIB）。将配备垂直挡板的通道称为案例C。所提出的模型结合了组合技术，可以显着提高整体效率。三种情况的比较显示，热增强因子（TEF垂直挡板（情况C）在雷诺数的最大值处达到5.634的）。当使用倾斜挡板时，与情况B相比，75°上游迎角（情况A）允许最高TEF为4.814。