In this study, a series of low-concentration carbon nanotubes (CNT) water-based nanofluids (0.0055, 0.055, 0.111 and 0.278 vol%) were used as coolants in a shell and tube cooler of the residue fluid catalytic cracking gasoline product to analyze their effects on heat performance of the heat exchanger. The coolants and gasoline flow in tube side and shell side, respectively. This work was performed through simulating the heat exchanger by ASPEN HTFS+ 7.3 software. The performance of the nanofluids to heat transfer was analyzed in comparison with cooling water. Results illustrated that 0.055% CNT concentration could enhance heat transfer properties of the heat exchanger such as Nusselt number, total heat transfer coefficient and heat transfer rate more than other concentrations. Therefore, the lowest temperature of outlet shell-side fluid was also observed at this concentration. Moreover, increment in mass flow rates of both the tube-side and shell-side fluids caused enhancement of the heat transfer, especially with 0.055 vol% CNT. Although there is an optimum concentration among the studied CNT volume fractions, all nanofluids exhibit better thermal performance of the heat exchanger than cooling water, whereas pressure drop increases with CNT loading.

中文翻译：

---

水基碳纳米管纳米流体在残油催化裂化装置汽油产品的壳管式换热器中的传热

在这项研究中，将一系列低浓度碳纳米管（CNT）水性纳米流体（0.0055、0.055、0.111和0.278 vol％）用作残液催化裂化汽油产品的管壳式冷却器中的冷却剂，以进行分析它们对热交换器的热性能的影响。冷却剂和汽油分别在管道侧和壳体侧流动。这项工作是通过使用ASPEN HTFS + 7.3软件模拟热交换器进行的。与冷却水相比，分析了纳米流体的传热性能。结果表明，0.055％的CNT浓度比其他浓度能更有效地提高热交换器的传热性能，如Nusselt数，总传热系数和传热速率。因此，在此浓度下，也观察到出口壳侧流体的最低温度。而且，管侧和壳侧流体的质量流率的增加引起传热的增强，特别是对于0.055vol％的CNT。尽管在所研究的CNT体积分数中存在最佳浓度，但是所有纳米流体都比冷却水表现出更好的热交换器热性能，而压降随CNT负载的增加而增加。