Thermal performance assessment of self-rotating twisted tapes and Al2O3 nanoparticle in a circular pipe

• 作者: Chuanshuai Dong Lin Lu Tao Wen Shaojie Zhang
• 来源期刊: 中国化学工程学报（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: Fluid Dynamics and Transport Phenomena
• 页码范围: 77-86
• 页数: 10页
• 语种: 英文

摘要

In view of the practical importance of the heat transfer devices in various thermal engineering fields including chemical and nuclear engineering, this study aims at developing an effective method of heat transfer enhancement by using self-rotating twisted tapes (SRTTs) and Al2O3 nanoparticles. The effect of the self-rotating twisted tapes and Al2O3 nanoparticles on the thermal performance was comprehen-sively investigated in a circular pipe. The experimental results indicated the heat transfer rate was effec-tively improved by SRTTs in comparison of plain tube. In addition, the heat transfer multiplier with SRTTs decreased from 1.38 to 1.08 with the Reynolds number increasing from 19,322 to 64,407, while the fric-tion factor multiplier decreased from 1.61 to 1.32. Besides, the results indicated that the employment of Al2O3 nanoparticles and SRTTs demonstrated superior thermal performance to the single SRTTs. As Reynolds number increases from 19,322 to 64,407, the heat transfer multiplier decreased from 2.08 to 1.18 in the mass concentration of 3.0％ and from 1.38 to 1.08 in mass concentration of 0.0％. Finally, the new heat transfer and friction factor correlations considering the combined effect of Al2O3 nanopar-ticle and SRTTs were developed within 10％deviation of experimental values.