Investigation of thermal analysis and pressure drop in non-continuous helical baffle with different helix angles and hybrid nano-particles

Abstract

In this study, shell and tube heat exchanger with non-continuous helical baffles (NCHB-STHX) is modeled numerically. This heat exchanger has varied applications in different fields of science and industry. The ratio of heat transfer coefficient to pressure drop (HTC/ΔP) is obtained from different angles and intensities. Helix angles vary from 20° to 40°, mass flow rate amounts are 0.984, 1.33 and 1.685 kg/s, and hybrid Nanofluid alumina-Cu-water with three different intensities 0.33, 1, and 2% were tested individually. In addition, the results were compared with pure water. Reynolds number ranges are between 25000 and 31000, and the K-ε RNG model was chosen as the most suitable one. Results show that the heat transfer at β = 20° is maximum and the optimum pressure drop occurs at β = 40°. Also, the helix angle β = 20°, 2% intensity of hybrid Nanofluid alumina-Cu-water and 1.685 kg/s flow rate thermal efficiency is maximum for the helix angle. As the Reynolds number increases up to 80%, HTC rises to approximately 84%. On the other hand, it declines gradually as the helix angle raises nearly 50% when it comes to alumina-Cu-water Nanofluid. The ratio (HTC/ΔP) is at its highest and has a 6% improvement compared to the previous study.

Keywords

• Helical baffle
• Heat transfer
• Hybrid Nanofluid
• Finite volume method (FVM)
• Pressure drop