Heat transfer characteristics of a short helical plate in a horizontal circular tube

Enhancement techniques based on artificial roughness are used in numerous applications of heat exchangers. Heat exchange devices are essential components in complex engineering systems, such as industrial energy generation and energy conversion. In this study, a short helical plate was used to enhance heat transfer in a horizontal circular annulus tube. Experiments and CFD were performed to study the heat transfer effect of the helical plate, and Teflon and brass materials were used for the helical plate. Uniform heat flux was considered, and particle image velocimetry (PIV) was used for comparisons. The Nusselt number profiles increased steeply around the Teflon helical plate and decreased suddenly to 1.0 along the test section.