Numerical study on heat transfer and pressure drop characteristics of plain-finned tube under high temperature

In the present paper, numerical study on the heat transfer and pressure drop characteristics of the gas side in the plain-finned tube was performed and compared under two different conditions, i.e., high temperature and constant temperature. The results indicated that the Nusselt number was affected by the inlet temperature and the friction factor was affected by the temperature difference. The radiation had a significant effect on the Nusselt number, but little effect on the friction factor. It could be concluded that the heat transfer and pressure drop characteristics of the plain-finned tube under high temperature were different from that under constant temperature, which could not be directly used in the high temperature environment during the thermal design.