Effect of passive commutation on heat transfer and flow characteristics of non-circular pipes

Abstract

Based on the need for energy-saving and consumption reduction in industrial applications, the effect of an internal concave structure on a heat exchanger tube with a right-angle trapezoidal cross-section and changing the flow direction on the heat transfer and flow characteristics in the tube was investigated. CFD techniques were used to study the effect of the inner concave structure with 15mm and 30mm center spacing and 1.88mm and 3.75mm radius of curvature on the heat transfer and flow characteristics of air under turbulent flow conditions in the range of Re13349 to 57847, and the heat transfer law was explored in terms of the combined heat transfer performance PEC and the coefficient of variation of the convective heat transfer coefficient and verified to be consistent with the field The effect of the variation of the synergy angle was confirmed. The results show that the PEC of the pipe is enhanced with the increase of the inner concave radius and the decrease of the inner concave center spacing.