Numerical analysis of flow and heat characteristic around micro-ribbed tube in heat exchanger system

• Published in: Powder technology Vol. 395; pp. 562 - 583
• Main Authors: Tu, Jianglin, Qi, Cong, Li, Keao, Tang, Zhibo
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.01.2022; Elsevier BV
• Subjects: Energy utilization; Enhanced heat transfer; Fluid flow; Heat exchangers; Heat transfer; Mathematical models; Micro-rib structure; Nanofluids; Numerical analysis; Numerical simulation; Reynolds number; Titanium dioxide; Numerical simulation; Micro-rib structure; Enhanced heat transfer; Nanofluids
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2021.10.009

In order to improve the energy utilization rate, this paper analyzes the flow around the cylinder in the tube-row channel heat exchanger through numerical simulation. Effects of micro-rib structure types (vertical rib and ring rib), number of ribs (N = 0, 4, 6, 8), height of ribs (H = 2, 3, 4 mm), pitch diameter ratio (ST/D = 1.5, 2, 2.5), mass fractions (ω = 0–0.5%) and Reynolds numbers (Re = 514–1205) on the flow and heat transfer characteristics of tube-row channel heat exchangers are analyzed. Results showed that TiO2-H2O nanofluids can improve the comprehensive performance of heat exchanger, and when the mass fraction is 0.4%, the tube-row channel heat exchanger has the best performance. For heat exchangers with different types and structural parameters, the adjustment of the number of ribs, the height of ribs, the ratio of transverse pitch diameter and the use of nanofluids can increase Nusselt numbers by 53.63%, 57.25%, 52.38% and 12.93% at maximum, respectively. [Display omitted] •Effects of micro-rib type on tube heat exchanger are studied.•Effects of fin structure parameters on tube heat exchanger are studied.•Heat transfer performance of annular fins is better than that of vertical fins.•Comprehensive evaluation index of the tube row channels can reach 2.89.