Numerical study of heat transfer in multigap, parallel 45°-angled rib turbulators

Abstract

In this study, the flow characteristics and heat transfer performance of rib channel installed with four types of multigap, 45°-angled rib turbulators on the top and bottom walls are numerically investigated using ANSYS Fluent version 19, and an optimal rib structure that facilitates enhanced heat transfer performance is determined. The analyzed structures are as follows: Case 1: inline-type ribs without gaps, Case 2: inline-type ribs with multiple gaps (similar gaps on the top and bottom walls), Case 3: staggered-type ribs with multiple gaps, and Case 4: inline-type ribs with multiple gaps (different gaps on the top and bottom walls). The numerical results show that the presence of multiple gaps within the rib channel (Cases 2, 3, and 4) generates additional flows, increases the vortical motion and secondary recirculation flow, and decreases the pressure loss. In addition, the staggered-type rib structure in Case 3 generates multiple vortical motions and enhances the mixing flow to improve the heat transfer performance. Therefore, a multigap, staggered-type rib structure in a parallel 45°-angled rib channel is most effective in increasing the heat transfer and decreasing the pressure loss.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

(1) This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20182510102380). (2) The project code of this work for Korea Institute of Geoscience & Mineral Resources (KIGAM) is NP2018-027.