Thermal-hydraulic performance of a nanofluid in a shell-and-tube heat exchanger equipped with new trapezoidal inclined baffles: Nanoparticle shape effect

The influences of diverse shapes of nanoparticles on thermal-hydraulic efficacy of a nanofluid having boehmite nanoparticles in a shell and tube heat exchanger (STHE) are analyzed. The shell-side of the STHE is equipped with novel trapezoidal inclined baffles to develop torsional flows. The nanofluid with five different particle shapes is selected as the hot liquid in the tube-side, whereas the pure water is adopted as the cold liquid in the shell-side. When enhancing the cold fluid's Reynolds number, the pressure loss, overall heat transfer cofficient, heat transfer rate, effectiveness, and Number of Transfer Units (NTU) increase, while the performance index decreases. The nanofluid with platelet particles causes the greatest overall heat transfer cofficient, while that with the Os nanoparticles presents the smallest pressure loss. Additionally, the nanofluid with the Os nano particles presents the greatest effectiveness, pursued by the nanoparticle suspensions with the brick-, blade-, cylinder-, and platelet-shaped particles, respectively. (c) 2021 Elsevier B.V. All rights reserved.