Effect of helical baffles and water‐based Al<sub>2</sub>O<sub>3</sub>, CuO, and SiO<sub>2</sub>nanoparticles in the enhancement of thermal performance for shell and tube heat exchanger
Ravi Gugulothu, Narsimhulu Sanke
Abstract
Abstract In this study, Shell and tube heat exchanger (STHX) with 22% cut segmental baffles and helical baffles with 20°, 30°, 40° inclination angles are considered for three‐dimensional CFD analysis using the ANSYS FLUENT tool to investigate the performance of STHX. OHTC and comprehensive performance index are higher for 40° helical baffles when compared to segmental baffle and 20°, 30° helical baffle heat exchangers with water as working fluid. Hence, further investigations are carried out for 40° helical baffle heat exchangers. Numerical investigations are extended with nanofluids (Al 2 O 3 , CuO, and SiO 2 ) at 1%, 3%, and 5% volume concentrations for each nanofluid. Under the same mass flow rates, 40° helical baffles with Al 2 O 3 nanofluid as working fluid provided better heat transfer rates when compared to the other two nanofluids and base fluid. Also, the authors noticed that the 5% volume (vol) concentration nanofluids provided better heat transfer enhancements when compared to 1%, 3% volume concentrations, and base fluid. Enhancements (10.33%–8.24%) from lower to the higher mass flow rate in 40° HB with Al 2 O 3 nanofluid at 5% volume concentration are observed when compared to water as base fluid.