Comparison of selected shell and tube heat exchangers with segmental and helical baffles

Abstract

A shell and tube heat exchanger (ST) is analyzed numerically and experimentally using various configurations of baffles. The baffles used are segmental baffle (SB) with baffle cut of 300 (SB-30), 500 (SB-50), Align baffle with baffle cut of 300 (AB-30) and 500 (AB-50). The numerical study of ST with different configurations shows that AB-30 has superior effectiveness than other configurations. The comparison of numerical and experimental results of AB-30 shows a deviation of 10.1%. The study also includes a comparison of the segmental baffle (STs) with continuous helical baffles with a helix angle of 250 (STc) experimentally. The comparative analysis, drawn between STs and STc shows that STs have better effectiveness at all considered mass flow rates varied between 0.00005 to 0.00018 m3/s. Lower mass flow rate had shown better effectiveness than STs by 27.7%. The fixed helix angle of 25° was provided to helical baffles, results in increased heat transfer coefficient (HTC) at the lower pressure drop. The flow pattern in the shell for both STs and STc maintained forced helical and rotational due to the geometry pattern of the baffles, respectively. Based on the experimental data, the non-dimensional parameters for HTC and pressure drop (ΔPo) is calculated for both the configurations. However, for the optimal design of the heat exchanger, the maximum heat recovery rate has also been computed using the composite hot and cold diagram for different configurations.