Experimental investigation on thermal-hydraulic performance of a novel shell-and-tube heat exchanger with unilateral ladder type helical baffles

A novel structure of the shell-and-tube heat exchanger with unilateral ladder type helical baffles (STHX-ULHB) is proposed. Compared with the shell-and-tube heat exchanger with segmental baffles (STHX-SB), the heat transfer and pressure drop performances of the STHX-ULHB are experimentally investigated. The experimental results show that both the shell-side heat transfer coefficient it, and the overall heat transfer coefficient K of the STHX-ULHB are dramatically increased with the increasing of the mass flow rate, which are 109.3-125.5% and 105.2-122.5% higher than that of the STHX-SB, respectively. The pressure drop of the STHX-ULHB is decreased by 12.1-45.9% than that of the STHX-SB. Two criteria, i.e., the heat transfer coefficient per unit pressure drop and the thermal performance enhancement factor (TEF), are introduced to evaluate the comprehensive performance of the STHX-ULHB. Overall, the shell-side heat transfer coefficient per unit pressure drop of STHX-ULHB is 151.9%-176.4% higher than that of the STHX-SB. The values of the TEF of the STHX-ULHB increase by 161.3-178.9%, with an average value of 171.2%. Both of the results illustrate that the comprehensive performance of the STHX-ULHB is superior to that of the STHX-SB.