An Experimental Study of Shell-and-Tube Heat Exchangers With Continuous Helical Baffles

Abstract

Two shell-and-tube heat exchangers (STHXs) using continuous helical baffles instead of segmental baffles used in conventional STHXs were proposed, designed, and tested in this study. The two proposed STHXs have the same tube bundle but different shell configurations. The flow pattern in the shell side of the heat exchanger with continuous helical baffles was forced to be rotational and helical due to the geometry of the continuous helical baffles, which results in a significant increase in heat transfer coefficient per unit pressure drop in the heat exchanger. Properly designed continuous helical baffles can reduce fouling in the shell side and prevent the flow-induced vibration as well. The performance of the proposed STHXs was studied experimentally in this work. The heat transfer coefficient and pressure drop in the new STHXs were compared with those in the STHX with segmental baffles. The results indicate that the use of continuous helical baffles results in nearly 10% increase in heat transfer coefficient compared with that of conventional segmental baffles for the same shell-side pressure drop. Based on the experimental data, the nondimensional correlations for heat transfer coefficient and pressure drop were developed for the proposed continuous helical baffle heat exchangers with different shell configurations, which might be useful for industrial applications and further study of continuous helical baffle heat exchangers. This paper also presents a simple and feasible method to fabricate continuous helical baffles used for STHXs.

Numerical Investigation of the Effect of Variable Baffle Spacing on the Thermal Performance of a Shell and Tube Heat Exchanger

“…They also direct the shell side flow to enhance the heat transfer coefficient but their usage conversely produces an increased pressure drop [6]. Therefore, their dimensions and locations have to be optimized or they have to be replaced with the other types which have better heat transfer efficiency and lower pressure drops [7][8][9][10]. There are numerous studies on the impact of the baffle cut, number of baffles, baffle type, etc.…”

Flow and heat transfer performances of helical baffle heat exchangers with different baffle configurations

“…Zeng et al [11] experimentally studied two continuous helical baffle heat exchangers with middle and tangential inlet/outlet, and found these two schemes performed worse than both schemes of the quadrant helix baffles and segment baffles in terms of comprehensive index.…”

“…With respect to continuous helical baffle heat exchangers, Peng et al [9] and Wang et al [10] experimentally studied continuous helical baffle heat exchangers compared with the non-continuous helical baffle schemes and segmental ones, and showed that the performance gain of the continuous helical baffle heat exchangers are rather limited. Zeng et al [11] experimentally studied two continuous helical baffle heat exchangers with middle and tangential inlet/outlet, and found these two schemes performed worse than both schemes of the quadrant helix baffles and segment baffles in terms of comprehensive index.…”

Numerical Simulation of Heat Transfer in Finned Tube of Heat Recovery Unit Using Fluid-Solid Coupled Method

“…There are many researches about the shell-and-tube heat exchanger. By changing the structural parameters of baffles [1,2], fins [3,4], tapes [5], and other accessories, the heat exchange efficiency was improved. Experiments are proved to be the most reliable and direct research method.…”