Parameters optimization of a parallel-flow heat exchanger with a new type of anti-vibration baffle and coiled wire using Taguchi method

This study presents the thermal-hydraulic optimization of the design parameters of a parallel-flow shell-and-tube heat exchanger with a new type of anti-vibration hexagon clamping baffle and equilateral triangle cross-sectioned coiled wire. A periodic flow unit duct with non-staggered tube layout is adopted as the numerical analysis model by Fluent. The Taguchi method is used to explore the influence of five geometric parameters including baffle distance (A), baffle width (B), coil diameter (C), coil pitch (D), and the side length of the equilateral triangle (E). An L18 (3⁵) orthogonal array is chosen to carry out the numerical simulation. The comprehensive thermal-hydraulic performance evaluation criterion (PEC) is set as the optimization goal. The results show that the order of the factor effectiveness for the Nusselt number is E>C>A>D>B, for the flow friction is C>E>A>B>D and for the PEC is C>E>A>B>D. This means that the coil pitch has a great influence while the baffle width and the coil diameter have a trifling effect. Finally, the optimal factor combination for PEC is obtained. The PEC of the optimal combination is 0.19%–1.92% higher than the model with better comprehensive performance among 18 cases for Reynolds number in the range from 14 465 to 32 547.