Statistical analysis and shape optimization of a finned corrugated heat exchanger using RSM

Abstract

The effect of geometry on the performance of a corrugated double-pipe heat exchanger with a hot inner tube was thoroughly investigated. The optimized exchanger geometry was determined by the Response Surface Methodology (RSM). Firstly, heat transfer parameters were numerically obtained using the finite volume method for various hot tube geometries, namely spiral, circular, cylindrical, spherical, and close-packed semi-cylindrical winglets. The maximum thermal performance was exhibited in Re = 400 for spiral fin, equal to 1.82. Secondly, the spiral inner tube was modeled to analyze the number of fins and the fin pitch. The RSM was subsequently employed to analyze for different velocities various geometries featuring 0–4 fins and fin pitches in the range of 300 mm to 600 mm. Also, to enable a more comprehensive application of the results, a statistically obtained accurate relation is presented for the convective heat transfer coefficient in terms of the number of fins, fin pitch, and flow velocity. By performing optimizations using various geometries with different boundary conditions for the first time, this article can serve as a solid base for heat exchanger selection.