A two-level Plackett-Burman non-geometric experimental design for main and two factor interaction sensitivity analysis of zigzag-channel PCHEs

Abstract

Supercritical carbon dioxide (sCO2) is currently being studied as the working fluid in producing power using the Brayton cycle due to its excellent physical and thermodynamic properties, especially near the critical point. Printed circuit heat exchangers (PCHEs) are being considered for use as condensers and recuperators for this purpose due to their high strength and compact designs. This paper examines the sensitivity of the Nusselt number (Nu), Colburn factor (j), and Fanning friction factor (f) for zigzag-channel PCHEs to 20 geometric design factors and operating conditions. A two-level Plackett-Burman, non-geometric resolution III experimental design with no replications was used. This experimental design was then folded over to produce a resolution IV design to eliminate confounding of main factor effects. Main factor and two factor interaction effects were examined. Computational fluid dynamics (CFD) was used to simulate each tested case. Data indicates that zigzag-channel PCHE thermal-hydraulic performance parameters are most sensitive to changes in channel bend angle, bend angle radius of curvature, mass flow rate, and channel width. Additionally, some two factor interactions of the more significant main factors were found to be of importance.