Abstract
A floatation nozzle can effectively transfer heat and dry without touching the substrate, and serves as a vital component for heat transfer to the substrate. Enhancing the heat transfer performance, and reducing its heat transfer unevenness to the substrate play an important role in improving product quality and reducing thermal stress. In this work, the effects of key structural parameters of the floatation nozzle on the heat transfer mechanism are systematically investigated by means of a numerical simulation of computational fluid dynamics. The findings demonstrate that the secondary vortex structure induced by the floatation nozzle with effusion holes increases heat transfer performance by 254.3% compared with the nozzle without effusion holes. The turbulent kinetic energy and temperature distribution between the jet and the target surface are affected by the jet angle and slit width respectively, which change the heat transfer performance of the float nozzle in different degrees. Furthermore, to improve the comprehensive heat transfer performance of the floatation nozzle structure, taking into account the average heat transfer capability and heat transfer uniformity, the floatation nozzle’s design is optimized by the application of the response surface method. The comprehensive heat transfer performance is increased by 26.48% with the optimized design parameters. Our work is of practical value for the design of floatation nozzles with high heat transfer performance to improve product quality in industrial systems.