Thermal-hydraulic characteristics and correlation development of inclined wave shoveled fin under reverse flow

Conventional flying-wing fins have limited flow-field regulation capacity, with their passive heat-transfer enhancement approaching the performance limits. Accordingly, this paper proposes a novel Inclined wave shoveled fin (IWSF) geometrically modified from flying-wing fins. Three-dimensional numerical simulations using the RNG k-ε turbulence model are conducted to explore the thermal-hydraulic characteristics of IWSF under reverse flow conditions for Re ranging from 1500 to 3000. Five key geometric parameters (inclination angle θ , wave amplitude A , wavelength L , fin pitch F p and fin thickness F t ) are systematically analyzed. The Taguchi method is adopted to quantify parameter contribution ratios and screen configurations for maximum heat transfer rate, minimum flow resistance and optimal comprehensive performance. Quadratic predictive correlations for the j -factor and f -factor are established via response surface methodology (RSM) based on 48 numerical samples. Results show that the inclined geometry generates remarkable diversion effects and reconstructs internal flow field inside the channel. At θ = 62.5°, the JF -factor rises by 24.30% relative to the non-inclined flying-wing fin. Both correlations yield coefficients of determination R 2 > 0.95, with a maximum prediction error below 10%. The present findings offer theoretical references for fin design and engineering applications of compact heat exchangers without contact thermal resistance.