增材制造蒸汽发生器特征流道的传热特性研究OA

To enhance the heat transfer performance of steam generator channels,this study fabricated three hexagonal nar-row channel test samples with rib structures having different twist angles using metal additive manufacturing.Systematic gas-liquid two-phase flow heat transfer experiments and numerical simulations were conducted.The experiments were car-ried out in an open-loop circulation system,where the mass flow rate and heat flux density were varied to obtain convective heat transfer coefficients in single-phase liquid,subcooled boiling,saturated boiling,dryout,and single-phase gas regions,and compared with common empirical formulas.The results showed that the mass flow rate significantly enhanced heat transfer across all regions.High heat flux density strengthened heat transfer in the low gas content region but had little effect in the high gas content region.The larger the twist angle,the stronger the secondary flow and interface renewal,leading to higher heat transfer capability.Numerical simulations further revealed the influence of the twisted ribs on the convective flow structure and bubble distribution.In the single-phase gas region,traditional empirical formulas significantly underesti-mated the heat transfer performance,while a new empirical correlation proposed based on experimental data significantly improved prediction accuracy.The study confirms the feasibility of additive manufacturing in enhancing heat transfer in steam generator channels and provides a basis for structural optimization.