为解决大流量(≥600 m³/h)工况下氢气与天然气直接掺混时混合不均与压损过高的问题,探索通过结构优化实现无辅助设备条件下的高效低阻混合。基于传统T型管结构,选取了包括氢气入口数量、入口角度、入口位置及水平管直径等关键结构参数,采用正交试验法设计了数值模拟方案,并结合熵权法进行多指标综合分析。研究结果表明:水平管直径是影响混合性能的主导因素;通过多参数协同优化,获得了最优结构组合。相较于传统T型管,最优结构组合的综合性能提升超60%,能在8.66倍管径的短距离内实现95%的工业混合均匀度,同时将压降控制在较低水平(15.22 Pa)。最优结构组合在高达10 000 m³/h的流量下仍表现出良好的适应性,为大流量掺氢天然气管道系统的工程设计提供了理论依据和实践方案。

To address the challenges of insufficient mixing and excessive pressure loss during direct hydrogen-natural gas blending under high-flow conditions(≥600 m³/h), this study explores efficient, low-resistance mixing without auxiliary equipment through structural optimization. Based on the conventional T pipe fitting, key structural parameters—including the number of hydrogen inlets, injection angle, injection position, and horizontal pipe diameter—were selected. Numerical simulation schemes were designed using the orthogonal experimental method, and multi-criteria comprehensive analysis was conducted using the entropy weight method. Results show that the horizontal pipe diameter is the dominant factor influencing mixing performance. Through multi-parameter synergistic optimization, an optimal structural combination was obtained. Compared to the traditional T-junction, the optimal structural combination improves overall performance by over 60%, achieving 95% industrial mixing homogeneity within a short distance of 8.66 pipe diameters while maintaining a low pressure drop (15.22 Pa). The optimal structural combination exhibits excellent adaptability even at flow rates up to 10 000 m³/h, providing a theoretical basis and practical solutions for the engineering design of high-flow hydrogen-blended natural gas pipeline systems.