To address climate change issues, there has been growing interest in low-carbon H production technologies with the potential for zero-CO emissions. Non-oxidative CH pyrolysis is a promising method for producing H and solid carbon without generating CO emissions. This study presents experimental and numerical studies on non-catalytic CH pyrolysis using a vertical tube reactor (28 mm in diameter and 1800 mm in height). A three-dimensional (3D) Eulerian computational fluid dynamics (CFD) model coupled with chemical reaction and heat transfer was developed and validated against the experimentally determined axial temperature profiles and methane conversion (). The hydrodynamics, reaction kinetics, and heat transfer characteristics were investigated using the validated CFD model. The highest of 99% was achieved at 1200 °C with a gas flow rate of 0.5 LPM. Heat transfer combined with natural and forced convection was confirmed by the CFD simulation of the tubular reactor. The heat transfer coefficient in the reaction zone ranged from 43 to 46 W/m/°C. The CFD simulation served as a viable tool for examining the influence of the hydrodynamics, heat transfer, and reaction kinetics on the performance of the reactor with a given geometry and under specified operating conditions in non-catalytic CH pyrolysis.

中文翻译：

---

立管内CH4非催化热分解无CO2制氢实验与模拟

为了解决气候变化问题，人们对具有零二氧化碳排放潜力的低碳氢气生产技术越来越感兴趣。非氧化性CH热解是一种在不产生CO排放的情况下生产H和固体碳的有前途的方法。本研究介绍了使用立式管反应器（直径 28 毫米，高 1800 毫米）进行非催化 CH 热解的实验和数值研究。开发了与化学反应和传热相结合的三维 (3D) 欧拉计算流体动力学 (CFD) 模型，并根据实验确定的轴向温度分布和甲烷转化率进行了验证 ()。使用经过验证的 CFD 模型研究了流体动力学、反应动力学和传热特性。在 1200 °C、气体流速为 0.5 LPM 时达到最高 99%。管式反应器的 CFD 模拟证实了传热与自然对流和强制对流相结合。反应区的传热系数为43至46 W/m/℃。 CFD 模拟是一种可行的工具，用于检查流体动力学、传热和反应动力学对给定几何形状和非催化 CH 热解中指定操作条件下反应器性能的影响。