海上多孔介质通道内氢气换热与正仲氢转化的耦合特性

Coupling characteristics of hydrogen heat transfer and normal-parahydrogen conversion in offshore porous media channels

在我国“碳达峰、碳中和”的战略目标下,风电和化石能源制氢技术正不断发展,利用海上风电资源或天然气制备氢气,并通过储运技术送到氢能源市场,为解决海上风电并网和消纳的难题、促进深海天然气资源的低碳发展提供了可行的思路,因此研究应用于浮式氢气液化工艺系统的绕管式换热器海上适应性具有重要意义。本文基于多自由度的晃荡平台,搭建了浮式多孔介质通道内压降测试实验装置;基于多孔介质模型、正-仲氢转化和氢流动换热理论模型,建立了多孔介质通道内耦合正-仲氢转化的流动换热数值模型。通过实验与数值模拟相结合的方法,分析海况和水平条件下多孔介质换热通道的性能变化。研究结果表明,填充催化剂的绕管式换热器多孔介质通道内压降明显,温降不明显,管内仲氢含量增加;随着氢气流量的增加,传热系数逐渐增大,而出口仲氢的含量逐渐降低;海况对海上多孔介质换热通道的压降和传热特性影响较小。

Under our country's strategic goal of carbon peaking and carbon neutrality,wind power and fossil energy hydrogen production technologies are constantly developing.Use offshore wind power resources or natural gas to produce hydrogen and send it to the hydrogen energy market through storage and transportation technology,which provides a feasible idea for solving the problems of offshore wind power grid integration and consumption and promotes the low-carbon development of deep-sea natural gas resources.Therefore,it is of great significance to study the offshore adaptability of the spiral wound heat exchanger applied in the floating hydrogen liquefaction process system.Based on the multi-degreeof-freedom sloshing platform,an experimental device for pressure drop testing in floating porous media channels was built.Based on the porous media model,the theoretical model of normal-parahydrogen conversion and hydrogen flow heat transfer,a numerical model of flow heat transfer coupled with normal-parahydrogen conversion in porous media channels was established.The performance changes of porous media heat exchange channels under sea and horizontal conditions were analyzed by a combination of experiments and numerical simulations.The research results showed that the pressure drop in the porous medium channel of the spiral wound heat exchanger filled with catalyst was obvious,the temperature drop was not obvious,and the parahydrogen content in the tube increased.With the increase of hydrogen flow,the heat transfer coefficient increased gradually,while the content of parahydrogen in the outlet decreased gradually.Sea conditions had little effect on the pressure drop and heat transfer characteristics of offshore porous media heat exchange channels.