在寒冷环境条件下通过工作流体混合提高s-CO2布雷顿电源周期效率
Paul Tafur-Escanta1, Luis Coco-Enríquez2, Robert Valencia-Chapi1
1Facultad de Ingeniería en Ciencias Aplicadas, Universidad Técnica del Norte, Ibarra 100150, Ecuador.
Entropy (Basel, Switzerland)
|July 29, 2025
概括
将低临界温度添加剂添加到超临界二氧化碳 (s-CO2) 中,可以在寒冷的气候下提高再压缩布雷顿循环 (RBC) 的效率. 与甲和四甲混合物显示出显著的性能增长.
科学领域:
- 热力学是一种热力学.
- 发电工程 发电工程 发电工程
- 材料科学 材料科学 材料科学
背景情况:
- 超临界二氧化碳 (s-CO2) 布雷顿循环提供高效率,但由于接近临界点,在寒冷的气候下降.
- 格陵兰,俄罗斯,加拿大,斯堪的纳维亚和阿拉斯加等寒冷地区为s-CO2电力系统带来了运营挑战.
- 重压布雷顿循环 (RBC) 架构是发电的重点,但其在零度以下温度下的性能需要优化.
研究的目的:
- 在零度以下环境温度下使用基于二氧化碳的二元混合物来研究再压缩布雷顿循环 (RBC) 的性能.
- 评估低临界温度添加剂对s-CO2电力系统在寒冷气候中的热力学效率和运行稳定的影响.
- 确定最佳的工作流体组成和系统配置,以提高在寒冷环境中的性能.
主要方法:
- 模拟了RBC循环的热力学性能,使用基于CO2的二元混合物与甲 (CH4),四甲 (CF4),三化 (NF3) 和 (Kr) 等添加剂.
- 分析了低于零度的环境温度对循环效率和组件性能的影响,特别是高温回收器 (HTR).
- 进行了比较性能量分析,以评估纯二氧化碳与混合物循环的能量利用效率.
主要成果:
- 与甲和四甲混合的基于二氧化碳的混合物,与纯二氧化碳相比,其热效率提高了高达10个百分点.
- 含NF3的混合物在中度寒冷条件下表现良好,而基于Kr的混合物提供了一致的,尽管适度的,效率增长.
- 高温回收器 (HTR) 在低压缩机入口温度下成为关键的限制部件,需要最佳电导率 (UA) 分配和基于混合物的循环的尺寸增加.
结论:
- 定制的工作流体,特别是基于二氧化碳的二元混合物,可以在寒冷的气候下显著提高s-CO2动力系统的热力学性能和运行稳定性.
- 像CH4和CF4这样的添加剂的战略性使用提供了一个可行的途径,以克服s-CO2布雷顿循环在零下环境中的效率退化.
- 优化回收器设计,特别是HTR,对于最大限度地利用在寒冷条件下RBC架构中基于混合物的工作流体的好处至关重要.
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