发动机热源条件对小规模CO2发电系统的影响
Ligeng Li1, Hua Tian1, Xin Lin1
1State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China.
Fundamental research
|June 18, 2025
概括
这项研究展示了一种可回收发动机废热的二氧化碳动力系统,从而减少燃料使用和排放. 该系统实现了高功率输出和效率,在动态条件下显示稳定的运行.
科学领域:
- 热力学是一种热力学.
- 废热回收系统 废热回收系统
- 整合可再生能源的整合
背景情况:
- 发动机废热意味着大量的能量损失,有助于燃料消耗和排放.
- 波动的发动机运行条件挑战了废热回收系统的一致性性能.
- 开发有效的系统来捕获和利用这种废热对于提高整体能源效率至关重要.
研究的目的:
- 实验评估一个小规模 (10千瓦) 的二氧化碳发电系统,用于从发动机中回收废热.
- 评估关键部件的性能,包括轮膨胀器和印刷电路换热器,在各种发动机条件下.
- 确定系统的整体稳定状态和过渡性能及其提高发动机效率的潜力.
主要方法:
- 建造和测试一台10千瓦的二氧化碳发电系统,配备定制的轮膨胀器和印刷电路换热器.
- 在一系列的发动机运行条件下进行的实验性性能测试 (不同质量流速,温度和压力).
- 对单个组件和集成系统的稳定状态和过渡性性能数据的分析.
主要成果:
- 轮扩展器在动态条件下表现出稳定的运行,最大发电功率和效率分别达到11.55千瓦和58.92%.
- 印刷电路换热器有效地平衡了传热和压力下降,保持了排气气体压力下降低于4kPa.
- 在特定的发动机条件下,集成系统实现了最大净功率10.57千瓦和6.59%的热效率,提高了6.3%的发动机车热效率.
结论:
- 开发的二氧化碳发电系统有效地回收发动机废热,提高整体能源效率并减少排放.
- 该系统的组件能够稳定有效地运行,即使在动态的发动机条件下.
- 这项技术为提高内燃机的热效率提供了可行的解决方案.
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