改善COP和热回收的新方法在牛奶加工应用的超临界CO2制冷系统中
Prosenjit Singha1, Chayan Das2, Mani Sankar Dasgupta2
1Department of Mechanical Engineering, BITS Pilani, Pilani, 333031, India. prosenjit.singha@pilani.bits-pilani.ac.in.
Scientific reports
|February 14, 2025
概括
低温和并行压缩显著提高了二氧化碳制冷系统在炎热的气候中的性能. 蒸发式冷却集成为牛奶加工应用提供了大幅节省能源和减少用水量.
科学领域:
- 热力学和制冷工程 热力学和制冷工程
- 可持续能源系统 可持续能源系统
背景情况:
- 超冷却 (后冷却) 提高了二氧化碳超临界制冷系统的性能系数 (COP),特别是在炎热的气候下.
- 现有的系统往往缺乏先进的次冷却或高效的气体冷却,限制了它们的性能和能源效率.
研究的目的:
- 研究使用集成机械次冷却 (IMS) 和专用机械次冷却 (DMS) 带有蒸发冷却的二氧化碳超临界制冷系统的性能提升.
- 为了评估这些安排在一个双蒸发器平行压缩系统,为牛奶加工应用量身定制.
- 将拟议的系统与使用闪光气体绕道的基线系统进行比较.
主要方法:
- 实现一个双蒸发器并行压缩系统,结合IMS和DMS的冷却策略.
- 集成一个重力供应的蒸发器,用于蒸发式冷却气体冷却器.
- 使用印度浦那特定位置气象数据进行性能评估,重点关注COP和热回收.
- 与没有次冷却但具有闪光气体绕道的基线系统进行比较分析.
主要成果:
- 当加冷与并行压缩相结合时,观察到显著的COP改善.
- 使用蒸发式冷却和并行压缩的系统比基线闪光气体绕道系统实现了62.3%的COP改进.
- 采用蒸发式冷却导致热回收潜力大大减少.
- 与有间接蒸发冷却的快速气体绕道系统相比,水消耗减少了45.6%.
结论:
- 将次冷却技术与并行压缩相结合,为温暖气候中的二氧化碳超临界系统提供了相当大的COP收益.
- 拟议的蒸发式冷却系统显示出在牛奶加工中节省能源和水的巨大潜力.
- 在实施蒸发式冷却时,COP增强和热回收潜力之间存在权衡.
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