识别蒸汽注入滚动压缩机的性能和损耗,以及R1234ze(E)
George Meramveliotakis1,2, George Kosmadakis1, Sotirios Karellas2
1Thermal Hydraulics and Multiphase Flow Laboratory, National Center for Scientific Research Demokritos, Agia Paraskevi, 15341, Greece.
Open research Europe
|August 30, 2023
概括
热中的蒸汽注入因吸气压力下降而在高起重时显著降低性能. 一个新的模型显示,高摩擦和层流是影响效率的关键问题.
科学领域:
- 热力学是一种热力学.
- 机械工程 机械工程
- 制冷系统 制冷系统
背景情况:
- 热对于高效的加热和冷却至关重要.
- 蒸汽注入滚动压缩机可以提高热的性能.
- R1234ze(E) 是一种用于环保应用的新兴制冷剂.
研究的目的:
- 调查使用R1234ze(E) 的蒸汽注入滚动压缩机热的性能.
- 确定高温电梯性能显著下降的原因.
- 开发和验证一个改进的半经验模型,用于压缩机性能分析.
主要方法:
- 在广泛的温度范围内对水对水热进行实验测试.
- 开发一个包含蒸汽注入的半实证压缩机模型.
- 实施了一种新的吸气压力下降模型,考虑了层状和流流程.
- 对实验数据的模型验证和R1234ze(E) 的参数调整.
主要成果:
- 热的性能在30K以上的升降器中大幅下降,COP低于2.
- 最大的第二法效率仅达到28%.
- 由于摩擦和潜在的层状流量而导致的高吸压下降被确定为主要的损失机制.
- 开发的模型准确地捕捉了性能退化,与标准模型不同.
结论:
- 吸气压力下降是限制热蒸汽注入滚动压缩机效率的关键因素,特别是在R1234ze(E).
- 这种新型建模方法可以更好地了解压缩机性能不足.
- 优化吸管设计以减轻压力下降对于提高热效率至关重要.
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