Experimental and numerical investigation on the dynamic characteristics of a lab-scale transcritical CO2 loop
Experimental and numerical investigation on the dynamic characteristics of a lab-scale transcritical CO2 loop
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实验室规模跨临界 CO2 回路动态特性的实验和数值研究
DOI：
10.1016/j.enconman.2021.114384
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发表时间：
2021-10
影响因子：
10.4
通讯作者：
Yuxuan J
中科院分区：
文献类型：
--
作者：
Kaixiang Xing;Gang Xiao;Haoran Xu;Yuxuan J
超临界二氧化碳（sCO2）布雷顿循环因其高效、紧凑、耗水量少而备受关注。在sCO2循环中，跨临界CO2（tCO2）动态循环在启动、停堆和意外工况下不可避免，由于CO2在临界点附近的物理性质会发生剧烈变化，给系统设计和运行带来诸多挑战，其对系统动态特性的影响尚不清楚。在这项研究中，我们进行了实验和数值研究，以探索一个简化的tCO2回路的动态特性。数值模型的开发结合换热器，泵和背压阀与耦合的CFD和传热过程的详细考虑。通过将仿真结果与实验数据进行比较，验证了模型的有效性，得到了较小的均方根误差（<3%）。我们调查的系统响应和动态特性的案例研究，其中开发的模型具有更高的准确性，在捕捉动态特性与实验传感器相比，和环境温度的变化导致的气源压力在3.8和8.0 MPa之间的显着波动。我们还观察到，在短时间内，随着频率从20 Hz上升到50 Hz，超过1.0 MPa的压力，这大约是目标压力变化的40%。我们发现一个大的采集时间间隔可以提供稳定的结果，但可能会失去瞬态特性在操作过程中。
Supercritical carbon dioxide (sCO2) Brayton cycle attracts much attention due to its high efficiency, compactness and low water consumption. In a sCO2cycle, a transcritical CO2(tCO2) dynamic looping is unavoidable during processes of startup, shutdown and unexpected conditions, which brings many challenges in the system design and operation due to the drastic physical property change of CO2near the critical point, and its effects on the system dynamic characteristics are still not clear. In this study, we carry out experimental and numerical studies to explore the dynamic characteristics of a simplified tCO2loop. The numerical model is developed by combining heat exchangers, a pump and a back-pressure valve with a detailed consideration of the coupled CFD and heat transfer processes. We validate the model by comparing the simulation results with the experimental data and obtain a small root-mean-square error (<3%). We investigate the system response and dynamic characteristics in the case studies, where the developed model has a higher accuracy in capturing the dynamic characteristics compared with the experimental sensors, and the change of ambient temperature resulted in a significant fluctuation of gas source pressure between 3.8 and 8.0 MPa. We also observe a pressure overdose of > 1.0 MPa in a short time with the frequency rising from 20 Hz to 50 Hz, which is about 40% of the target pressure change. We find a large acquisition time gap could provide stable results but may lost transient characteristics during the operation.
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DOI：
10.1115/gt2017-64287
发表时间：
2017-06
期刊：
Sensors (Basel, Switzerland)
影响因子：
--
作者：
Junhyun Cho;Hyungki Shin;Jongjae Cho;H. Ra;C. Roh;Beomjoon Lee;Gilbong Lee;Y. Baik
通讯作者：
Junhyun Cho;Hyungki Shin;Jongjae Cho;H. Ra;C. Roh;Beomjoon Lee;Gilbong Lee;Y. Baik
变工况发动机CO2跨临界余热回收系统设计工况及运行策略分析
影响因子：
10.4
作者：
Gequn Shu;Xiaoya Li;Hua Tian;Lingfeng Shi;Xuan Wang;Guopeng Yu
通讯作者：
Guopeng Yu
DOI：
--
发表时间：
2007-04
期刊：
--
影响因子：
--
作者：
E. Lemmon;M. Huber;M. McLinden
通讯作者：
E. Lemmon;M. Huber;M. McLinden
影响因子：
9
作者：
J. Park;H. Park;J. Kwon;Tae Ho Kim;M. Kim
通讯作者：
J. Park;H. Park;J. Kwon;Tae Ho Kim;M. Kim
影响因子：
2.9
作者：
Junhyun Cho;Hyungki Shin;Jongjae Cho;Young-Seok Kang;H. Ra;C. Roh;Beomjoon Lee;Gilbong Lee;Byunghui Kim;Y. Baik
通讯作者：
Junhyun Cho;Hyungki Shin;Jongjae Cho;Young-Seok Kang;H. Ra;C. Roh;Beomjoon Lee;Gilbong Lee;Byunghui Kim;Y. Baik