Influence of flow distribution on the thermal performance of dual-media thermocline energy storage systems
Influence of flow distribution on the thermal performance of dual-media thermocline energy storage systems
复制标题
流量分布对双介质温跃层储能系统热性能的影响
DOI：
10.1016/j.apenergy.2014.12.024
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发表时间：
2015-03
期刊：
影响因子：
11.2
通讯作者：
段远源
中科院分区：
文献类型：
--
作者：
王乐天;杨震;段远源
双介质熔盐温跃层热能储存（TES）系统可用于维持聚光太阳能发电（CSP）工厂的恒定发电量，而不受天气变化的影响，其成本低于传统的双罐熔盐储存系统。流量分布是影响热性能的关键参数，但在以往的研究中很少考虑双介质TES系统。分析了盐岩双介质温跃层TES池进出口流量分布对热性能的影响。采用径向分量来表征流场分布，并采用双温模型来研究温跃层水池的热性能。该模型首先与文献中的实验数据进行了验证，然后用于研究不同流量分布的温跃层蓄热槽的放电过程。结果表明，即使在入口处有较大的流动阻塞（面积的80%），流量分配对双介质储罐的可用能量输出的影响也很有限（变化<3%）。事实上，流动的不均匀性减小了温跃层的厚度并略微增加了可用能量输出，而顶部出口处的不均匀性略微降低了输出。熵产生分析，包括从扩散和间隙传热的影响，进行进一步解释这些现象。间隙热传递是导致放电熵产生的主要原因。流动的不均匀性也被发现，以减少熵产生。
Dual-media molten-salt thermocline thermal energy storage (TES) systems can be used to maintain constant power production at Concentrated Solar Power (CSP) plants independent of weather changes at costs less than that of traditional two-tank molten-salt storage systems. The flow distribution is a critical parameter affecting the thermal performance but has rarely been considered for dual-media TES systems in previous studies. This study analyzes the influence of the flow distributions at the inlet and outlet of a salt-rock dual-media thermocline TES tank on the thermal performance. The flow distribution is characterized by radial component, and a two-temperature model is used to investigate the thermal performance of the thermocline tank. The model is first validated against experiment data available in the literature and then used to study the discharge process of the thermocline thermal storage tank for various flow distributions. The results show that even with a large (80% of the area) flow blockage at the inlet, the flow distribution has only a limited influence on the useable energy output (<3% change) of the dual-media storage tank. In fact, the flow non-uniformities reduce the thickness of the thermocline layer and slightly increase the useable energy output, whereas non-uniformities at the top outlet slightly decrease the output. An entropy generation analysis, including the effects from diffusion and interstitial heat transfer, is performed to further explain these phenomena. The interstitial heat transfer is found to be the main cause for the entropy generation in the discharge. Flow non-uniformities are also found to reduce the entropy generation.
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影响因子：
6.7
作者：
Zhen Yang;S. Garimella
通讯作者：
Zhen Yang;S. Garimella
影响因子：
5.2
作者：
Y. Zurigat;Pedro R. Liche;A. Ghajar
通讯作者：
Y. Zurigat;Pedro R. Liche;A. Ghajar
DOI：
10.1016/j.applthermaleng.2010.12.019
发表时间：
2011-08
期刊：
--
影响因子：
--
作者：
A. Karim
通讯作者：
A. Karim
DOI：
10.1016/j.ijheatmasstransfer.2009.03.005
发表时间：
2009-07
影响因子：
5.2
作者：
Jianfeng Lu;J. Ding
通讯作者：
Jianfeng Lu;J. Ding
DOI：
10.1115/1.1464123
发表时间：
2001-04
影响因子：
2.3
作者：
J. Pacheco;S. Showalter;W. J. Kolb
通讯作者：
J. Pacheco;S. Showalter;W. J. Kolb