Abstract The direct steam generation process can contribute to increase the cost-effectiveness of line-focused solar thermal power plants. The current research focuses on the once-through mode as very promising option for large-scale commercial plants. However, the existing pool of knowledge about the steam–water flow in the horizontal receiver pipes reveals knowledge gaps. The present contribution aims to experimentally investigate the two-phase flow in the receiver pipes of the DISS test facility at the Plataforma Solar de Almeria, Spain, by an invasive measurement device for the first time. Therefore, a conductance wire-mesh sensor is employed in the low-quality evaporation section of the DISS test facility. This measurement device measures the local instantaneous void fraction that is used to describe the prevailing flow pattern under different pressures and mass flow rates. The results show slug flow, roll waves, wavy flow, and stratified-wavy flow in the horizontal receiver pipes within pressures of 30–80 bar. The probability of slug flow or large-amplitude waves decreases with higher pressures. The findings provide a valuable knowledge about the flow structure within the receiver pipes and confirm the proof of function of the wire-mesh sensor under conditions of the direct steam generation process.

中文翻译：

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单丝网传感器在直接蒸汽发生抛物线槽设施中的应用

摘要 直接蒸汽发电过程有助于提高集中式太阳能热电厂的成本效益。目前的研究集中在直流模式作为大型商业工厂的非常有前途的选择。然而，关于水平接收器管道中蒸汽-水流的现有知识库揭示了知识空白。目前的贡献旨在首次通过侵入性测量设备对西班牙 Plataforma Solar de Almeria 的 DISS 测试设施的接收器管道中的两相流进行实验研究。因此，在 DISS 测试设施的低质量蒸发部分采用了电导丝网传感器。该测量设备测量局部瞬时空隙率，用于描述不同压力和质量流量下的主要流动模式。结果显示，在 30-80 bar 的压力下，水平接收管中出现段塞流、滚波、波浪流和分层波浪流。段塞流或大振幅波的概率随压力升高而降低。这些发现提供了有关接收器管道内流动结构的宝贵知识，并证实了丝网传感器在直接蒸汽产生过程条件下的功能证明。段塞流或大振幅波的概率随压力升高而降低。这些发现提供了有关接收器管道内流动结构的宝贵知识，并证实了丝网传感器在直接蒸汽产生过程条件下的功能证明。段塞流或大振幅波的概率随压力升高而降低。这些发现提供了有关接收器管道内流动结构的宝贵知识，并证实了丝网传感器在直接蒸汽产生过程条件下的功能证明。