The horizontal axis turbine is one of the most promising energy extractors for tidal stream energy utilization. However, there is no widely accepted model for describing the wake structure of a tidal stream turbine. Besides, the flow velocity variation in wakes is accompanied by energy transformation and has hardly been investigated to date. In this paper, a brief review of existing laboratory tidal stream turbine experiments is first presented, followed by a discussion about the controlling variables that includes cross-comparisons between different results from physical laboratory tests. Theoretical derivation and experimental data analysis are conducted to enable a better understanding of the energy transformation and wake development processes, and tidal stream energy extraction. It has been found that part of the flow kinetic energy has been converted into potential energy before reaching the rotor, commonly used power coefficients are not equivalent when quantifying energy extraction, and it is possible to reconstruct turbine wakes using 3 independent data-based parameters.

水平轴涡轮机是潮汐能利用中最有前途的能量提取器之一。但是，目前尚无广泛描述潮汐流涡轮机尾流结构的模型。此外，尾流中的流速变化会伴随能量转化，迄今为止尚未进行研究。本文首先简要介绍了现有的实验室潮汐水轮机实验，然后讨论了控制变量，其中包括物理实验室测试的不同结果之间的交叉比较。进行了理论推导和实验数据分析，以使人们更好地了解能量转换和尾流发展过程以及潮汐流能量提取。