Evaluation of air compressibility effects on the performance of fixed OWC wave energy converters using CFD modelling
Evaluation of air compressibility effects on the performance of fixed OWC wave energy converters using CFD modelling
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DOI：
10.1016/j.renene.2017.12.027
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发表时间：
2018-04
期刊：
影响因子：
8.7
通讯作者：
I. Simonetti;L. Cappietti;H. Elsafti;H. Oumeraci
中科院分区：
文献类型：
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作者：
I. Simonetti;L. Cappietti;H. Elsafti;H. Oumeraci
本研究提出了一个评估的错误所引起的忽略空气压缩性的影响，在模拟振荡水柱（OWC）波能转换器。验证开源软件包OpenFOAM®中的可压缩两相CFD模型，然后将其用于模拟从海底分离的固定OWC装置。对在全尺寸（1：1）和四个较小尺寸（1：50、1：25、1：10和1：5）下模拟装置所获得的结果进行比较分析，以评估与空气压缩性相关的尺寸效应。实际上，对于模拟中考虑的空气压力水平（在模型比例1：50下高达350 Pa），忽略空气压缩性的影响导致OWC室中的空气压力和随后的空气体积通量的高估高达约15%，但捕获宽度比的高估小于10%。这种高估随着压力水平的增加而增加。结果进行了分析，在无量纲参数和一个新的参数，强烈相关的可压缩效应，提出并用于提供广义方程提供校正因子。
This study presents an evaluation of the error induced by neglecting the effect of air compressibility in modelling Oscillating Water Column (OWC) wave energy converters. A compressible two phases CFD model in the open-source software package OpenFOAM®is validated and then used to simulate a fixed OWC device, detached from the sea bottom. A comparative analysis of the results obtained by simulating the device at full-scale (1:1) and at four smaller scales (1:50, 1:25, 1:10 and 1:5) is performed in order to assess the scale effects associated with air compressibility. Indeed, for the air pressure levels considered in the simulations (up to 350 Pa at model scale 1:50), the effect of neglecting the air compressibility results in an overestimation up to about 15% for the air pressure in the OWC chamber and the subsequent air volume flux, but less than 10% for the capture width ratio. This overestimation increases with increasing pressure level. Results are analysed in terms of dimensionless parameters and a new parameter, strongly related to the compressible effects, is proposed and used to provide generalized equations delivering correction factors.