This paper presents a relative comparison of the impact of cruciform screens, perimeter screens and walkways on 3 × 6 cell forced draft air-cooled condenser's (ACC) thermal performance and dynamic fan blade loading under windy conditions. Numerical simulations were carried out for the three mitigation measures at two fan platform heights, four wind speeds and three wind directions. The results indicate that walkways are a robust solution to ACC wind effects and offer benefits in terms of thermal performance and dynamic blade loading under all wind conditions considered. Cruciform screens offered the most effective mitigation of wind-related thermal performance deterioration under certain wind conditions, but the impact of these screens is sensitive to the wind direction. The dynamic blade loading impact of cruciform screens is variable, and these screens are not recommended for dynamic blade loading mitigation. Perimeter screens offered the most effective mitigation of dynamic blade loading and were particularly effective at high wind speeds but often exacted a penalty in terms of thermal performance at moderate to low wind speeds. The results of this study indicate that a correctly configured wind mitigation system, potentially consisting of more than one individual mechanism, could help improve thermal performance and simultaneously reduce dynamic blade loading under windy conditions resulting in a robust, wind resistant condenser.

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Ambient wind has a negative effect on mechanical forced-draft direct air-cooled steam condenser (ACC) fan volumetric performance, and increases dynamic fan blade loading. Investigating these effects directly using on-site measurement or numerical analysis is complicated, and most previous work has focused on only one effect at the expense of the other. In this study, fan axial velocity inflow uniformity is identified as a single metric offering the potential to holistically qualify ACC fan operation under windy conditions. A 3 × 6 fan cell ACC was modelled with CFD using a blade element theory-based fan model, and clear relationships between the fan inflow uniformity index and both fan volumetric performance and dynamic blade loading were observed in the results. The same relationships were observed in on-site test data collected at a single ACC fan, thus validating the numerical results. The uniformity index can be used in both numerical and experimental work as a means of investigating both fan volumetric performance and dynamic blade loading with less computational and measurement complexity; it also offers a potentially useful means of quantifying the severity of fan operating conditions, to assist with more reliable case-specific fan design and selection.