Effects of windbreak mesh on thermo-flow characteristics of air-cooled steam condenser under windy conditions
Abstract Ambient wind has adverse impacts on the thermal-flow characteristics of air-cooled steam condenser (ACSC). A windbreak mesh is arranged below the ACSC platform and outside the ACSC steel supporting structure to improve ACSC performance, and its effects are numerically investigated. The windbreak mesh in a rectangle-type configuration improves the volumetric effectiveness of almost all periphery fans because of the protection effect. It also increases the volumetric effectiveness of most inner fans at +X wind direction, while it has little effect on inner fans at +Y wind direction because main buildings locating upstream of the ACSC weaken the protection effect of windbreak mesh. In addition, the windbreak mesh has the greatest effect on inlet air temperatures of windward fans at +X wind direction because of the alleviation of reversed flow, while the inlet air temperatures of periphery fans locating in Row 1 and Row 8 decrease obviously at +Y wind direction as a result of hot air recirculation mitigated by windbreak mesh. Obviously, the total ACSC heat transfer effectiveness is improved by windbreak mesh under windy conditions. Compared with grid-type and cross-type configurations, the windbreak mesh in rectangle-type configuration can protect the periphery fans to avoid suffering ambient wind to the greatest extent, and it consequently shows the best performance in general.