Steam Turbine Hall Ventilation at Vasilikos Power Plant

A CFD model was constructed for the simulation of the steam turbine hall of Vasilikos Power Station in Cyprus, in order to present and prove the adequacy of the ventilation system design. The project was performed for J&P – AVAX S.A.

The 3D geometry was extracted directly from available 3D CAD files, after the un-necessary details were deleted. A tet-dominated mesh of 3.6M cells was created, due to the complexity of the geometry. Inflation layers were positioned around the major energy-dissipating equipment (steam turbines and generators). The air flow rates and temperature supplied from the AHUs and extracted by the roof fans were prescribed according to the performance of the equipment and were implemented as boundary conditions. The thermal loads due to solar radiation and mechanical equipment operation were prescribed at the appropriate solid surfaces. Buoyancy was taken into consideration into the physical model, as thermal stratification occurs due to the temperature difference and the large height of the building.

The temperature difference in-height is clearly shown in Figs. 2 and 3, where a thermal plume is evident over the steam turbines. The air velocity is not uniform inside the hall, as indicated by Fig. 4, due to the complex arrangement and significant number of supply vents, extraction fans and free vents, arranged over the building’s envelope. The result, is also a significant variation in Mean Age of Air, shown in Fig. 5.