Multi-objective optimisation for wind resistant air-cooled condenser operation

Abstract

• Multi-objective optimisation is performed for air-cooled condenser wind mitigation. • Perimeter screens, cruciform screens and walkways are simultaneously investigated. • Both thermal effectiveness and dynamic fan blade loading are considered. • General guidelines on optimal walkway and screen configuration are provided. • Both thermal effectiveness and dynamic blade loading can be noticeably improved. A multi-objective optimisation using a genetic algorithm combined with a surrogate modelling approach was used to identify optimal wind mitigation solutions for 3 × 6 cell air-cooled condenser (ACC), typical of a 100 MW thermal power plant. General guidelines on how to optimally combine a cruciform screen, perimeter screen and solid walkway were identified by finding the Pareto-optimal front considering both overall ACC thermal performance and maximum fan blade dynamic loading. The combination of a cruciform screen and a walkway is always recommended. The cruciform screen should have a height of 0.35 ≤ H cs / H p ≤ 0.50 and a solidity of 0.75 ≤ α cs ≤ 1.0. The width of the walkway should be within 0.30 ≤ L ww / d f ≤ 0.50. A perimeter screen is only recommended if dynamic blade loading is expected to be a significant issue. For a permanent perimeter screen, the solidity should be α ps ≈ 0.4 with a screen height between 0.6 ≤ H ps / H p ≤ 1.0. A mitigation solution within these ranges was able to improve the ACC average thermal effectiveness by up to 19 % under high wind conditions and reduce the blade loading by 22 %, thus resulting in a robust wind effect mitigation solution and ultimately greater annual condenser reliability.