Flow Field Analysis and Structure Improvement of Generator Unit Based on STAR-CCM+

The design requirements of high performance and lightweight of generator unit put forward higher requirements for its cooling system. The generator unit has good cooling performance, which can ensure the generator unit to work at the best temperature and ensure the stable and reliable operation of generator unit. In order to evaluate the cooling performance of a generator unit, based on the CFD analysis method, the fluid analysis software STAR-CCM+ was used to conduct the flow field analysis of generator unit, and the structural improvement design was put forward according to the flow field analysis results. The results showed that the air from the cylinder head of the original structure of the generator unit was directly blown to the bottom of oil tank, there was no air flow on the surface of the muffler, which was a cooling risk for generator unit. The cooling performance of generator was improved by adding cylinder head air guide cover and muffler ventilation cover. The surface velocity at the bottom of oil tank was significantly reduced, and the cooling air quantity at the muffler was increased from 28.91 g/s to 135.78 g/s. The average air velocity on the muffler surface was about 4.04 m/s. The experimental temperature results show that when the generator unit operates at rated power for 120 min, the temperature at the bottom of oil tank and the top of motor at the state of improved generator unit was reduced by 38 ℃ and 17 ℃. The research results can provide theoretical guidance for the evaluation of cooling performance and structural improvement of generator units.