基于压电风扇位移的周期性运动规律，采用动网格技术对存在横流时双压电风扇激励的三维非定常流动和传热进行数值模拟，获得了双压电风扇两种布置方式（并列和串列）在同相和反相振动方式下的涡系结构和表面换热特征。研究结果表明，双压电风扇振动相位对于对流换热性能有较大的影响，对于并列布置的双压电风扇，反相振动时在双风扇振动包络区下游的换热能力优于同相振动情形；对于串列布置的双压电风扇，反相振动时在相邻风扇之间的区域对流换热显著低于同相振动情形。
A numerical investigation is performed to explore the 3D unsteady flow features and heat transfer performance induced by dual vertically-oriented piezoelectric fans in the presence of cross flow. The numerical simulations are conducted by using dynamic meshing scheme in combination with the periodic movement law of the displacement of the vibrating fan. The vortical and thermal features with dual piezoelectric fans are obtained for two dual fans arrangements (face-to-face and edge-to-edge) at in-phase and out-of-phase vibrating conditions. The results show that the vibrating phase of dual fans has an obvious influence on convective heat transfer performance. For the dual fans arranged in the face-to-face mode, the convective heat transfer downstream the fan-tip vibration envelope under the out-of-phase situation is higher than that under the in-phase situation. For the dual fans arranged in the edge-to-edge mode, the convective heat transfer in the region between two adjacent fans under the out-of-phase situation is significantly less than that under the in-phase situation.
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