基于PIV可视化的蓄冷板外围流场优化研究

Research on flow field optimization of cold storage plate periphery based on PIV visualization

蓄冷板冷量释放受周围气流流动情况的影响。为研究气流流速、蓄冷板迎风面形状等因素对蓄冷板外围气流流动的影响,搭建基于粒子示踪技术(Particle Image Velocimetry,PIV)的蓄冷板外围流场可视化试验平台,研究不同迎风面形状、进风流量以及摆放间距对蓄冷板表面平均风速、气流分布等参数的影响。试验结果表明,随着进风流量的增大,蓄冷板外表面和间隙内的空气流速不均匀性逐步增大;在单蓄冷板试验中,蓄冷板的迎风面形状影响表面平均风速的大小和分布,且进风流量越大,影响作用越明显,在小流量Q_(0)和中流量3Q_(0)工况下,采用矩形迎风面的蓄冷板能达到最优的对流效果,在大流量5Q_(0)工况下,采用圆角迎风面的蓄冷板能达到最优的对流效果;在双蓄冷板试验中,蓄冷板间隙内的表面平均风速随进风流量的增大呈先上升后下降的趋势,随着蓄冷板间距的增加呈增大的趋势,得到对流效果最优的参数组合为双圆角蓄冷板、进风流量3Q_(0)、摆放间距4 cm,其表面平均风速为1.82 m/s。该研究可为蓄冷板冷量释放效率的优化提供参考依据。

Cold storage energy release is affected by the air flow around it.In this study,an experimental platform based on Particle Image Velocimetry was developed to investigate the influence of factors such as air flow rate,windward surface shape,and placement spacing on the flow field of cold storage plate periphery.Consequently,the air velocity inhomogeneity in outer surface and the gap of cold storage plate increased with the increase in inlet air flow rate.In the test of single cold storage plate,the windward surface shape affected the air velocity of surface of cold storage plate,and the greater the inlet air flow,the more significant the effect.The cold storage plate with rectangular windward plane achieved optimal convection effect under air flow rate Q_(0) and 3Q_(0),and the cold storage plate with circular windward plane under air flow rate 5Q_(0).In the test of double cold storage plate,the average air velocity of the gap rose first and then decreased with increase in inlet air flow,and rose with increase in the placement spacing.The best combination of parameters were obtained when the optimal convection effect was double cold storage plate with circular windward plane,air flow rate was 3Q_(0) and placement spacing was 4 cm,which achieved average air velocity of surface of 1.82 m/s.The results will provide a reference for optimization of release efficiency of cold storage energy.