摘要
为了研究振翅冲击形态下水下冲击射流的频率特性,采用自由能格子Boltzmann方法对一定水深条件下的平面冲击射流流场进行了数值模拟,验证了水下冲击射流除存在稳定冲击运动形态外还存在一种新的振翅冲击运动形态。对振翅冲击射流流场内特定位置上变量的频谱分析表明:横向速度u和自由界面做周期性变化,两者频率相同;在中心轴线上,流向速度频率是横向流动速度频率的两倍。同时,与稳定冲击形态下的射流相比,振翅冲击形态下射流中心轴线速度衰减加快。
In order to study the frequency characteristics of flapping motion of submerged impinging jet,a submerged plane jet impinging onto a free surface is investigated based on the free energy lattice Boltzmann method for a given water depth.It is verified that there exists a new flapping impinging pattern,in addition to the stable impinging pattern.The PSD analyses at specific positions of flapping jet show that the lateral velocity u and surface displacement oscillate with the same frequency.And the frequency of longitudinal velocity oscillation at the jet centerline is twice of that of the transverse oscillation.Meanwhile,the mean centerline velocity decay is considerable faster than that of the stable impinging jet without flapping motion.
出处
《振动．测试与诊断》
EI
CSCD
北大核心
2013年第3期445-449,527,共5页
Journal of Vibration,Measurement & Diagnosis
基金
国家自然科学基金资助项目(10472046)
江苏高校优势学科建设工程资助项目
江苏省普通高校研究生科研创新计划资助项目(CX08B-035Z)
南京航空航天大学博士学位论文创新与创优基金资助项目(BCXJ08-01)
