轴流风机中雷诺应力与应变滞后涡黏模型的PIV实验  

PIV experiment of Reynolds stress-strain lag eddy viscosity model in axial fan

作　　者：贾永霞[1] 姜楠[1] 

机构地区：[1]天津大学机械工程学院力学系,天津300072

出　　处：《航空动力学报》2011年第10期2323-2329,共7页Journal of Aerospace Power

基　　金：国家自然科学基金重点项目"尾迹引起的边层旁路转捩机理及其控制的实验研究"(10832001);面上项目"基于瞬态三维层析技术的湍流相干结构特征及其控制机理的实验研究"(10872145);中国科学院力学研究所非线性国家重点实验室对外开放课题;天津大学科研创新基金

摘　　要：采用粒子成像测速(PIV)技术,精细测量了低速轴流风机内部叶片60%跨度处压力面与吸力面的切向和轴向速度,以及风机出口径向平面的切向和径向速度,基于叶片的周缘速度和叶片弦长的雷诺数为370000.应用周期相位平均技术分析雷诺剪切应力与平均速度剪切应变的时空演化过程,并应用互相关技术研究了两者之间的相位关系.结果表明雷诺剪切应力与平均速度剪切应变的极值发生在不同时空相位,存在相位滞后.这一现象广泛存在于三维非平衡复杂湍流中,显然,工业领域广泛应用的线性k-ε模型具有一定的缺陷,应考虑雷诺应力张量与平均速度应变张量之间的时空滞后现象,从而得到符合物理规律的计算结果.因此,雷诺应力张量与平均速度应变张量滞后的涡黏模型将成为一个很有发展前景的封闭模型,来更加精准地预测工业领域中广泛存在的非平衡复杂湍流.Time-resolved particle image velocimetry（PIV）was used to investigate the flow at suction and pressure sides of 60% span of blades,as well as the flow at the radial plane of fan outlet in a low-speed forward-swept axial fan with three blades at Reynolds number of 370 000,based on the tip speed and the blade chord.The data was processed to yield the time evolution of Reynolds shear stress and averaged velocity shear strain using the phase-averaged method,and the spatial phase relationship between the both was investigated through the correlation technology.The phase lag between Reynolds shear stress and averaged velocity shear strain was found,which phenomenon widely existed in the three-dimensional non-equilibrium turbulence.So the studied Reynolds stress-strain lag eddy viscosity model could be considered as a promising closure for improving the state-of-the-art industrial computational fluid dynamics by accounting for non-equilibrium effects in comparison with a classical linear k-ε model,which is widely applied in the industry.

关 键 词：轴流风机 叶片 雷诺应力 速度应变 滞后涡黏模型 

分 类 号：O357.5[理学—流体力学]