圆形肋柱通道强化换热流动机理实验研究  

Experimental investigation on flow mechanism driving heat transfer enhancement in a channel with circular pin fins

作　　者：段敬添 张科[1,2] 徐进 雷蒋[1,2] 武俊梅 DUAN Jingtian;ZHANG Ke;XU Jin;LEI Jiang;WU Junmei(State Key Laboratory for Strength and Vibration of Mechanical Structures,School of Aerospace,Xi’an Jiaotong University,Xi’an 710049,China;Shaanxi Key Laboratory of Environment and Control for Flight Vehicle,School of Aerospace,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学航天航空学院机械结构强度与振动国家重点实验室,西安710049 [2]西安交通大学航天航空学院陕西省先进飞行器服役环境与控制重点实验室,西安710049

出　　处：《实验流体力学》2021年第4期10-18,共9页Journal of Experiments in Fluid Mechanics

基　　金：陕西省自然科学基金(2019JM-382)。

摘　　要：圆形肋柱广泛应用于涡轮叶片内部尾缘强化换热通道。针对圆形肋柱通道强化换热流动机理开展了实验研究,利用PIV技术得到相同雷诺数Re(1.0×10^(4)或2.0×10^(4))下通道中心面的流场分布,并与稳态液晶测温实验得到的通道端壁努塞尔数Nu分布进行对比。结果表明:对于圆形肋柱通道,肋柱下游尾迹区后横向速度脉动强度分布和端壁Nu分布相似,而流动充分发展后,小尺度脉动增强,湍流动能(Turbulent Kinetic Energy,TKE)和Nu的分布都非常均匀;随着Re的增大,横向速度脉动强度和端壁传热强化都明显下降,说明圆形肋柱下游涡脱落带来的强烈横向速度脉动是当地换热增强的主要原因,而其下游小尺度的速度脉动会使局部换热更加均匀。Circular pin fins are commonly used in the internal cooling channel of the turbine blade.This paper mainly investigated experimentally the flow mechanism driving heat transfer enhancement in a wide channel with staggered circular pin fins.The flow field in the mid-plane of the channel was measured using Particle Image Velocimetry(PIV).Nusselt number distributions on the endwall was obtained by means of Thermochromic Liquid Crystal(TLC)in the same geometry under the same Reynolds number(1.0×10^(4)or 2.0×10^(4)).Results indicate that downstream of circular pins the distribution of vrms is similar to that of Nu.However,when the flow is developed,smaller scale fluctuation increases,and the distributions of turbulent kinetic energy(Kt)and Nu are more uniform.The heat transfer enhancement and cross-stream velocity fluctuation are decreased when Re increases.It is concluded that intense lateral velocity fluctuation induced by vortex shedding is the main flow mechanism driving local heat transfer enhancement.Small scale fluctuation makes local heat transfer uniform.

关 键 词：圆形肋柱 强化换热 流动特性 交错排布 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]