热声发动机中的交变流动换热器特性研究  

Characterization of Oscillating Flow Heat Exchanger of the Thermoacoustic Engine

作　　者：王海涛 罗靖 张丽敏[1] 孙岩雷 陈远航 常德鹏 陈燕燕[1] 余国瑶[1] 罗二仓[1,2] WANG Haitao;LUO Jing;ZHANG Limin;SUN Yanlei;CHEN Yuanhang;CHANG Depeng;CHEN Yanyan;YU Guoyao;LUO Ercang(Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry,Chinese Academy of Science,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院理化技术研究所低温工程学重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《西安交通大学学报》2023年第5期97-108,共12页Journal of Xi'an Jiaotong University

基　　金：国家重点研发计划资助项目(2021YFC28026003);国家自然科学基金资助项目(51876214)。

摘　　要：为阐明热声发动机交变流动换热器内基本换热与阻力特性,以10 kW直线热管耦合自由活塞斯特林发电机的发动机核心为例,对三维模型进行等效,分别利用Sage一维和CFD二维模型两种方法,对交变流动换热单元在额定工况下的沿程基本状态参数、时均能量的分布特征进行计算并比较。结果表明:Sage一维模型中的换热分布特征及换热总量均与CFD二维模型计算结果相近,即Sage一维模型可以较好地捕捉换热器内的瞬态与时均特征;同时,Sage一维模型对换热器界面的突变截面损失则与CFD二维模型计算差异较大,可利用CFD二维模型的阻力计算结果,提出采用有效压降与有效速度获得突变截面处的局部阻力系数修正,并添加修正因子后代入Sage一维模型,可使Sage一维模型的阻力特性与CFD二维模型的阻力特性基本吻合。所得热声热机中换热器特性规律及分析方法同样可用于指导其他热声热机的相关研究与工程设计,具有一定的普适性。In this paper,core engine components of a 10 kW free piston Stirling generator with a linear heat pipe coupled is taken as an example to illustrate the basic heat transfer and resistance characteristics of the oscillating flow heat exchanger of a thermoacoustic engine.By equating a 3D model,the Sage 1D model and CFD 2D model are adopted respectively to characterize the distribution of basic state parameters and time-averaged energy of the alternating flow heat transfer unit under rated operating conditions.The results show that the Sage 1D model is similar to the CFD 2D model in terms of the heat transfer distribution characteristics and the total amount of heat transfer calculated.The Sage 1D model can better capture the transient and time-averaged characteristics in the heat exchanger.However,the sudden cross-sectional losses at the heat exchanger interface calculated with the Sage 1D model deviate greatly from those calculated by the CFD 2D model.As a result,a local drag correction coefficient is proposed based on the resistance values calculated with the CFD 2D model,and according to the effective pressure drop and effective velocity at the abrupt cross-section.After the correction coefficient is used in the Sage model,the drag characteristics obtained using this model basically match those acquired using the CFD 2D model.The resultant heat exchanger characteristics and analysis method can be used to guide the research and engineering design of other thermoacoustic heat exchangers,exhibiting their general applicability.

关 键 词：热声热机 交变流动换热器 换热特性 阻力特性 局部阻力修正 

分 类 号：TK123[动力工程及工程热物理—工程热物理]