可调式与固定式喷射器内动量交换的相似性与非平衡特性研究  

Research on Similarity and Non-equilibrium Characteristics of Momentum Exchange in Adjustable and Stationary Ejectors

作　　者：杨勇[1] 王宁 韩沛时 任笑彤 李熠桥 张琨 沈胜强[1] YANG Yong;WANG Ning;HAN Peishi;REN Xiaotong;LI Yiqiao;ZHANG Kun;SHEN Shengqiang(Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education,School of Energy and Power Engineering,Dalian University of Technology,Dalian 116024,China;College of Locomotive and Rolling stock Engineering,Dalian Jiaotong University,Dalian 116028,China;School of Ocean and Civil Engineering,Dalian Ocean University,Dalian 116023,China)

机构地区：[1]大连理工大学能源与动力学院海洋能源利用与节能教育部重点实验室,大连116024 [2]大连交通大学机车车辆工程学院,大连116028 [3]大连海洋大学海洋与土木工程学院,大连116023

出　　处：《工程热物理学报》2025年第4期1067-1077,共11页Journal of Engineering Thermophysics

基　　金：国家自然科学基金重点项目(No.51936002);大连市科技创新基金项目(No.2020JJ26SN063)。

摘　　要：基于气体动力学方法,构建了喷射器变工况调节特性分析模型,结合关键截面流动与压力特性分析模型、动量交换评价模型,对比分析了固定式与可调式喷射器内部的动量交换、混合升压特性随喷射器压力、温度、速度、流量的变化规律,揭示了喷射器变工况调节的临界特征、相似特征、尺度效应。研究结果显示,喷射器临界模态下,第三极限状态与第一极限或第二极限状态同时到来;混合室进、出口压差随工作流量增大而逐渐减小,混合室出口流速随之增大,扩压室内激波升压能力有显著提升,但能量耗散增大,混合室动量效率随之降低;喷射器的工作特性具有显著的尺度关联特征,设计工况下喷射系数、动量交换系数、动量交换效率均为最优值,偏离最优结构后,动量交换系数有显著的降低;进口过热度的提升对有限边界层尺度的动量交换具有一定促进作用。Based on aerodynamic method,a performance calculation model for variable operating conditions of ejector is constructed,combined with analytical model for flow and pressure characteris-tics and evaluation model for momentum exchange,the momentum exchanging,mixing and pressure lifting characteristics inside adjustable and stationary ejectors are compared with varying pressure,temperature,velocity and flow rate.The critical characteristics,similarity features and scale effects are researched.The research results show that,in critical mode of ejector,the third critical mode always achieves combined with the first or second critical mode.The pressure difference between inlet and outlet of mixing chamber gradually decreases with increasing of primary flow rate,mean-while the outlet velocity of mixing chamber increases accordingly,and shock wave boosting ability in discharging chamber is significantly improved,but energy dissipation increases with momentum efficiency of mixing chamber decreases accordingly.The operating characteristics of ejector have significant scale dependent features.Under design conditions,the entrainment ratio,momentum ex-change coefficient and momentum exchange efficiency all achieve optimal values.When departuring from the optimal structure,momentum exchange coefficient significantly decreases.The increasing in import superheat has certain promoting effect on momentum exchange at finite boundary layer scale.

关 键 词：可调式喷射器 动量交换系数 边界层 过热度 相似性 

分 类 号：TS255.3[轻工技术与工程—农产品加工及贮藏工程]