基于喷嘴距可调的锥-柱形与圆柱形混合室喷射器性能对比分析  

Comparative Analysis of the Performance for Nozzle Exit Position Adjustable Conical-Cylindrical and Cylindrical Mixing Chamber Ejectors

作　　者：陈洪杰 葛敬 陈柄旭 谭丽萍 梁文良 卢苇 CHEN Hongjie;GE Jing;CHEN Bingxu;TAN Liping;LIANG Wenliang;LU Wei(School of Energy and Building Environment,Guilin University of Aerospace Technology,Guilin 541004,China;School of Chemical Engineering,Guizhou University of Engineering Science,Bijie 551700,China;Euncet Business School,Universitat Politècnica de Catalunya,Barcelona 08034,Spain;School of Mechanical Engineering,Guangxi University,Nanning 530004,China)

机构地区：[1]桂林航天工业学院能源与建筑环境学院,桂林541004 [2]贵州工程应用技术学院化学工程学院,毕节551700 [3]加泰罗尼亚理工大学商学院,巴塞罗那08034 [4]广西大学机械工程学院,南宁530004

出　　处：《真空科学与技术学报》2025年第3期236-247,共12页Chinese Journal of Vacuum Science and Technology

基　　金：广西自然科学基金项目(2022GXNSFBA035512)。

摘　　要：合理选择混合室结构是提高蒸气喷射器系统性能的重要途径。在喷嘴距和截面比可调的情况下研究了锥-柱形与圆柱形混合室喷射器的临界性能差异,并通过引入热力学完善度和熵产率模型,对这两种喷射器进行全面对比。结果表明:与圆柱形混合室喷射器在最佳喷嘴距处的情况相比,在等截面比下,锥-柱形混合室喷射器在一个合适的喷嘴距范围可获得更佳的临界喷射系数和临界冷凝压力(即实现多目标优化),其原因是采用锥-柱形混合室可减小混合流的动量损失和增大二次蒸气在混合室内的有效流通截面积,而恰当地减小锥-柱形混合室截面比时,该喷嘴距范围扩大;此外,在实验喷嘴距范围内,锥-柱形混合室喷射器的热力学完善度更具优势;降低锥-柱形混合室截面比时,可在一定的喷嘴距范围内进一步提高锥-柱形混合室喷射器的热力学完善度优势,其热力学原因是喷射器内部熵产率进一步降低。研究结果为可变几何结构喷射器临界性能的多目标优化提供新的参考思路。The rational choice of mixing chamber structure is important to improve the performance of vapor ejector systems.The critical performance differences between conical-cylindrical mixing chamber and cylindrical mixing chamber ejectors were investigated with a nozzle exit position(NXP)and area ratio(Ar)adjustable ejector,and a comprehensive comparison of the two types of ejectors was made by introducing thermodynamic perfection and entropy generation rate models.The results demonstrated that compared with the performance of the cylindrical mixing chamber ejector(CME)at the optimal nozzle exit position,the equal area ratio conical-cylindrical mixing chamber ejector(CCME)exists a NXP range where both the critical entrainment ratio and critical condensing pressure are larger(i.e.,multi-objective optimization is achieved).The mechanism of this phenomenon is the use of CCM can reduce the momentum loss of the mixed flow and increase the effective flow cross-sectional area of the secondary vapor.The NXP range can be widened by appropriately reducing the Ar of the CCME.Besides,the thermodynamic perfection of the CCME is more advantageous in the range of the experimental NXP than CME.When reducing the Ar of the CCME,the thermodynamic perfection of the CCME can be further improved within a certain range of NXP,and the thermodynamic reason is that the entropy production rate inside the CCME is further reduced.The results provide a new idea for the multi-objective optimization of the critical performance for variable geometry ejectors.

关 键 词：蒸气喷射器 混合室 临界性能 多目标优化 熵产率 热力学完善度 

分 类 号：TK114[动力工程及工程热物理—热能工程]