基于正交试验的蒸汽喷射器喷嘴结构优化  

Optimization of Steam Ejector Nozzle Structure Based on Orthogonal Test

作　　者：秦汉时 方凯跃 高洪辉 操正清 杨雪龙 QIN Hanshi;FANG Kaiyue;GAO Honghui;CAO Zhengqing;YANG Xuelong(Collaborative Innovation Center for Emissions Trading System Co-constructed by the Province and Ministry,Hubei University of Economics,Wuhan 430205,China;School of Low Carbon Economics,Hubei University of Economics,Wuhan 430205,China;School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China;College of Metrology and Measurement Engineering,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]湖北经济学院碳排放权交易省部共建协同创新中心,武汉430205 [2]湖北经济学院低碳经济学院,武汉430205 [3]武汉大学动力与机械学院,武汉430072 [4]中国计量大学计量测试工程学院,杭州310018

出　　处：《真空科学与技术学报》2024年第7期612-618,共7页Chinese Journal of Vacuum Science and Technology

摘　　要：采用计算流体动力学(CFD)技术结合正交试验方法对蒸汽喷射器喷嘴的结构参数进行优化以提高效率。以同时优化喷嘴收缩段形状曲线、喉管长径比以及扩散段角度为目标,将喷射系数(ER)和临界背压(CBP)作为性能指标,建立L9(33)正交表,制定9组试验方案,共77个案例。采用湿蒸汽模型计算蒸汽流动过程中的相变现象。通过极差分析得出了三个参数的重要性顺序并对整体以及喷嘴处的流场进行分析。结果表明:影响蒸汽喷射器工作蒸汽流量、喷射系数和临界背压的主要因素为喷嘴收缩段形状曲线;影响被吸蒸汽流量主要因素为扩散段角度和喷嘴收缩段形状曲线;二次曲线、较小的喉管长径比和较大的扩张段角度有利于降低喷嘴阻力,提高工作蒸汽流量;湿蒸汽模型考虑了喷射器的冷凝现象,对喷射器内部流动的计算更为真实。Computational fluid dynamics(CFD)techniques combined with orthogonal test methods were used to optimize the structural parameters of steam ejector nozzles to improve efficiency.With the objective of simultaneously optimizing the shape curve of the nozzle shrinkage section,the throat length,and the angle of the diffusion section,and taking the entrainment rate(ER)and critical back pressure(CBP)as the performance indexes,the L9(33)orthogonal table was established to develop nine sets of test protocols with 77 cases.A wet steam model was used to calculate the phase change phenomena during steam flow.The importance of three parameters was determined through range analysis,and the overall flow field and nozzle flow field were analyzed.The results show that the main factor affecting the working steam flow rate,entrainment rate,and critical back pressure of the steam ejector is the shape curve of the nozzle contraction section;quadratic curves,shorter throat lengths,and larger diffusion section angles contribute to lower nozzle resistance and higher working steam flow rates;the wet steam model takes into account the condensation phenomenon of the ejector and provides a more realistic calculation of the flow inside the ejector.

关 键 词：喷射器 湿蒸汽 喷嘴 正交实验 优化 计算流体动力学 

分 类 号：TK172[动力工程及工程热物理—热能工程]