自激振荡脉冲超临界二氧化碳射流冲击频率变化规律  

Impact frequency variation of self-excited oscillation pulsed supercritical carbon dioxide jets

作　　者：沈荷莲 刘勇[1,2] 魏建平 邱黎明[3] 李海超 邓玉洁 SHEN Helian;LIU Yong;WEI Jianping;QIU Liming;LI Haichao;DENG Yujie(State Key Laboratory Cultivation Base for Gas Geology and Gas Control,Henan Polytechnic University,Jiaozuo 454000,China;State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization,Jiaozuo 454000,China;School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]河南理工大学瓦斯地质与瓦斯治理国家重点实验室培育基地,河南焦作454000 [2]煤炭安全生产与清洁高效利用省部共建协同创新中心,河南焦作454000 [3]北京科技大学土木与资源工程学院,北京100083

出　　处：《石油勘探与开发》2023年第5期1097-1104,共8页Petroleum Exploration and Development

基　　金：国家自然科学基金(52174170,51974109);中国工程科技发展战略河南研究院战略咨询研究项目(2022HENZDB03);河南理工大学基本科研业务费专项资助项目(NSFRF220205)。

摘　　要：为了得到自激振荡脉冲超临界二氧化碳(SC-CO_(2))射流谐振破煤适用冲击频率,采用大涡模拟研究了自激振荡脉冲SC-CO_(2)射流的形成及发展过程,分析了射流频率在喷嘴内部和自由流场中的变化规律,研究了射流轴向位置和振荡腔长度对射流冲击频率的影响规律,并研制了射流冲击频率测试装置,通过实验验证了数值模拟结论。研究表明,自激振荡脉冲SC-CO_(2)射流在喷嘴内部和自由流场中的频率并不相同。在喷嘴内部,流体经扰动形成的频率相同,且喷嘴出口处射流频率与喷嘴内部频率保持一致。在自由流场中,由于CO_(2)的可压缩性,射流压力、速度等参数具有明显的波动。该特征使自激振荡脉冲SC-CO_(2)射流冲击频率随射流的发展沿轴向逐渐减小。通过改变振荡腔长度,可以改变自激振荡脉冲SC-CO_(2)射流喷嘴内部频率从而实现自由流场中射流冲击频率的调节。In order to obtain the impact frequency of resonant coal breaking by self-excited oscillation pulsed supercritical carbon dioxide(SC-CO_(2))jet,large eddy simulation was used to analyze the formation and development process of self-excited oscillation pulsed SC-CO_(2)jet,the variation of jet impact frequency in the nozzle and the free flow field,and the variation of jet impact frequency at different positions in the jet axis and under different cavity lengths.The test device of jet impact frequency was developed,and experiments were performed to verify the conclusions of the numerical simulations.The results show that the frequency of the self-excited oscillation pulsed SC-CO_(2)jet is different in the nozzle and the free flow field.In the nozzle,the frequency generated by the fluid disturbance is the same,and the jet impact frequency at the exit of the nozzle is consistent with that inside the nozzle.In the free flow field,due to the compressibility of CO_(2),the pressure,velocity and other parameters of SC-CO_(2)jets have obvious fluctuation patterns.This feature causes the impact frequency of the self-excited oscillation pulsed SC-CO_(2)jet to decrease gradually in the axis.Changing the cavity length allows the adjustment of the jet impact frequency in the free flow field by affecting the disturbance frequency of the self-excited oscillation pulsed SC-CO_(2)jet inside the nozzle.

关 键 词：自激振荡脉冲超临界二氧化碳射流 谐振破煤 射流冲击频率 振荡腔长度 

分 类 号：TE37[石油与天然气工程—油气田开发工程]