文献类型：期刊文献

英文题名：Simulation research on phase change and jet characteristics of supercritical CO2 in confined space fracturing device

作者：An, Zhoujian Yang, Fan Ding, Yong Du, Xiaoze Zhang, Dong Fu, Jian

第一作者：An, Zhoujian

通信作者：An, ZJ[1];Ding, Y[2]

机构：[1]Lanzhou Univ Technol, Sch Energy & Power Engn, Lanzhou 730050, Peoples R China;[2]Guizhou Inst Technol, Sch Aerosp Engn, Guiyang 550025, Peoples R China

第一机构：Lanzhou Univ Technol, Sch Energy & Power Engn, Lanzhou 730050, Peoples R China

通信机构：corresponding author), Lanzhou Univ Technol, Sch Energy & Power Engn, Lanzhou 730050, Peoples R China;corresponding author), Guizhou Inst Technol, Sch Aerosp Engn, Guiyang 550025, Peoples R China.|贵州理工学院;

年份：2026

卷号：238

外文期刊名：JOURNAL OF SUPERCRITICAL FLUIDS

收录：;EI(收录号：20262721049616);Scopus(收录号：2-s2.0-105043701429);WOS:【SCI-EXPANDED(收录号:WOS:001820938600001)】；

基金：This work was financially supported by the Guizhou Provincial Major Scientific and Technological Program (XKBF (2025) 031) ; the Guizhou Science and Technology Innovation Leading Talent Workstation (KXJZ (2025) 024) ; the Guizhou Provincial Basic Research Program (Natural Science) (MS [2025] 189) ; the China Postdoctoral Science Foundation (2025M770576) ; the Wuwei City Major Science and Technology Special Projects (WW25A03ZDQ002) ; the Science and Technology Project of Gansu province (23JRRA1663) ; the Doctoral Research Funds of Lanzhou University of Technology (061907) ; the Young Faculty Interdisciplinary Research Cultivation Program of Lanzhou University of Technology (LUTXKJC25019) and the Red Willow Excellent Youth Project of Lanzhou University of Technology.

语种：英文

外文关键词：Supercritical CO 2; Rock-breaking devices; Phase change; Jet characteristics

摘要：Supercritical CO2 (scCO2) rock breaking devices have seen preliminary engineering applications, yet existing studies focus mainly on post-breaking outcomes, overlooking pre-breaking flow field evolution - critical for fracturing performance. This study conducts transient simulations of pressurization and jetting in scCO2 phase change fracturing, employing a user-defined real gas model (UDRGM) and user-defined functions (UDFs) to characterize CO2 thermophysical properties. The multi-stage flow evolution within the expansion tube and supersonic jet dynamics are systematically analyzed. Results show that during the phase change pressure boosting stage, buoyancy forces drive a triangular axial distribution of scCO2 volume fraction along the tube axis, increasing with axial distance. Within 30 ms, intense phase change and natural convection occur, with axial velocity peaking at 19 m/s. After 80 ms, most of the fluid converts into scCO2 with a sharp pressure surge. During the jet induced fracturing stage, the initial jet velocity exhibits an inverted "N" -shaped variation. The non-uniform exit back-pressure distribution induced by asymmetric filling in the jet region, combined with asymmetric shock wave-boundary layer interactions and internal non-uniformities of the expansion tube, causes the Mach disk to tilt. Injection pressure exerts a stronger influence on jet characteristics than temperature, with the maximum volume-averaged velocity increasing by approximately 11.31% as the initial injection condition rises. After 1.90 ms, impact energy gradually dissipates and internal flow resistance increases, causing the volume-averaged velocity to decline. This study elucidates flow field evolution during scCO2 pressurization and jetting, offering theoretical support for optimizing phase-change fracturing processes and selecting engineering parameters.