主管部门: 中国航天科技集团有限公司
主办单位: 中国航天空气动力技术研究院
中国宇航学会
中国宇航出版有限责任公司

留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

FD-21风洞Ma=10高超声速推进试验技术探索

卢洪波 陈星 曾宪政 陈勇富 孙日明 文帅 戴武昊 谌君谋 毕志献 金熠

卢洪波, 陈星, 曾宪政, 陈勇富, 孙日明, 文帅, 戴武昊, 谌君谋, 毕志献, 金熠. FD-21风洞Ma=10高超声速推进试验技术探索[J]. 气体物理, 2022, 7(2): 1-12. doi: 10.19527/j.cnki.2096-1642.0926
引用本文: 卢洪波, 陈星, 曾宪政, 陈勇富, 孙日明, 文帅, 戴武昊, 谌君谋, 毕志献, 金熠. FD-21风洞Ma=10高超声速推进试验技术探索[J]. 气体物理, 2022, 7(2): 1-12. doi: 10.19527/j.cnki.2096-1642.0926
LU Hong-bo, CHEN Xing, ZENG Xian-zheng, CHEN Yong-fu, SUN Ri-ming, WEN Shuai, DAI Wu-hao, SHEN Jun-mou, BI Zhi-xian, JIN Yi. Exploration of Experimental Techniques on Ma=10 Scramjets in FD-21 High Enthalpy Shock Tunnel[J]. PHYSICS OF GASES, 2022, 7(2): 1-12. doi: 10.19527/j.cnki.2096-1642.0926
Citation: LU Hong-bo, CHEN Xing, ZENG Xian-zheng, CHEN Yong-fu, SUN Ri-ming, WEN Shuai, DAI Wu-hao, SHEN Jun-mou, BI Zhi-xian, JIN Yi. Exploration of Experimental Techniques on Ma=10 Scramjets in FD-21 High Enthalpy Shock Tunnel[J]. PHYSICS OF GASES, 2022, 7(2): 1-12. doi: 10.19527/j.cnki.2096-1642.0926

FD-21风洞Ma=10高超声速推进试验技术探索

doi: 10.19527/j.cnki.2096-1642.0926
基金项目: 

国家重点研发计划资助项目 2019YFA0405204

国家自然科学基金 11772316

详细信息
    作者简介:

    卢洪波(1985-)男, 高工, 博士, 主要研究高Mach数吸气式推进试验技术.E-mail: finlhb_0605@163.com

    通讯作者:

    陈星(1979-)男, 研究员, 主要研究激波风洞技术及气动热测量技术.E-mail: chenxing0234@sina.com

  • 中图分类号: V211.751

Exploration of Experimental Techniques on Ma=10 Scramjets in FD-21 High Enthalpy Shock Tunnel

  • 摘要: 针对Mach数8以上(Ma>8)冲压发动机地面试验能力不足问题,基于FD-21高能脉冲风洞,开展了吸气式推进试验技术探索,提升了FD-21风洞的重活塞驱动能力,获得了总压18.66 MPa、总温3 950 K、Ma=9.62、静压436.6 Pa、速度3 km/s的高焓大动压模拟流场,同时发展了高时间分辨率吸收光谱测量技术和基于重模型自由飞原理的发动机推阻测量方法.在此基础上,设计了弯曲激波压缩二元发动机,构建了燃料在线供应与喷注控制、模型悬挂与瞬态释放及相关测量一体的试验系统,在所建立的Ma=9.62风洞模拟环境中进行了集成验证试验,定量测得了有/无氢气射流与空气/氮气超声速气流作用下二元发动机的壁面压力、吸收光谱峰值吸收率、轴向力等数据,并利用纹影观测到了进气道唇口与燃烧室部位的波系特征.多次试验所得的壁面压力、峰值吸收率、轴向力随时间变化曲线均存在2 ms以上的平台,表明二元发动机建立了准定常流动.冷热态及氮气对照组对应的壁面压力分布、峰值吸收率、轴向力等数据呈现出了明显不同,且二者规律近似一致,一方面说明所建立的模拟流场、燃烧诊断技术、发动机推阻测量技术是有效的,另一方面也表明二元发动机实现了点火燃烧、获得有效热功转换,为后续相关研究奠定了良好的基础.

     

  • 图  1  FD-21高能脉冲风洞主体结构

    Figure  1.  Structure of FD-21 high enthalpy shock tunnel

    图  2  入射激波运动Mach数在激波管内的变化

    Figure  2.  Incident shock Mach number along shock tube axial location

    图  3  距离激波管末端1.17 m(S9)处壁面压力变化

    Figure  3.  Time variation of wall pressure located at 1.17 m(S9)from the shock tube downstream end

    图  4  距离激波管末端1.17 m(S9), 0.02 m(S10)处壁面压力变化

    Figure  4.  Time variation of wall pressure located at 1.17 m(S9) and 0.02 m(S10) from shock tube downstream end

    图  5  弯曲激波压缩二元发动机模型(2DSM)

    Figure  5.  Two-dimensional curved shock compression scramjet model(2DSM)

    图  6  基于自由飞原理的二元发动机推阻测量结构(2DSM-A)

    Figure  6.  Experimental setup of 2DSM-A

    图  7  微小位移光学追踪方法

    Figure  7.  A nonlinear method to extract the tiny displacement from image

    图  8  二元发动机的TDLAS光路布置及其保护结构模型(2DSM-B)

    Figure  8.  Four light-path configurations with protecting structure of TDLAS on 2DSM-B

    图  9  FD-21风洞燃料喷注前置时序图

    Figure  9.  Fuel injection time sequence in FD-21 shock tunnel

    图  10  有无氢气喷注下二元发动机各测点压力随时间变化

    Figure  10.  Time variation of wall pressure on 2DSM for the shots with hydrogen injection and no injection

    图  11  不同工况下发动机沿程壁面静压分布

    Figure  11.  Streamwise pressure distributions on 2DSM wall for different shots

    图  12  氢气喷注当量比近似一致、不同试验介质对应的TDLAS测得的V1峰值吸收率随时间变化

    Figure  12.  Peak absorbance of different test-gas shots from TDLAS at the approximately identical equivalence ratio

    图  13  二元发动机进气道与燃烧室纹影图

    Figure  13.  Flow pattern at inlet and flow pattern on combustor of 2DSM from high speed schlieren

    图  14  氢气喷注时发动机轴向加速度随时间变化(2021车次, ϕ=0.416)

    Figure  14.  Time variation of axial acceleration and wall pressure on 2DSM-A (No. 2021, ϕ=0.416)

    表  1  FD-21风洞总压18.66 MPa、总温3 950 K模拟条件下名义Ma=10喷管出口参数

    Table  1.   Freestream parameters of the simulated Ma=10 conditions in FD-21 shock tunnel

    P/Pa T/K Tvib/K U/(m/s) Ma CN2, ∞/(%) CO2, ∞/(%) CNO, ∞/(%) CO, ∞/(%)
    436.6 257.5 1 478 3 000 9.62 74.32 20.80 4.85 0.03
    下载: 导出CSV

    表  2  基于二元发动机模型的验证试验概况

    Table  2.   Test information of 2DSM

    Shot No. test gas model equivalence
    ratio
    measure methods
    2018 air 2DSM-A 0 piezoresistive sensors
    2019 air 2DSM-A 0
    2020 air 2DSM-A 0 piezoresistive sensors, high-speed photography, accelerometer
    2021 air 2DSM-A 0.416
    2022 air 2DSM-A 0.358
    2023 air 2DSM-B 0.346 piezoresistive sensors, high-speed Schlieren, accelerometer, TDLAS
    2024 air 2DSM-B 0.360
    2025 nitrogen 2DSM-B 0.347
    2026 air 2DSM-B 0
    下载: 导出CSV

    表  3  TDLAS测得的温度与水蒸气(H2O)分压(2023车次, ϕ=0.346)

    Table  3.   Time-averaged temperature and partial pressure of water vapor from TDLAS(shot No. 2023, ϕ=0.346)

    light-path time-averaged temperature/K time-averaged partial pressure of H2O/Pa
    V1 1 215.8 203.7
    V2 1 194.8 207.9
    H1 1 195.6 174.7
    H2 1 193.4 196.1
    mean value 1 199.9 195.6
    max error 1.3% 10.7%
    下载: 导出CSV

    表  4  基于自由飞原理测得的不同工况下二元矩形发动机模型的轴向力数据

    Table  4.   Axial force on 2DSM-A and 2DSM-B measured by large-scale free-flight techniques for different shots

    Shot No. test gas equivalence ratio model axial accelera-tion/(m/s2) dimensionless aixal force dimensionless inner net force between hot and cold shots
    2020 air 0 2DSM-A 14.08 65.70 0
    2021 air 0.416 2DSM-A 16.80 91.17 -25.47
    2022 air 0.358 2DSM-A 11.44 52.39 13.31
    2023 air 0.346 2DSM-B 21.28 105.44 14.16
    2024 air 0.360 2DSM-B 21.82 113.88 5.72
    2025 nitrogen 0.347 2DSM-B 24.34 119.60 0
    下载: 导出CSV
  • [1] 俞刚, 范学军. 超声速燃烧与高超声速推进[J]. 力学进展, 2013, 43(5): 449-471. https://www.cnki.com.cn/Article/CJFDTOTAL-LXJZ201305001.htm

    Yu G, Fan X J. Supersonic combustion and hypersonic propulsion[J]. Advances in Mechanics, 2013, 43(5): 449-471(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-LXJZ201305001.htm
    [2] Curran E T. Scramjet engines: the first forty years[J]. Journal of Propulsion and Power, 2001, 17(6): 1138-1148. doi: 10.2514/2.5875
    [3] Gu S, Olivier H. Capabilities and limitations of existing hypersonic facilities[J]. Progress in Aerospace Sciences, 2020, 113: 100607. doi: 10.1016/j.paerosci.2020.100607
    [4] Stalker R J, Paull A, Mee D J, et al. Scramjets and shock tunnels-the Queensland experience[J]. Progress in Aerospace Sciences, 2005, 41(6): 471-513. doi: 10.1016/j.paerosci.2005.08.002
    [5] Paull A, Stalker R J, Mee D J. Experiments on supersonic combustion ramjet propulsion in a shock tunnel[J]. Journal of Fluid Mechanics, 1995, 296: 159-183. doi: 10.1017/S0022112095002096
    [6] Robinson M J, Mee D J, Paull A. Scramjet lift, thrust and pitching-moment characteristics measured in a shock tunnel[J]. Journal of Propulsion and Power, 2006, 22(1): 85-95. doi: 10.2514/1.15978
    [7] McGilvray M, Kirchhartz R, Jazra T. Comparison of Mach 10 scramjet measurements from different impulse facilities[J]. AIAA Journal, 2010, 48(8): 1647-1651. doi: 10.2514/1.J050025
    [8] Doherty L J. An experimental investigation of an airframe integrated three-dimensional scramjet engine at a Mach 10 flight condition[D]. Brisbane: The University of Que-ensland, 2014.
    [9] Barth J. Mixing and combustion enhancement in a Mach 12 shape-transitioning scramjet engine[D]. Brisbane: The University of Queensland, 2014.
    [10] Vanyai T. Experimental investigation of a 3D thermal compression scramjet using advanced optical techniques[D]. Brisbane: The University of Queensland, 2018.
    [11] Denman Z J, Chan W Y, Brieschenk S, et al. Ignition experiments of hydrocarbons in a Mach 8 shape-transitioning scramjet engine[J]. Journal of Propulsion and Power, 2016, 32(6): 1462-1471. doi: 10.2514/1.B36099
    [12] Denman Z J, Wheatley V, Smart M K, et al. Supersonic combustion of hydrocarbons in a shape-transitioning hypersonic engine[J]. Proceedings of the Combustion Institute, 2017, 36(2): 2883-2891. doi: 10.1016/j.proci.2016.08.081
    [13] Vanyai T, Grieve S, Street O, et al. Fundamental scramjet combustion experiments using hydrocarbon fuel[J]. Journal of Propulsion and Power, 2019, 35(5): 953-963. doi: 10.2514/1.B37472
    [14] Hiraiwa T, Ito K, Sato S, et al. Recent progress in scramjet/combined cycle engines at JAXA, Kakuda space center[J]. Acta Astronautica, 2008, 63(5/6): 565-574.
    [15] Takahashi M, Sunami T, Tanno H, et al. Performance characteristics of a scramjet engine at Mach 10 to 15 flight condition[R]. AIAA 2005-3350, 2005.
    [16] Takahashi M, Komuro T, Sato K, et al. Performance characteristics of scramjet engine with different combustor shapes at hypervelocity condition over Mach 10 flight[R]. AIAA 2007-5395, 2007.
    [17] Sunami T, Itoh K, Satoh K, et al. Mach 8 ground tests of the hypermixer scramjet for HyShot-Ⅳ flight experiment[R]. AIAA 2006-8062, 2006.
    [18] Schramm J M, Sunami T, Ito K, et al. Experimental investigation of supersonic combustion in the HIEST and HEG free piston shock tunnels[R]. AIAA 2010-7122, 2010.
    [19] Marie T, Hideyuki T, Tomoyuki K. Free-flight force measurement technique for scramjet powered vehicle in shock tunnel[C]. Proceedings of the 32nd International Symposium on Shock Waves (ISSW322019), 2019.
    [20] Hannemann K, Schramm J M, Wagner A, et al. A closely coupled experimental and numerical approach for hypersonic and high enthalpy flow investigations utilising the HEG shock tunnel and the DLR TAU code[R]. RTO-EN-AVT-186, 2010.
    [21] Schramm J M, Karl S, Hannemann K, et al. Ground testing of the Hyshot Ⅱ scramjet configuration in HEG[R]. AIAA 2008-2547, 2008.
    [22] Laurence S J, Karl S, Schramm M J, et al. Transient fluid-combustion phenomena in a model scramjet[J]. Journal of Fluid Mechanics, 2013, 722: 85-120. doi: 10.1017/jfm.2013.56
    [23] Laurence S J, Lieber D, Schramm J M, et al. Incipient thermal choking and stable shock-train formation in the heat-release region of a scramjet combustor. Part Ⅰ: shock-tunnel experiments[J]. Combustion and Flame, 2015, 162(4): 921-931. doi: 10.1016/j.combustflame.2014.09.016
    [24] Larsson J, Laurence S, Bermejo-Moreno I, et al. Incipi-ent thermal choking and stable shock-train formation in the heat-release region of a scramjet combustor. Part Ⅱ: large eddy simulations[J]. Combustion and Flame, 2015, 162(4): 907-920. doi: 10.1016/j.combustflame.2014.09.017
    [25] Hannemann K, Schramm J M, Karl S, et al. Free flight testing of a scramjet engine in a large scale shock tunnel[R]. AIAA 2015-3608, 2015.
    [26] Hannemann K, Schramm J M, Karl S, et al. Enhance-ment of free flight force measurement technique for scramjet engine shock tunnel testing[R]. AIAA 2017-2235, 2017.
    [27] Karl S, Schramm J M, Hannemann K. Post-test analysis of the LAPCAT-Ⅱ subscale scramjet[J]. CEAS Space Journal, 2020, 12(2): 385-395.
    [28] 王培勇, 陈明, 邢菲, 等. Hyshot超燃冲压发动机的CFD数值模拟[J]. 航空动力学报, 2014, 29(5): 1020-1028. https://www.cnki.com.cn/Article/CJFDTOTAL-HKDI201405005.htm

    Wang P Y, Chen M, Xing F, et al. CFD numerical simulation of Hyshot scramjet[J]. Journal of Aerospace Power, 2014, 29(5): 1020-1028(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-HKDI201405005.htm
    [29] 周建兴, 汪颖. 高马赫数超燃冲压发动机性能数值研究[J]. 推进技术, 2014, 35(4): 433-441. https://www.cnki.com.cn/Article/CJFDTOTAL-TJJS201404001.htm

    Zhou J X, Wang Y. Numerical investigation on performance of a high Mach number scramjet[J]. Journal of Propulsion Technology, 2014, 35(4): 433-441(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-TJJS201404001.htm
    [30] 张时空, 李江, 黄志伟, 等. 高马赫数来流超燃冲压发动机燃烧流场分析[J]. 宇航学报, 2017, 38(1): 80-88. https://www.cnki.com.cn/Article/CJFDTOTAL-YHXB201701011.htm

    Zhang S K, Li J, Huang Z W, et al. Combustion flow field analysis of a scramjet engine at high Mach number[J]. Journal of Astronautics, 2017, 38(1): 80-88(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-YHXB201701011.htm
    [31] 钟萍, 孙宗祥, 傅邦杰, 等. 高超声速流动模拟需求及地面试验能力分析[J]. 飞航导弹, 2012(3): 20-26. https://www.cnki.com.cn/Article/CJFDTOTAL-FHDD201203006.htm

    Zhong P, Sun Z X, Fu B J, et al. Simulation requirements of hypersonic flow and ground test ability[J]. Aerodynamic Missile Journal, 2012(3): 20-26(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-FHDD201203006.htm
    [32] 姚轩宇. JF-12激波风洞超燃冲压发动机实验及污染气体效应影响研究[D]. 北京: 中国科学院大学, 2015.

    Yao X Y. Experimental study on the scramjet in JF-12 shock tunnel and its vitiation effects[D]. Beijing: University of Chinese Academy of Sciences, 2015(in Chinese).
    [33] 姚轩宇, 王春, 喻江, 等. JF12激波风洞高Mach数超燃冲压发动机实验研究[J]. 气体物理, 2019, 4(5): 25-31. doi: 10.19527/j.cnki.2096-1642.0788

    Yao X Y, Wang C, Yu J, et al. High Mach number scramjet engine tests in JF12 shock tunnel[J]. Physics of gases, 2019, 4(5): 25-31(in Chinese). doi: 10.19527/j.cnki.2096-1642.0788
    [34] 刘云峰. 斜爆轰发动机理论与验证[C]. 第十九届全国激波与激波管学术会议. 厦门: CAAA, 2020.

    Liu Y F. Theory and verification of oblique detonation engine[C]. The 19th National Shock Wave Conference. Xiamen: CAAA, 2020(in Chinese).
    [35] Ma K F, Zhang Z J, Liu Y F, et al. Aerodynamic principles of shock-induced combustion ramjet engines[J]. Aerospace Science and Technology, 2020, 103: 105901. doi: 10.1016/j.ast.2020.105901
    [36] 翟小飞, 张扣立, 白菡尘, 等. 激波加热超声速燃烧室直连式试验台喷管中的化学非平衡流动[J]. 空气动力学学报, 2020, 38(2): 268-273. https://www.cnki.com.cn/Article/CJFDTOTAL-KQDX202002008.htm

    Zhai X F, Zhang K L, Bai H C, et al. Chemical nonequilibrium flow in nozzle of a supersonic combustor direct-connected test bed with shock heating[J]. Acta Aerodynamica Sinica, 2020, 38(2): 268-273(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-KQDX202002008.htm
    [37] 欧阳浩, 邓维鑫, 邢建文, 等. 飞行Ma10条件燃烧特性试验研究[C]. 第十九届全国激波与激波管学术会议. 厦门: CAAA, 2020.

    Ouyang H, Deng W X, Xing J W, et al. Experimental study on supersonic combustion at flight Mach number of 10[C]. The 19th National Shock Wave Conference. Xiamen: CAAA, 2020(in Chinese).
    [38] 吴里银, 孔小平, 李贤, 等. 马赫数10超燃冲压发动机激波风洞实验研究[J]. 推进技术, 2021, 42(12): 2818-2825. https://www.cnki.com.cn/Article/CJFDTOTAL-TJJS202112019.htm

    Wu L G, Kong X P, Li X, et al. Shock tunnel experiments of a Ma10 scramjet[J]. Journal of Propulsion Technology, 2021, 42(12): 2818-2825(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-TJJS202112019.htm
    [39] 卢洪波, 陈星, 谌君谋, 等. 新建高焓激波风洞Ma=8飞行模拟条件的实现与超燃实验[J]. 气体物理, 2019, 4(5): 13-24. doi: 10.19527/j.cnki.2096-1642.0782

    Lu H B, Chen X, Shen J M, et al. Flight condition achievement of Mach number 8 in a new shock tunnel of CAAA and its scramjet experimental investigation[J]. Physics of Gases, 2019, 4(5): 13-24(in Chinese). doi: 10.19527/j.cnki.2096-1642.0782
    [40] Lu H B, Chen X, Chen L, et al. Preliminary commissioning of hydrogen supersonic combustion in FD-21 free piston driven shock tunnel[C]. 32nd International Symposium on Shock Waves (ISSW32), OR-03-248, Singa-pore, 2019.
    [41] 陈勇富, 卢洪波, 文帅, 等. 基于图像识别的高焓激波风洞发动机推阻测量技术[C]. 第十九届全国激波与激波管学术会议. 厦门: CAAA, 2020.

    Chen Y F, Lu H B, Wen S, et al. Scramjet thrust measurement techniques of image-detecting in a high enthalpy shock tunnel[C]. The 19th National Shock Wave Confer-ence. Xiamen: CAAA, 2020(in Chinese).
    [42] 卢洪波. 高焓激波风洞燃烧空气动力学试验技术的探索与进展[C]. 第十九届全国激波与激波管学术会议大会邀请报告. 厦门: CAAA, 2020.

    Lu H B. Exploration and development of aerodynamic experimental techniques coupled with combustion in a high enthalpy shock tunnel[C]. The 19th National Shock Wave Conference. Xiamen: CAAA, 2020(in Chinese).
    [43] 陈星, 谌君谋, 毕志献, 等. 自由活塞高焓脉冲风洞发展历程及试验能力综述[J]. 实验流体力学, 2019, 33(4): 65-80. https://www.cnki.com.cn/Article/CJFDTOTAL-LTLC201904010.htm

    Chen X, Shen J M, Bi Z X, et al. Review on the development of the free-piston high enthalpy impulse wind tunnel and its testing capacities[J]. Journal of Experiments in Fluid Mechanics, 2019, 33(4): 65-80(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-LTLC201904010.htm
    [44] Park C. Review of chemical-kinetic problems of future NASA mission, I: earth entries[J]. Journal of Thermophysics and Heat Transfer, 1993, 7(3): 385-398. doi: 10.2514/3.431
    [45] 张堃元. 基于弯曲激波压缩系统的高超声速进气道反设计研究进展[J]. 航空学报, 2015, 36(1): 274-288. https://www.cnki.com.cn/Article/CJFDTOTAL-HKXB201501021.htm

    Zhang K Y. Research progress of hypersonic inlet reverse design based on curved shock compression system[J]. Acta Aeronautica et Astronautica Sinica, 2015, 36(1): 274-288(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-HKXB201501021.htm
    [46] Lu F, Marren D. Advanced hypersonic test facilities[M]. Reston: American Institute of Aeronautics and Astronautics, 2002: 198.
    [47] 吴颖川, 贺元元, 贺伟, 等. 吸气式高超声速飞行器机体推进一体化技术研究进展[J]. 航空学报, 2015, 36(1): 245-260. https://www.cnki.com.cn/Article/CJFDTOTAL-HKXB201501019.htm

    Wu Y C, He Y Y, He W, et al. Progress in airframe-propulsion integration technology of air-breathing hypersonic vehicle[J]. Acta Aeronautica et Astronautica Sinica, 2015, 36(1): 245-260(in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-HKXB201501019.htm
    [48] Engelund W C, Holland S D, Cockrell C E Jr, et al. Aerodynamic database development for the hyper-X airframe integrated scramjet propulsion experiments[J]. Journal of Spacecraft and Rockets, 2001, 38(6): 803-810. doi: 10.2514/2.3768
  • 加载中
图(14) / 表(4)
计量
  • 文章访问数:  327
  • HTML全文浏览量:  71
  • PDF下载量:  64
  • 被引次数: 0
出版历程
  • 收稿日期:  2021-03-18
  • 修回日期:  2021-03-25
  • 刊出日期:  2022-03-20

目录

    /

    返回文章
    返回