Experimental study on effects of nozzles on gas bubble shapes and pressure characteristics of underwater detonation
-
摘要: 针对具有不同类型喷管的爆轰管在水下爆轰中形成的燃气射流问题，搭建了爆轰实验平台，研究了单次爆轰过程中尾部喷管对水下气泡形态与压力特征的影响。采用数字粒子图像测速技术对高速摄影机拍摄得到的气泡脉动图片进行流场可视化分析，得到各喷管工况下的气泡速度场。为了确认爆轰管内是否形成稳定爆轰波，并观察爆轰波在气液两相界面上的透反射特性，爆轰管尾部安装有2个动态压力传感器，同时在距离喷管一定距离处设置一个水下爆炸传感器，以监测水中传播的压力波。结果表明：扩张喷管工况下的气泡脉动过程与直喷管工况基本一致，但扩张喷管提高了燃气射流速度，气泡膨胀体积更大；因为燃气射流的持续性，收敛喷管工况下的气泡脉动过程具有明显差异，气泡膨胀体积较小，但气泡二次脉动时长相较于一次脉动时长衰减更小；扩张喷管提高了气泡脉动强度，扩张喷管工况下的气泡脉动压力与透射冲击波压力远大于直喷管工况下的气泡脉动压力与透射冲击波压力；收敛喷管工况下的气泡脉动压力与透射冲击波压力都较小，但收敛喷管燃气射流的持续性减缓了气泡脉动压力的衰减速度。相比于直喷管，扩张喷管工况下的气泡脉动时间、气泡脉动压力与透射冲击波压力都更大。收敛喷管工况下的气泡脉动持续时间较短，并且收敛喷管对透射冲击波压力和气泡脉动压力均具有明显的抑制作用。Abstract: A detonation experimental system was established to explore the characteristics of underwater detonation gas jets from the detonation tubes with different types of nozzles. The effects of different types of nozzles on underwater bubble shapes and pressure characteristics during detonation were experimentally studied. The digital particle image velocimetry was used to visualize the bubble pulsation pictures captured by a high-speed camera, and the bubble velocity fields in the different nozzle cases were obtained. Two dynamic pressure sensors were installed at the end of the detonation tube to confirm whether the stable detonation wave was formed, and to observe the transmission and reflection characteristics of the detonation wave on the gas-liquid two-phase interface, respectively. An underwater explosion sensor was installed at a certain distance from the nozzle to measure the underwater pressure wave. The results show that the bubble pulsation process in the divergent nozzle case is basically the same as that in the case of the straight nozzle, but the divergent nozzle improves the gas jet velocity and increases the bubble volume of the first bubble pulsation. The combined effect of the convergent nozzle and its reflected shock wave reduces the injection speed of the detonation gas. Because of the continuity of the gas jet, the bubble pulsation process in the convergent nozzle case is obviously different. The maximum bubble volume in the convergent nozzle case is smaller, but the attenuation of the second bubble pulsation duration is smaller than that of the first pulsation duration. The divergent nozzle increases the gas velocity and kinetic energy, which enhances the bubble pulsation intensity, the bubble pulsation pressure and transmitted shock wave pressure in the divergent nozzle case are much higher than those in the straight nozzle case. The bubble pulsation pressure and the transmitted shock wave pressure in the convergent nozzle case are both low, but the continuity of the convergent nozzle gas jet retards the attenuation speed of the bubble pulsation pressure. Compared with the straight nozzle, the bubble pulsation time in the divergent nozzle case is longer, the bubble pulsation pressure and transmitted shock wave pressure are higher. The duration of the bubble pulsation in the convergent nozzle case is shorter, and the convergent nozzle can obviously inhibit the transmitted shock wave pressure and the bubble pulsation pressure.
-
Key words:
- nozzle /
- underwater detonation /
- bubble pulsation /
- bubble shape /
- underwater pressure
-
1. 加州大学研究人员在螳螂虾指节中发现一种高刚度大阻尼抗冲击涂层
自然界利用现有资源，在有限的环境条件下组建了轻质、坚固、坚韧的材料。例如，螳螂虾指关节的迎撞面就是这类典型的复合材料，此类虾具有在摄食过程中避免高速碰撞造成巨大伤害的能力。美国加州大学研究人员发现螳螂虾的指节包含一层由纳米颗粒紧密堆积的抗冲击涂层，这些纳米颗粒由排列整齐的小纳米晶体组成。在高应变率冲击下（约104 s−1），粒子旋转和平移，而纳米晶网络在低角度晶界处发生断裂，形成位错并发生非晶化。此外，这种材料在保持高刚度（弹性模量约为58.9 GPa）的情况下还具有较大的阻尼（损耗系数约为0.02），相互渗透的有机网状结构提供了额外的增韧和阻尼，这种罕见的刚度和阻尼组合在工程材料中并不常见，其性能也优于许多工程材料。这些新发现可为结构的高速冲击和破坏失效提供新的研究思路。
源自：HUANG W, MEHDI S, NICOLAS G Z, et al. A natural impact-resistant bicontinuous composite nanoparticle coating [J]. Nature Materials, 2020, 19: 1236−1243.
2. 迈阿密大学等研究人员首次定量描述了铜箔材料在高应变率下的失效过程
理解高速碰撞以及随后的高应变率材料变形和潜在的灾难性破坏，对于包括天体物理学、材料科学和航空航天工程在内的系列科学和工程学科至关重要。由于在极短时间尺度下，用实验来量化材料的演变面临着巨大挑战，相关变形和破坏机制还很不明确。美国迈阿密大学等研究人员将铜箔通过皮秒激光烧蚀实现快速变形（0.5×109 s−1），并利用30-fs超快X射线自由电子(XFEL)脉冲进行原位探测，首次定量描述了材料在高应变率条件下的失效过程。结果发现最终破坏是通过空洞成核、增长和聚合发生的，与分子动力学模拟的结果吻合较好。发展和应用具有飞秒分辨率的原位超快小角度X射线散射（SAXS）对高应变率层裂破坏进行定量表征，是对广角X射线散射（WAXS）的补充，具有重要的应用价值。
源自：JAMES C, ANDREW H, DAVID M, et al. Femtosecond quantification of void evolution during rapid material failure [J]. Science Advances, 2020, 6(51): eabb4434.
3. 韩国浦项科技大学等研究人员发现了高熵合金纳米材料在应变率5×10−2 s−1下的超塑性
超塑性描述的是材料以拉伸延伸的形式将大塑性变形维持到其原始长度400%以上的能力，但通常只能在低应变率（约10−4 s−1）下观察到，这使得加工时间大大增加，由于经济原因导致不适合大规模生产。而超过10−2 s−1应变率下的超塑性，通常只能在低强度的镁和铝合金中才能出现。韩国浦项科技大学等研究人员通过高压扭转试验，发现了Al9(CoCrFeMnNi)91高熵合金纳米材料在应变率5×10−2 s−1下的超塑性，其伸长率达到了原始长度的2000%。多相合金中的高压扭转诱导晶粒细化与热塑性变形过程中的有限晶粒增长相结合，通过位错活动调节晶界滑移，实现了高应变率下的超塑性。
源自：NGUYEN N T C, ASGHARI-RAD P, SATHIYAMOORTHI P, et al. Ultrahigh high-strain-rate superplasticity in a nanostructured high-entropy alloy [J]. Nature Communications, 2020, 11: 2736.
4. 佛罗里达大学等研究人员开发了一种用于描述含能材料激波-爆炸转换的多尺度方法
佛罗里达大学、佛罗里达理工学院以及洛斯阿拉莫斯国家实验室等科学家合作开发了一种耦合微观尺度空洞坍塌动力学到介观尺度模拟中的多尺度方法，可以描述微观结构在起爆中发挥的重要作用。第一步，作者进行空隙塌陷模拟，并收集点火时间和总输出功率与冲击压力和空隙直径的关系；第二步，通过将功率沉积项添加到能量方程，将第一步的信息反馈给介观尺度模拟。该研究通过使用单独的反应物和产物状态方程，并在反应区中定义了混合规则，可以获得与实验数据更好的一致性。由于没有HMX单晶数据，因此用PBX9501替代（即含95%HMX），优势是PBX9501数据比较全面。另一个改进是介观尺度上的动力学建模。作者采用了基于压力的幂定律，针对实验的Pop-plot数据和CJ点附近爆轰曲线斜率进行了校准。以前的校准过程是在连续范围内进行的，没有考虑微观结构的细节；该论文是研究空洞塌陷而引起的起爆，因此包括了微观结构的细节。
源自：THOMAS J L, ZHANG J, SHORT M. Multiscale approach to shock to detonation transition in energetic materials [J]. Propellants, Explosives, Pyrotechnics, 2020, 45: 316−329.
5. 中物院化工材料研究所等研究人员制备出具有类石墨烯结构的稠环单质炸药
中物院化工材料研究所与美国爱达荷大学研究人员近期利用分子间氢键和偶极-偶极协同相互作用，联合研究制备出一种新的含能材料NAPTO。该物质不仅含有稠环母体结构，还具有超平的二维层状堆积结构，分子中所有原子处于同一平面内，二面角均为0°或180°。其平面性优于常见的二维层状单质炸药如TATB、FOX-7等，成为首个具有类石墨烯结构的稠环单质炸药，且层间距仅为2.855×10−10 m。该新型化合物能量高（爆速为9.12 km/s，爆压为35.1 GPa）、外部刺激敏感度优异（撞击感度为18 J，摩擦感度为325 N，静电放电感度为0.32 J）、热分解温度高（203.2 ℃），因此具有高能量和低机械感度双重优点。
源自：FENG Y A, DENG M C, SONG S W，et al. Construction of an unusual two-dimensional layered structure for fused-ring energetic materials with high energy and good stability [J]. Engineering, 2020, 6(9): 1006−1012.
（敬霖 编译）
-
图 3 直喷管和扩张喷管水下爆轰燃气射流气泡形态及速度场
Figure 3. Bubble shapes and velocity fields of underwater detonation gas jets from detonation tubes with straight and divergent nozzles, respectively
图 4 收敛喷管水下爆轰燃气射流气泡形态和速度场
Figure 4. Bubble shapes and velocity fields of the underwater detonation gas jet from the detonation tube with a convergent nozzle
图 5 爆轰管尾部监测点压力随时间的变化
Figure 5. Pressure-time curves of monitoring points at the tail of the detonation tube
图 7 不同喷管气泡脉动压力随时间的变化
Figure 7. Bubble pulsation pressure-time curves of different nozzles
图 8 收敛喷管气泡脉动压力随时间的变化
Figure 8. Bubble pulsating pressure-time curve of the convergent nozzle
表 1 直喷管和扩张喷管的气泡脉动压力极值和脉动时间
Table 1. Pressure extrema and bubble pulsation time of straight and divergent nozzles
喷管 pA/kPa pB/kPa pC/kPa t1/ms t2/ms 直喷管 23.50 12.38 2.54 28.70 20.63 扩张喷管 31.41 13.41 7.52 31.60 21.48 
下载: 导出CSV
-
[1] ROSATO D A, THORNTON M, SOSA J, et al. Stabilized detonation for hypersonic propulsion [J]. Proceedings of the National Academy of Sciences of the United States of America, 2021, 118(20): e2102244118. DOI: 10.1073/pnas.2102244118. [2] 潘振华, 范宝春, 归明月, 等. 流动系统中爆轰波传播特性的数值模拟 [J]. 爆炸与冲击, 2010, 30(6): 593–597. DOI: 10.11883/1001-1455(2010)06-0593-05.PAN Z H, FAN B C, GUI M Y, et al. Numerical simulation of detonation wave propagation in a flow system [J]. Explosion and Shock Waves, 2010, 30(6): 593–597. DOI: 10.11883/1001-1455(2010)06-0593-05. [3] 王兵, 谢峤峰, 闻浩诚, 等. 爆震发动机研究进展 [J]. 推进技术, 2021, 42(4): 721–737. DOI: 10.13675/j.cnki.tjjs.210109.WANG B, XIE Q F, WEN H C, et al. Research progress of detonation engines [J]. Journal of Propulsion Technology, 2021, 42(4): 721–737. DOI: 10.13675/j.cnki.tjjs.210109. [4] 张春, 郁伟, 王宝寿. 水下超声速燃气射流的初期流场特性研究 [J]. 兵工学报, 2018, 39(5): 961–968. DOI: 10.3969/j.issn.1000-1093.2018.05.016.ZHANG C, YU W, WANG B S. Research on the initial flow field characteristics of underwater supersonic gas jets [J]. Acta Armamentarii, 2018, 39(5): 961–968. DOI: 10.3969/j.issn.1000-1093.2018.05.016. [5] 王乐勤, 郝宗睿, 吴大转. 水下气体射流初期流场的数值研究 [J]. 工程热物理学报, 2009, 30(7): 1132–1135. DOI: 10.3321/j.issn:0253-231X.2009.07.014.WANG L Q, HAO Z R, WU D Z. Numerical simulation of initial flow field of underwater gas jet [J]. Journal of Engineering Thermophysics, 2009, 30(7): 1132–1135. DOI: 10.3321/j.issn:0253-231X.2009.07.014. [6] 张焕好, 郭则庆, 王瑞琦, 等. 水下超声速气体射流的初始流动特性研究 [J]. 振动与冲击, 2019, 38(6): 88–93; 131. DOI: 10.13465/j.cnki.jvs.2019.06.013.ZHANG H H, GUO Z Q, WANG R Q, et al. Initial flow characteristics of an underwater supersonic gas jet [J]. Journal of Vibration and Shock, 2019, 38(6): 88–93; 131. DOI: 10.13465/j.cnki.jvs.2019.06.013. [7] ZHANG Q B, FAN W, WANG K, et al. Impact of nozzles on a valveless pulse detonation rocket engine without the purge process [J]. Applied Thermal Engineering, 2016, 100: 1161–1168. DOI: 10.1016/j.applthermaleng.2016.02.135. [8] 陈焕龙, 王柠, 刘华坪, 等. 不同发射深度下喷管燃气射流特性研究 [J]. 水动力学研究与进展: A辑, 2012, 27(6): 659–666. DOI: 10.3969/j.issn1000-4874.2012.06.005.CHEN H L, WANG N, LIU H P, et al. Investigation of nozzle gas jet characteristics with different launch depth underwater [J]. Chinese Journal of Hydrodynamics, 2012, 27(6): 659–666. DOI: 10.3969/j.issn1000-4874.2012.06.005. [9] FROLOV S M, AVDEEV K A, AKSENOV V S, et al. Pulsed detonation hydroramjet: simulations and experiments [J]. Shock Waves, 2020, 30(3): 221–234. DOI: 10.1007/s00193-019-00906-2. [10] FROLOV S M, AVDEEV K A, AKSENOV V S, et al. Experimental and computational studies of shock wave-to-bubbly water momentum transfer [J]. International Journal of Multiphase Flow, 2017, 92: 20–38. DOI: 10.1016/j.ijmultiphaseflow.2017.01.016. [11] LIU W, LI N, WENG C S, et al. Bubble dynamics and pressure field characteristics of underwater detonation gas jet generated by a detonation tube [J]. Physics of Fluids, 2021, 33(2): 023302. DOI: 10.1063/5.0029729. [12] LIU W, LI N, HUANG X L, et al. Experimental study of underwater pulse detonation gas jets: bubble velocity field and time-frequency characteristics of pressure field [J]. Physics of Fluids, 2021, 33(8): 083324. DOI: 10.1063/5.0060686. [13] 侯子伟, 翁春生, 贾芳, 等. 水下爆轰燃气泡形态与激波传播过程研究 [J]. 推进技术, 2021, 42(4): 755–764. DOI: 10.13675/j.cnki.tjjs.200390.HOU Z W, WENG C S, JIA F, et al. Gas bubble shape and shock wave propagation process of underwater detonation [J]. Journal of Propulsion Technology, 2021, 42(4): 755–764. DOI: 10.13675/j.cnki.tjjs.200390. [14] HOU Z W, LI N, HUANG X L, et al. Experimental study on pressure evolution of detonation waves penetrating into water [J]. Physics of Fluids, 2022, 34(7): 076110. DOI: 10.1063/5.0100446. [15] 李旭东, 王春, 姜宗林. 喷管对脉冲爆轰发动机性能的影响 [J]. 力学学报, 2011, 43(1): 1–10. DOI: 10.6052/0459-1879-2011-1-lxxb2009-754.LI X D, WANG C, JIANG Z L. Nozzle effects on performance of pulse detonation engines [J]. Chinese Journal of Theoretical and Applied Mechanics, 2011, 43(1): 1–10. DOI: 10.6052/0459-1879-2011-1-lxxb2009-754. [16] YUNGSTER S. Analysis of nozzle and ejector effects on pulse detonation engine performance [C]//Proceedings of the 41st Aerospace Sciences Meeting and Exhibit. Reno, Nevada, USA: AIAA, 2003: 1316. DOI: 10.2514/6.2003-1316. [17] 范玮, 严传俊, 李强, 等. 脉冲爆震发动机尾喷管的实验 [J]. 航空动力学报, 2007, 22(6): 869–872. DOI: 10.3969/j.issn.1000-8055.2007.06.004.FAN W, YAN C J, LI Q, et al. Experimental investigation on pulse detonation engine nozzles [J]. Journal of Aerospace Power, 2007, 22(6): 869–872. DOI: 10.3969/j.issn.1000-8055.2007.06.004. [18] 汤龙生, 刘宇, 吴智锋, 等. 水下超声速燃气射流气泡的生长及压力波传播特性实验研究 [J]. 推进技术, 2011, 32(3): 417–420. DOI: 10.13675/j.cnki.tjjs.2011.03.002.TANG L S, LIU Y, WU Z F, et al. Experimental study on characteristics of bubble growth and pressure wave propagation by supersonic gas jets under water [J]. Journal of Propulsion Technology, 2011, 32(3): 417–420. DOI: 10.13675/j.cnki.tjjs.2011.03.002. [19] LINCK M, GUPTA A, BOURHIS G, et al. Combustion characteristics of pressurized swirling spray flame and unsteady two-phase exhaust jet [C]//Proceedings of the 44th AIAA Aerospace Sciences Meeting and Exhibit. Reno, Nevada, USA: AIAA, 2006: 377. DOI: 10.2514/6.2006-377. [20] 唐嘉宁, 刘向阳, 李世鹏, 等. 水下固体火箭发动机推力特性研究 [J]. 导弹与航天运载技术, 2012(5): 15–21. DOI: 10.3969/j.issn.1006-2793.2012.03.008.TANG J N, LIU X Y, LI S P, et al. Study on the thrust characteristics of the underwater solid rocket motor [J]. Missiles and Space Vehicles, 2012(5): 15–21. DOI: 10.3969/j.issn.1006-2793.2012.03.008. [21] TANG J N, WANG N F, SHYY W. Flow structures of gaseous jets injected into water for underwater propulsion [J]. Acta Mechanica Sinica, 2011, 27(4): 461–472. DOI: 10.1007/s10409-011-0474-4. [22] 王利利, 刘影, 李达钦, 等. 固体火箭发动机水下超音速射流数值研究 [J]. 兵工学报, 2019, 40(6): 1161–1170. DOI: 10.3969/j.issn.1000-1093.2019.06.006.WANG L L, LIU Y, LI D Q, et al. Numerical study of underwater supersonic gas jets for solid rocket engine [J]. Acta Armamentarii, 2019, 40(6): 1161–1170. DOI: 10.3969/j.issn.1000-1093.2019.06.006. [23] 曹嘉怡, 鲁传敬, 李杰, 等. 水下超声速燃气射流动力学特性研究 [J]. 水动力学研究与进展:A辑, 2009, 24(5): 575–582. DOI: 10.16076/j.cnki.cjhd.2009.05.003.CAO J Y, LU C J, LI J, et al. Research on dynamic characteristics of underwater superasonic gas jets [J]. Journal of Hydrodynamics, 2009, 24(5): 575–582. DOI: 10.16076/j.cnki.cjhd.2009.05.003. [24] GONG Z X, LU C J, LI J, et al. The gas jet behavior in submerged Laval nozzle flow [J]. Journal of Hydrodynamics, Ser. B, 2017, 29(6): 1035–1043. DOI: 10.1016/S1001-6058(16)60817-X. [25] BLOCH G, KUCZATY J, SATTELMAYER T. Application of high-speed digital holographic interferometry for the analysis of temperature distributions and velocity fields in subcooled flow boiling [J]. Experiments in Fluids, 2014, 55(2): 1678. DOI: 10.1007/s00348-014-1678-8. [26] GORDON S, MCBRIDE B J. Computer program for calculation of complex chemical equilibrium compositions and applications. Part 1: analysis: NASA 1311 [R]. Washington, USA: National Aeronautics and Space Administration, 1994: 39–40. -
下载:
计量
- 文章访问数: 508
- HTML全文浏览量: 160
- PDF下载量: 91
- 被引次数: 0