Flow and combustion characteristics of dual-mode scramjet under different flight conditions
-
摘要: 为研究煤油燃料矩形截面双模态超燃冲压发动机在不同飞行工况下的流动及燃烧特征，在通过直连式试验验证计算方法的准确性后，对6个不同马赫数及当量比工况进行了三维定常数值模拟，得出了发动机壁面压力、一维质量平均马赫数沿流向的分布规律，分析了各工况下流场中波系结构、释热变化率等特征。研究结果表明：不同工况下发动机明显工作于两类不同的燃烧模态。当发动机处于预燃激波串前传至注油位以前的亚燃模态时，凹槽段波系相对较弱；随着激波串的前移，隔离段中形成明显的分离旋涡结构将燃料卷至上游，部分燃烧在注油位之前已完成；在燃烧室内，分离主要发生于凹槽内部，燃烧释热集中于第一凹槽头部。当发动机处于激波串未前传的超燃模态时，凹槽段波系相对更强，流动参数波动更大，燃烧在注油位以后进行，燃烧室内分离旋涡在流向跨度大，形成从第一凹槽前缘至第二凹槽处的连续流动分离；分离旋涡有助于燃烧向下游传播，因此释热沿流向分布更均匀、更分散。在过渡段诱导流动分离，促使燃烧室内形成大流向跨度的分离旋涡可能有助于燃烧向下游传播，实现分布式释热，避免释热过于集中导致激波串前传。Abstract: In order to study the flow and combustion characteristics of kerosene fueled rectangular dual-mode scramjet under different flight conditions, the accuracy of the numerical method was verified by direct connect experiment. Three-dimensional steady numerical simulations were carried out for six cases with different equivalence ratio and Mach numbers. The distribution of the wall pressure and the one-dimensional mass average Mach number along the flow direction of the scramjet were given. The characteristics of the shock structure and heat release rate were analyzed. The results show that the scramjet works in two different combustion modes under different flight conditions. When the scramjet is in the ramjet-mode operation, the pre combustion shock trains propagate to the front of the fuel injector, and the shock system in the combustor is relatively weak; as the shock train moves forward, the separation vortex structure is formed in the isolator, and the fuel is rolled up to the upstream. Part of the combustion is completed before the injector. The separation of the combustor mainly occurs inside the cavities, and the heat release is concentrated in the head of the first cavity. When the scramjet is in the scramjet-mode operation without shock train forward propagation, the shock system in the cavity section is relatively stronger and the fluctuation of flow parameters is more severe. The combustion occurs downstream of the injector, and the separation vortex in the combustor has a long flow span, forming a continuous flow separation from the leading edge of the first cavity to the second cavity. The separation vortex helps the combustion to propagate downstream, so the heat release is more evenly distributed along the flow direction of the combustor. The flow separation induced in the section between two cavities promotes the formation of the separation vortex with large flow direction span in the combustor, which may help the combustion to propagate downstream, so as to realize distributed heat release and avoid shock train propagation caused by concentrated heat release.
-
Key words:
- dual-mode scramjet /
- heat release rate /
- separation vortex
-
图 4 试验与计算所得壁面压力对比
Figure 4. Comparison between calculation and experiment of wall pressure
图 6 不同工况下一维质量平均马赫数沿程分布
Figure 6. One-dimensional mass average Mach number for different cases
图 7 不同工况的对称面马赫数云图
Figure 7. Centerline planes of Mach number and the shock system for different cases
图 8 不同工况下流道的静温分布
Figure 8. Distributions of temperature in the flowpath for different cases
图 11 不同工况下释热量沿程分布
Figure 11. The heat release distributions along the flow direction for different cases
图 12 不同状态下释热变化率沿程分布
Figure 12. The heat release rate distributions along the flow direction for different cases
图 13 不同工况下发动机表面油流及静压分布
Figure 13. Surface oil flows overlaid with static pressure for different cases
表 1 计算状态及来流参数
Table 1. Research Cases and inflow conditions
工况 飞行马赫数 当量比 隔离段入口参数 马赫数 静压/kPa 静温/K Case 1 5.5 1.0 2.57 72.92 680.14 Case 2 5.6 0.9 2.61 72.21 688.28 Case 3 5.7 0.8 2.67 71.24 694.88 Case 4 5.8 0.7 2.73 69.91 699.11 Case 5 5.9 0.6 2.77 69.23 708.58 Case 6 6.0 0.5 2.87 68.01 702.35 
下载: 导出CSV
-
[1] 邓帆,尘军,谢峰,等. 基于超燃冲压发动机的HIFiRE项目飞行试验研究进展[J]. 航空动力学报,2018,33(3):683-695. doi: 10.13224/j.cnki.jasp.2018.03.022DENG F,CHEN J,XIE F,et al. Research progress on flight tests of HIFiRE project based on scramjet[J]. Journal of Aerospace Power,2018,33(3):683-695. doi: 10.13224/j.cnki.jasp.2018.03.022 [2] FOTIA M L. Mechanics of combustion mode transition in a direct-connect ramjet-scramjet experiment[J]. Journal of Propulsion and Power,2014,31(1):69-78. doi: 10.2514/1.B35171 [3] 浮强,宋文艳,石德永,等. 来流总温对双模态燃烧室模态转换边界的影响[J]. 航空动力学报,2019,34(5):1119-1126. doi: 10.13224/j.cnki.jasp.2019.05.018FU Q,SONG W Y,SHI D Y,et al. Effects of incoming flow total temperature on mode transition boundary in dual mode scramjet combustor[J]. Journal of Aerospace Power,2019,34(5):1119-1126. doi: 10.13224/j.cnki.jasp.2019.05.018 [4] XIAO B G,XING J W,TIAN Y,et al. Experimental and numerical investigations of combustion mode transition in a direct-connect scramjet combustor[J]. Aerospace Science and Technology,2015,46:331-338. doi: 10.1016/j.ast.2015.08.001 [5] XIAO B G,HE C,XING J W,et al. Experimental and numerical investigations of freejet and direct-connect dual-mode scramjet[J]. Aerospace Science and Technology,2018,75:297-303. doi: 10.1016/j.ast.2018.02.004 [6] GOODWIN G B, JOHNSON R F, KESSLER D, et al. Premixed ethylene-air combustion in a dual-mode scramjet cavity combustor with a turbulent inflow[C]//Proc of the AIAA Propulsion and Energy 2019 Forum. 2019. doi: 10.2514/6.2019-4270 [7] 晏至辉,肖保国,何粲,等. 煤油燃料超燃发动机燃烧室温度测量与计算分析[J]. 航空动力学报,2019,34(3):521-528. doi: 10.13224/j.cnki.jasp.2019.03.002YAN Z H,XIAO B G,HE C,et al. Temperature measurement and calculation analysis in a kerosene-fueled scramjet combustor[J]. Journal of Aerospace Power,2019,34(3):521-528. doi: 10.13224/j.cnki.jasp.2019.03.002 [8] 连欢,顾洪斌,周芮旭,等. 超燃冲压发动机模态转换及推力突变实验研究[J]. 实验流体力学,2021,35(1):97-108. doi: 10.11729/syltlx20200069LIAN H,GU H B,ZHOU R X,et al. Investigation of mode transition and thrust performance in transient acceleration and deceleration experiments[J]. Journal of Experiments in Fluid Mechanics,2021,35(1):97-108. doi: 10.11729/syltlx20200069 [9] 车庆丰,齐新华,涂晓波,等. 基于10 kHz高频OH-PLIF的标模发动机燃烧室测量试验[J]. 实验流体力学,2021,35(4):112. doi: 10.11729/syltlx20210088CHE Q F,QI X H,TU X B,et al. 10 kHz OH-PLIF imaging measurement of a scramjet combustor[J]. Journal of Experiments in Fluid Mechanics,2021,35(4):112. doi: 10.11729/syltlx20210088 [10] YENTSCH R J,GAITONDE D V. Numerical investigation of dual-mode operation in a rectangular scramjet flowpath[J]. Journal of Propulsion and Power,2014,30(2):474-489. doi: 10.2514/1.B34994 [11] YENTSCH R J,GAITONDE D V. Unsteady three-dimensional mode transition phenomena in a scramjet flowpath[J]. Journal of Propulsion and Power,2014,31(1):104-122. doi: 10.2514/1.B35205 [12] YENTSCH R J, GAITONDE D V. Comparison of mode-transition phenomena in axisymmetric and rectangular scramjet flowpaths[C]//Proc of the 52nd Aerospace Sciences Meeting. AIAA. doi: 10.2514/6.2014-0625 [13] KOUCHI T,MASUYA G,MITANI T,et al. Mechanism and control of combustion-mode transition in a scramjet engine[J]. Journal of Propulsion and Power,2012,28(1):106-112. doi: 10.2514/1.B34172 [14] TIAN Y,XIAO B G,ZHANG S P,et al. Experimental and computational study on combustion performance of a kerosene fueled dual-mode scramjet engine[J]. Aerospace Science and Technology,2015,46:451-458. doi: 10.1016/j.ast.2015.09.002 [15] 林旭阳,金捷,王方,等. 壁温对氢燃料超燃燃烧室流动特性的影响研究[J]. 推进技术,2020,41(5):1097-1102. doi: 10.13675/j.cnki.tjjs.190358LIN X Y,JIN J,WANG F,et al. Effects of wall temperature on flow characteristics of hydrogen fuel scramjet combustor[J]. Journal of Propulsion Technology,2020,41(5):1097-1102. doi: 10.13675/j.cnki.tjjs.190358 [16] 何粲,邢建文,肖保国,等. 矩形截面超燃发动机不同燃烧模态下的流场特征[J]. 实验流体力学,2018,32(4):12-19. doi: 10.11729/syltlx20180022HE C,XING J W,XIAO B G,et al. Investigation on flow field characteristics of a rectangular scramjet in different combustion modes[J]. Journal of Experiments in Fluid Mechanics,2018,32(4):12-19. doi: 10.11729/syltlx20180022 [17] 杨顺华. 碳氢燃料超燃冲压发动机数值研究[D]. 绵阳: 中国空气动力研究与发展中心, 2006.YANG S H. Numerical study of hydrocarbon fuel scramjet engine[D]. Mianyang: China Aerodynamics Research and Development Center, 2006. [18] 何粲,邢建文,肖保国,等. 反压对隔离段激波串结构的影响[J]. 航空动力学报,2016,31(5):1242-1251. doi: 10.13224/j.cnki.jasp.2016.05.028HE C,XING J W,XIAO B G,et al. Influence of back pressure on shock train structure in isolator[J]. Journal of Aerospace Power,2016,31(5):1242-1251. doi: 10.13224/j.cnki.jasp.2016.05.028 [19] 赵慧勇. 超燃冲压整体发动机并行数值研究[D]. 绵阳: 中国空气动力研究与发展中心, 2005.ZHAO H Y. Parallel numerical research on scramjet integral engine[D]. Mianyang: China Aerodynamics Research and Development Center, 2005. [20] HE C, XING J W, XIAO B G, et al. Investigation on Flow field characteristics of an ethylene fueled scramjet in different combustion modes[C]//Proc of the 21st AIAA International Space Planes and Hypersonics Technologies Conference. 2017. doi: 10.2514/6.2017-2303 [21] KOK J C. Resolving the dependence on freestream values for the k-omega turbulence model[J]. AIAA Journal,2000,38:1292-1295. doi: 10.2514/3.14547 [22] LE J L, YANG S H, LIU W X, et al. Massively parallel simulations of kerosene-fueled model scramjet[C]//Proc of the AIAA/CIRA 13th International Space Planes and Hypersonics Systems and Technologies Conference. 2012. doi: 10.2514/6.2005-3318 [23] FAN C J, Modern Flow Visualization[M]. Beijing: National Defence Industry Press, 2002: 22-37. [24] MURRAY T,DAVID J P. Topology of three-dimensional separated flows[J]. Journal of Propulsion and Power,2014,30(2):474-489. -
点击查看大图
图(13) / 表(1)
计量
- 文章访问数: 583
- HTML全文浏览量: 226
- PDF下载量: 82
- 被引次数: 0
