进口压力扰动对氢气燃料旋转爆轰特性的影响

吴宇; 陈煌威; 张顺利; 琚挺; 朱跃进

doi:10.11883/bzycj-2025-0212

进口压力扰动对氢气燃料旋转爆轰特性的影响

doi: 10.11883/bzycj-2025-0212

吴宇^1,,
陈煌威^{1, 2},
张顺利¹,
琚挺¹,
朱跃进^1, ,

1.
江苏大学能源与动力工程学院，江苏镇江 212013
2.
西北工业大学动力与能源学院，陕西西安 710072

基金项目: 国家自然科学基金（12272152）。

详细信息

作者简介:
吴　宇（2000－　），男，硕士生，w1813848978@163.com

通讯作者:
朱跃进（1986－　），男，博士，教授，zyjwind@163.com

中图分类号: V231; O381
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- 被引次数: 0
出版历程
- 收稿日期: 2025-07-10
- 修回日期: 2026-03-14
- 网络出版日期: 2026-03-19

Numerical Investigation of Inlet Pressure Perturbations Effects on Hydrogen-Fueled Rotating Detonation Characteristics

WU Yu^1
,,
CHEN Huangwei^{1, 2},
ZHANG Shunli¹,
JU Ting¹,
ZHU Yuejin^{1
, ,}

1.
School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China
2.
School of Power and Energy, Northwestern Polytechnical University, Xi’an, 710072, China

摘要

摘要: 为研究进口压力扰动对旋转爆轰波（Rotating Detonation Wave，RDW）传播特性的影响，本文基于OpenFOAM平台，采用二维欧拉方程，在进口处施加高频小幅（5 kHz/0.1 MPa）压力扰动，对不同当量比（equivalence ratio，ER）条件下的旋转爆轰特性进行了数值研究。结果表明，不同当量比下的RDW波数及传播模态对进口压力扰动具有显著响应，其变化主要受双波对撞过程及爆轰波前反应物填充特性的共同影响。燃烧室通过自适应调整平衡了能量释放和RDW稳定传播，使系统最终稳定在不同波数的非线性动态平衡状态。在压力扰动作用下，燃烧室内RDW各项特征和参数随扰动频率发生周期性响应，其中RDW结构对扰动更为敏感。当量比及RDW传播模态则共同决定了燃烧释热水平及出口推力，其中比冲主要受当量比控制，与RDW波数变化的相关性较弱。总体而言，高频小幅进口压力扰动主要影响旋转爆轰波的波动结构和传播模态，而对整体性能参数平均特性的影响有限。
- 当量比 /
- 旋转爆轰波 /
- 高频小幅扰动 /
- 热释放速率 /
- 双波对撞
Abstract: To investigate the effects of inlet pressure perturbations on the propagation characteristics of rotating detonation waves (RDWs), numerical simulations were conducted using the OpenFOAM platform and the two-dimensional Euler equations coupled with detailed chemical kinetics. A two-dimensional unfolded rotating detonation combustor model was established to represent the annular chamber. Periodic boundary conditions were applied in the circumferential direction, and non-reflecting boundary conditions were imposed at the outlet. Discretized premixed injection units were specified at the inlet to simulate the reactant supply process. High-frequency, small-amplitude pressure perturbations with a frequency of 5 kHz and an amplitude of 0.1 MPa were superimposed on the inlet total pressure with a mean value of 1 MPa, while the inlet total temperature was fixed at 300 K. Hydrogen–air mixtures with equivalence ratios ranging from 0.6 to 1.6 were considered to examine the influence of reactant composition on RDW behavior under perturbed inlet conditions. The governing equations were solved using a density-based compressible reacting-flow solver with a finite-volume discretization scheme. Convective fluxes were calculated using the KNP central-upwind scheme with a van Leer limiter, and time integration was performed using a second-order Crank–Nicolson method. A detailed hydrogen–air chemical reaction mechanism consisting of 27 elementary reactions was employed to capture detonation dynamics. The results indicate that the RDW wavenumber and propagation mode exhibit significant responses to inlet pressure perturbations at different equivalence ratios, which are mainly governed by the dual-wave collision process and the reactant replenishment characteristics ahead of the detonation front. The combustor adaptively balances the energy release and stable RDW propagation, allowing the system to stabilize at different wavenumbers through a nonlinear dynamic equilibrium. Under inlet pressure perturbations, flow parameters and RDW characteristics exhibit periodic responses at the perturbation frequency, with the RDW structure being more sensitive to the perturbations. The equivalence ratio and RDW propagation mode jointly determine the combustion heat release level and the outlet thrust, whereas the specific impulse is primarily controlled by the equivalence ratio and shows a weak correlation with the RDW wavenumber. High-frequency, small-amplitude inlet pressure perturbations mainly affect the wave structure and propagation mode of RDWs, while the mean performance parameters are only weakly influenced.
- Equivalence ratio /
- Rotating detonation wave /
- High frequency small-amplitude disturbance /
- Heat release rate /
- Double-wave collision

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图 1 二维RDC示意图

Figure 1. Schematic diagram of two-dimensional RDC

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图 2 不同网格尺寸下的温度云图

Figure 2. Temperature contours under different grid sizes

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图 3 RDC内y=7 mm处的压力分布

Figure 3. Pressure distribution at y=7 mm in RDC

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图 4 3 000 μs时的温度与压力云图

Figure 4. Temperature and pressure contours at 3 000 μs

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图 5 Case 2中不同时刻的压力梯度与温度云图

Figure 5. Pressure gradient and temperature contours at different times in Case 2

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图 6 Case 2中RDW高度的演变

Figure 6. Evolution of the RDW height in Case 2

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图 7 Case 6中不同时刻的压力梯度与温度云图

Figure 7. Pressure gradient and temperature contours at different times in Case 6

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图 8 Case 3中不同时刻的压力梯度与温度云图

Figure 8. Pressure gradient and temperature contours at different times in Case 3

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图 9 Case 3中RDW高度的演变

Figure 9. Evolution of the RDW height in Case 3

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图 10 Case 4中不同时刻的压力梯度与温度云图

Figure 10. Pressure gradient and temperature contours at different times in Case 4

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图 11 Case 5中不同时刻的压力梯度与温度云图

Figure 11. Pressure gradient and temperature contours at different times in Case 5

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图 12 监测点压力信号的演化以及RDW传播频率的变化

Figure 12. The evolution of pressure signals at monitoring point and the change of RDW propagation frequency

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图 13 不同当量比下压力信号的FFT结果

Figure 13. FFT results of pressure signals under different equivalence ratios

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图 14 不同当量比下平均热释放速率随时间变化曲线

Figure 14. Variation of mean heat release rate with time for different equivalence ratios

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图 15 Case 1～Case 6平均热释放速率均值的变化曲线

Figure 15. Variation of the mean heat release rate for Case 1-Case 6

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图 16 不同当量比下推力随时间变化曲线

Figure 16. Variation of thrust with time for different equivalence ratios

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图 17 Case1～Case 6推力均值的变化曲线

Figure 17. Variation of mean thrust for Case 1-Case 6

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图 18 不同当量比下比冲随时间变化曲线

Figure 18. Variation of specific impulse with time for different equivalence ratios

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图 19 Case 1～Case 6比冲均值的变化曲线

Figure 19. Variation of mean specific impulse for Case 1-Case 6

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表 1 计算算例设置

Table 1. Computational case settings

Case	A/MPa	f/kHz	ER
1	0.1	5	0.6
2	0.1	5	0.8
3	0.1	5	1.0
4	0.1	5	1.2
5	0.1	5	1.4
6	0.1	5	1.6

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表 2 不同网格尺寸下的RDW速度及峰值压力

Table 2. Velocity and peak pressure of RDW under different grid sizes

网格尺寸/mm	RDW速度/(m·s⁻¹)	RDW峰值压力/MPa
0.1	1 697	6.14
0.2	1 690	5.96
0.4	1 679	5.31

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表 3 所有算例的RDW传播特性

Table 3. RDW propagation characteristics of all cases

Case	ER	$ \overline{f} $/kHz	V_cal/(m·s⁻¹)	V_CJ/(m·s⁻¹)	V_Def/%
1	0.6	8.08	1 615.97	1 718.72	5.97
2	0.8	17.32	1 731.98	1 871.33	7.45
3	1.0	27.49	1 832.42	1 981.29	7.51
4	1.2	28.37	1 891.48	2 036.59	7.13
5	1.4	28.24	1 882.47	2 063.52	8.77
6	1.6	19.79	1 978.94	2 100.21	5.77

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