Page 145 - 《爆炸与冲击》2026年第9期

第 46 卷 齐 治，等： 品字形三喷管火箭橇射流-地效耦合机理及其布局效应 第 9 期

pressure-time curve derived from interior ballistic theory was applied to the nozzle inlet via a user-defined function (UDF). The
sled velocity-time curve, determined from the exterior ballistic particle trajectory equation, was assigned as the far-field
pressure boundary condition, enabling a coupled simulation framework of interior ballistics, exterior ballistics and flow field.
The computational domain utilized a structured grid with refinement in the jet interaction region and near the ground to ensure
calculation accuracy. The velocity and pressure fields obtained from numerical simulations were compared and validated
against jet morphology, impingement height, and vortex core positions recorded by high-speed photography (2 000 Hz). The
flow field structure, pressure distribution, and thermal erosion behavior on the ground under different configurations are
systematically revealed. The results indicate that the small-spacing nozzle arrangement triggers intense jet interference without
ground effect participation, leading to a multi-peak and slow-recovery pressure evolution feature and substantially delays the
flow field relaxation process. The coupling relationship between ground effect and jet interference is dominated by
impingement height. At low impingement height conditions, the jet impinging on the ground induces intense reorganization
and fragmentation of vortex structures, generating wall jets with velocities up to 960 m/s. Consequently, the peak ground
surface temperatures reaches 1 286.6 K with sustained high temperatures, which significantly elevates the risk of rail ablation.
Conversely, a high impingement height effectively suppresses the ground effect, resulting in a more homogeneous and stable
flow field structure. In this case, the peak ground temperature reduced by approximately 65% and maximum velocity reduced
by 58%, significantly mitigating ablation risk. The initial phase (0－8 m) of the rocket sled is identified as the critical region
2
subjected to the most severe thermomechanical loads. During this stage, the average acceleration reaches 832.7 m/s , and the
specific action time per unit distance is prolonged to 1.84 ms/m. Coupled with the transient complex flow field, this constitutes
an extremely high risk for rail ablation. The numerical simulation results show excellent agreement with high-speed
photographic experimental data regarding flow field morphology, impingement height, and vortex core positions, thereby
validating the reliability of the established coupled model. This study elucidates the complex flow mechanisms of multi-nozzle
parallel systems under strongly constrained conditions, and provids important theoretical foundations and design parameters for
structural layout optimization and thermal protection design in high-acceleration, heavy-load rocket sled test systems.
Keywords: rocket sled test; rocket motor; 3D numerical simulation; nozzle flow field; ground effect of flow field

火箭橇系统是地面高超音速动态试验的核心工具 ，通常采用单台或多台固体火箭发动机提供动
[1]
力。在运行过程中，该系统紧贴地面高速运动，其流场环境同时受到自由来流和地面反射气流的影响，
复杂性高。在这样的复杂流场环境下，确保火箭橇稳定运行即抑制振荡和避免削轨至关重要。对于追求
大载荷、高加速度的试验目标，往往需要采用多台发动机并联的方式以大幅提升推力和燃气生成速率。
对火箭橇用火箭发动机尾流场特性及地面效应影响的研究，学者们主要以试验特性研究及数值模
拟这 2 种形式为主 [2-6] 。余元元等 [7] 针对超声速火箭橇开展了数值模拟，分析了不同环境条件下的激波
[8]
特征。周柏航等 对火箭橇动力系统尾流场的影响进行了理论和试验研究，获得了地面效应对双尾喷管
流场分布的影响以及双尾喷管流场之间的相互作用。张俊等 [9] 对火箭发动机燃气射流流场进行了研究，
得到了高速射流流场的分布规律。赵鹏刚等 [10] 以火箭橇气动特性计算精度为出发点，结合风洞试验方
法，分析了地面效应对高速工作的火箭橇流场流动规律的影响。Wang 等 [11] 研究了火箭橇在超声速流动
条件下的激波/轨道耦合作用。王明清 [12] 对多喷管火箭橇系统流场中各喷管尾流场之间的相互作用影
响进行了详细研究。然而，既有研究多聚焦于单发或对称双发布局，其模型与结论难以直接推广至本研
究涉及的大载荷、高加速度、短行程工况下的三发动机品字形非对称布局。针对该布局所特有的多射流
干涉、非对称涡系演化及其与地面效应的非线性耦合机制，现有研究仍较缺乏。
为系统揭示上述机理，本研究针对大载荷、高加速火箭橇试验的特定需求，设计一套呈品字形布局
的 3 台固体火箭发动机并联动力系统，该设计不仅考虑火箭橇系统的动力需求，更充分考虑尾流场环境
和强大的尾部射流对地面轨道及其他测试元件可能造成的冲刷和烧蚀问题。相较于单台火箭发动机和
双发动机，这种品字形并联配置本身在结构上就具有上、下不对称性，这显著加剧了对地面环境的影响，

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