Suppression of gas oscillation is essential to realize the stable operation of the cryogenic helium piping systems. In the current study, a structural solution, that is, a tube is connected to the main pipe as an adjustment accessory to control unfavourable gas oscillations. The model with dual temperature gradients is developed by introducing an adjustment tube. The effects of the parameter sensitive to the distribution of the dual temperature gradients on the thermoacoustic oscillation (TAO) characteristics are revealed. The results demonstrate that the asymmetry of the temperature distribution and a large frequency deviation makes it easier to achieve the oscillation-free operation of the system. At the initial start-up stage, the phase relationship between the acoustic waves is shown. As the cold length to warm length ratio decreases, the phase difference between sound waves increases, and the oscillation-free operation is accomplished when the cold length to warm length ratio is 0.11. Therefore, an approach of adjusting the length ratio in the adjustment tube can control thermoacoustic oscillations of cryogenic fluid.

抑制气体振荡对于实现低温氦气管道系统的稳定运行至关重要。在目前的研究中，一种结构解决方案，即在主管上连接一根管子作为调节附件来控制不利的气体振荡。通过引入调节管开发了具有双温度梯度的模型。揭示了对双温度梯度分布敏感的参数对热声振荡 (TAO) 特性的影响。结果表明，温度分布的不对称性和较大的频率偏差使得系统更容易实现无振荡运行。在初始启动阶段，显示了声波之间的相位关系。随着冷长与暖长比的减小，声波相位差增大，冷长暖长比为0.11时实现无振荡运行。因此，调节调节管中的长度比的方法可以控制低温流体的热声振荡。