水平管泡状流强制扰动下的空隙波特性

在水平透明玻璃管内以空气和水为流体介质研究了强制扰动下气-液两相泡状流空隙波的特性,应用高速摄影仪和电导探针,对不同扰动频率下空隙波的不稳定性和波速进行了观察测量.研究结果表明,空隙波对于外界周期性扰动具有频率选择特性,随含气率的提高,扰动传播的衰减减慢,流动不稳定性增加.对应于一定的扰动频率,空隙波有不同的速度概率分布,呈现色散特性.空隙波的波速概率分布在两相混合流速处出现峰值,向两侧加速递减,与高斯分布接近.

Characteristics of Void Fraction Wave in Horizontal Bubbly Flow with Forced Disturbance

Characteristics of void fraction wave were investigated in a horizontal water-gas two-phase bubbly flow. Under different periodical disturbances, the instability and the celerity of void fraction wave were observed and measured with digital high-speed video system and conductivity probe. The results show that the void fraction wave has the frequency selectivity to the periodical disturbance exerted. The attenuation of distrurbance propagation is slowed down and the instability is enhanced with the increasing void fraction. For a given periodical disturbance the void fraction wave has various propagation velocities, behaving as a kind of dispersive wave. The peak of the wave celerity probability distribution appears within the mean velocity region of the two-phase bubbly flow, and the distribution approximately fits in with the Gaussian distribution.