外加扰动下垂直管内气-液两相流空隙波特性

采用双环电导探针技术实验研究了外加扰动对垂直上升管内气-液两相流空隙波特征的影响。研究结果表明，气-液两相流空隙波对外加周期性扰动具有频率选择性。在泡状流区，低频扰动能诱发与扰动等频的空隙波；在泡状流／弹状流转变区，低频扰动能加速气泡合并，促进泡状流向弹状流转变；而在弹状流区空隙波特征对外界扰动并不敏感。空隙波的传播速度受外界扰动频率的影响，随着扰动频率的增大，空隙波波速先减少又增大。本文的实验研究发现，存在对气-液两相流空隙波特征影响最为显著的临界扰动频率，在本实验条件和参数范围内，该临界扰动频率为20Hz。

Characteristics of Void Wave in Vertical Gas-Liquid Two-Phase Flows with External Disturbance

Experimental investigation was carried out to study the characteristics of void wave for up-wards gas-liquid flow under external disturbances using double-ring conductance probes. The results show that the void wave exhibits the frequency selectivity to the periodical disturbances exerted. In the bubbly flow regime, low frequency external disturbances can induce void wave, whose frequency is almost equal to that of external disturbances. In the bubble-to-slug transition regime, low frequency external disturbances accelerate bubble coalescence and lead to bubble-to-slug transition. In the slug regime, however, external disturbances have little effect on the characteristics of void wave. Void wave velocity decreases first and then increases with the increasing of disturbance frequency. A critical disturbance frequency was found in the present experimental investigation. The effect of external disturbances on the void wave is most significant under the critical disturbance frequency. The critical frequency obtained in current experimental study was about 20 Hz.