LDCT法气液两相流传递特性研究

用极限扩散电流技术（LDCT）对竖直管内的液体单相流与气液两相流的传质特性进行了测量，经三传类比由测量结果获得了传热特性．实验在一内径为18mm的垂直有机玻璃管内进行，实验液体为K3Fe（CN）6-K4Fe（CN）6-NaOH溶液，气体为空气．实验结果与Dittus-Boelter式的计算值及两相流传热的文献值吻合较好．实验中对气液两相流瞬时极限电流信号进行了测量与分析，采用小波分析法对瞬时极限电流波动信号进行了6尺度分解与重构，深入认识了气液两相流的传递过程．对上升管中气弹运动对传热传质的影响提出了假设.

Application of limiting diffusion current technique to investigation of transfer characteristics in two-phase flow

The characteristics of mass and heat transfer of single liquid phase and gas-liquid two-phase flow in a vertical tube were studied with limiting diffusion current technique(LDCT) and the theory of heat and mass transfer analogue.Experiments were carried out in a vertical plexiglass tube of inner diameter of 18 mm. The working liquid was an aqueous solution of K_3Fe(CN)_6-K_4Fe(CN)_6-NaOH.Air was the working gas.The measurements on heat transfer coefficients with LDCT agree well with Dittus-Boelter correlation and references on gas-liquid two-phase heat transfer.The signal fluctuation of limiting diffusion current in gas-liquid two-phase flow was analyzed by wavelet theory with 6-level analysis and reconfiguration to investigate the instantaneous and local characteristics of the process.The influence of Taylor bubble movement on heat mass transfer was assumed based on the above analyses.