Assessing mixing uniformity of bubbles in direct-contact boiling heat transfer process

In order to assess the mixing performance of multiphase flow disturbed by bubble swarms in direct-contact boiling heat transfer process, a novel technique based on image processing technique and pixel discrepancy theory was proposed to test and measure the mixing uniformity of complex fluids. The gray scale matrix of bubbles RGB image was used to calculate discrepancy. The mixed state of gas-liquid in direct-contact heat transfer was characterized accurately and quantitatively. The values reflect the distribution status of bubbles swarm. Different mixing uniformity of multiphase flow systems have different mixing time. Pixel discrepancy time series were employed for normality test and chaotic detection. It is found that the data is approximate normal distribution and the whole mixing processes are chaotic. A simple method was used to solve a complicated problem that the quantification and characterization of bubbles behavior under the complicated condition. The alternative route brings new insights to study multiphase flow identification and can act as a guide to enhancing the chaotic behavior of systems.