油水两相流过程的可视化检测对多相流研究与石油和化工等工业生产具有重要意义。超声层析成像技术具有非侵入、无辐射、安装方便等优点，在油水两相流检测中有很好的应用前景。针对超声层析成像实现低对比度声学特性的油、水两相介质分布重建问题，提出一种高分辨率图像重建方法。该方法通过构建基于阶段奇异值分解的降维同步代数重建算法，在保证重建精度的同时提高重建速度，并采用高斯回归模型将低分辨率的重建结果转化为高分辨率图像。仿真模拟测试结果表明，该算法重建图像误差小、分辨率较高，能满足实时成像要求。
Visualized measurement of oil-water two-phase flow is of vital importance in multi-phase flow measurement and process industry. Ultrasonic tomography (UT) is widely applied in two-phase flow measurement due to its non-invasive, non-radiative, safe, and portable advantages. Aiming at UT reconstruction of oil-water two-phase medium with low acoustic impedance, we propose a high-resolution reconstruction algorithm based on Gaussian regression prediction. The iteratively simultaneously algebraic reconstruction technique is modified with high pass filter, and the truncated singular value decomposition is used to reduce dimensionality of the coefficient matrix. Gaussian process regression is applied to gain high-resolution image. Simulation results indicate that the proposed algorithm provides high accuracy and high-resolution reconstruction with fast computing speed.
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