声学法炉内温度场与速度场协同测量方法研究

实时监测炉内燃烧温度场和烟气速度场是保证锅炉安全、经济运行的重要手段，声学法测物理场被认为是一种非侵入性和有效的测量方法。本文提出了一种基于声波法的炉内温度场和烟气速度场的协同测量新方法，建立了基于径向基函数的多物理场重建模型，采用Tikhonov正则化算法求解不适定问题，同时考虑了声波的折射效应对物理场的重建影响。采用典型的炉内物理场模型进行了数值模拟，模拟结果表明，本文方法能够很好的协同重建温度场和速度场。当考虑声线弯曲时能够显著提高各物理场的重建质量。算法具有较好的适应性和良好的抗噪性能，重建精度较高，标准均方根误差在10%以下。模拟实验平均计算时间为31.4 s,可保证炉内声学测量的实时性。声学法协同测量多物理场可为优化炉膛燃烧过程提供依据。

Study on simultaneous measurement of temperature and velocity field in furnace based on acoustic tomography

Real time monitoring of combustion temperature field and flue gas velocity field in boiler is important to ensure the operation of boiler safely and economically. The acoustic tomography (AT) is considered to be a non-intrusive and effective method that can give information about temperature distribution and flow field. In this article, a novel method based on AT technology is proposed to reconstruct the temperature and velocity fields simultaneously. A multi-physical field reconstruction model based on radial basis function is formulated, and the Tikhonov regularization algorithm is used to solve ill-posed problems. In addition, we consider the refraction effect of the sound waves in the process of reconstruction. The numerical simulation results show the effectiveness of the proposed measurement method in simultaneously reconstructing the complex temperature distribution and velocity field. When the refraction effect of the sound waves is considered, the method can significantly improve the reconstruction quality of various physical fields. The reconstruction method has good anti-noise performance and high reconstruction accuracy with the normalized root mean square error of less than 10% . The average calculation time of the simulation experiment is 31. 4 s, which can ensure the real-time performance of the acoustic measurement in the furnace. The proposed method of temperature and velocity fields simultaneous measurement can provide information to optimize the thermal fluid and combustion process in furnace.