Study Of 2D Temperature Field Reconstruction Based On Ultrasound Inspection

The final object of measurement and reconstruction of temperature field is to realize the visualization of temperature field, and then to monitor and control the temperature state. There are two types of the temperature field measurement, which are contact type and non-contact type. Since the contact type must directly contact with the measured medium, which leads to its application is limited in high temperature, corrosion and other complex environment. The measurement technology of temperature field by acoustic method is a kind of non-contact type, which estimates temperature distribution based on the sound travel time of acoustic wave propagation path. As a new technology with non-contact, non-interference and wide measuring range, it has many advantages like high precision, real-time measurement, convenient maintenance and so on. At present, a huge of researches and applications have been done in many fields, such as the atmospheric surface layer, the stored grain, the industrial boiler flame and the ocean hydrothermal vents.This paper firstly introduces the present research and application of the temperature measurement technology, the detection technology’s research status based on acoustic method both at home and abroad, the acoustic measurement principle, several typical temperature field reconstruction algorithms, and the evaluation standard and influential factors of the reconstruction quality. Secondly, in view of the most common problem existing in many acoustic temperature field reconstruction algorithm: the partition pixel number of the measured area is less than the effective acoustic wave propagation path number, which means the fewer original data, the lower spatial resolution of the temperature field reconstruction. In order to solve the problem, this paper puts forward a kind of temperature field reconstruction algorithm of Gauss radial basis function. The algorithm can be applied to the situation, which the measured region partition pixel number is more than the effective acoustic propagation path number, and it’s also suitable for the reconstruction of complex temperature field. Establishing 8,12,16 ultrasonic transducers system respectively, and then four kinds of typical 2D temperature field models, namely one-peak symmetrical/asymmetrical and two-peak symmetrical/asymmetrical temperature distribution, having been reconstructed under different Gaussian noise interference in the simulation experiments. The reconstruction results and error analysis show that the algorithm owns high accuracy and anti-interference ability. At the same time, this paper also studies on the factors affecting the accuracy of reconstruction based on the new algorithm, and summarizes the influence law of the factors such as the number of acoustic transceiver, acoustic transceiver location layout, the quantity of effective acoustic propagation path, the way of sub region division, the shape parameter value of radial basis function and so on.