Measurement of the temperature distribution in fluids using ultrasonic tomography

This paper describes the non-invasive measurement of the distributed temperature in liquid using an ultrasound time-of-flight technique. The system uses eight piezoelectric transducers mounted circumferentially inside a pipe of diameter 300 mm. A reconstruction method was used to evaluate the temperature distribution within the plane of the transducers. The method is based on the approximation of the inverse function of the velocity of ultrasonic propagation by the linear combination of discrete and polynomial basis functions. A modified Gauss method is used solve the equations. The reasons for the non-uniform measurement path density is discussed