Method for simultaneously measuring internal temperatures and wall thicknesses of high-temperature structures under steady-state conditions

Abstract

The invention discloses a method for simultaneously measuring internal temperatures and wall thicknesses of high-temperature structures under steady-state conditions. The method has the advantages that the problem of incapability of simultaneously measuring internal temperatures and wall thicknesses of existing high-temperature structures under existing steady-state conditions can be solved by theaid of the method; the method is based on ultrasonic detection signals, and structure thickness and internal temperature simultaneous measurement is transformed into heat boundary conditions of heatconduction problems and multi-parameter identification problems for structure thicknesses; the initial time and time steps are prolonged, transiently solved internal non-uniform temperature field andsteady-state results of the structures keep consistent, a valid measurement datum under steady-state heat transfer conditions is transformed into a plurality of valid measurement data under transientconditions, and accordingly the problem of matrix singularity due to insufficient input information during multi-parameter identification can be effectively solved by the aid of the method; the inverse heat conduction problems can be solved, and accordingly the internal temperatures and the thicknesses of the related structures under the steady-state heat transfer conditions can be quickly and nondestructively measured in a non-contact manner by the aid of the method.

Description

technical field [0001] The invention belongs to the technical field of ultrasonic detection, and in particular relates to a method for simultaneously measuring the internal temperature and wall thickness of a high-temperature structure under steady-state conditions. Background technique [0002] High-temperature thickness measurement based on ultrasonic method, especially high-temperature fixed-point thickness measurement, is one of the most commonly used non-destructive testing methods in safety assessment in petroleum, chemical, machinery and other fields. However, both the temperature and wall thickness of the structure in engineering practice are usually unknown, and the commonly used temperature coefficient compensation method is difficult to accurately describe the gradient change of the non-uniform temperature field inside the measured structure, and the ultrasonic propagation path will be too large or too small When the sound is on, it brings severe challenges to hig...

AI Technical Summary

Problems solved by technology

However, both the temperature and wall thickness of the structure in engineering practice are usually unknown, and the commonly used temperature coefficient compensation method is difficult to accurately describe the gradient change of the non-uniform temperature field inside the measured structure, and the ultrasonic propagation path will be too large or too small Acoustic time on the surface brings severe challenges to high temperature thickness measurement

At the same time, under the condition of long-term operation of most in-service high-temperature equipment, the internal temperature field of the structure is usually stable, which makes it possible to obtain only one effective measurement data in the measurement of ultrasonic acoustic time information

When the measured data is less than the number of parameters to be measured, the accurate value to be predicted cannot be obtained based on the solution of the inverse problem

This further increases the difficulty of high temperature thickness measurement

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