Non-intrusive pressure detection method and measurement system based on time delay intervals of adjacent longitudinal waves

Abstract

The invention discloses a non-intrusive pressure detection method and measurement system based on time delay intervals of adjacent longitudinal waves. According to the invention, the time delay intervals (including those between critical reflection longitudinal waves and first reflection longitudinal waves and those between adjacent reflection longitudinal waves) between adjacent longitudinal waves are selected as measurement parameters; a pressure measurement model of relation between pressure in a container and the time delay intervals between the adjacent longitudinal waves is established by utilizing ultrasonic wave acoustic elastic effect; and estimation of container pressure can be realized through measurement of the time delay intervals. Transit time of a critical refraction longitudinal wave and transit time of the reflection longitudinal waves generated under one excitation pulse are measured at the same time by adopting programmable shielding window technology and a TDC and the time delay intervals of the adjacent longitudinal waves can be obtained through calculation. The method provided by the invention can eliminate influence due to inconsistency of ultrasonic wave probe oscillation starting time and inconsistency of fixed characteristics of a coupling agent, an ultrasonic wave excitation and receiving circuit and a probe and pressure measurement precision can be improved.

Description

technical field [0001] The invention belongs to the technical field of non-intervention pressure detection, and in particular relates to a pressure detection method and measurement system of a pressure vessel based on the time delay interval between adjacent longitudinal waves. Background technique [0002] Pressure equipment is widely used, it involves many fields of industrial production, and is closely connected with people's life. With a broad application background and a huge quantity, such equipment often carries flammable, explosive, highly toxic or corrosive media. Therefore, once an accident occurs, it will often cause serious safety and economic losses. Regular inspection and maintenance of such equipment is one of the effective measures to reduce accidents, and pressure detection is one of the important and effective technologies. [0003] According to whether the measuring device is in contact with the medium in the container, pressure detection is mainly divide...

AI Technical Summary

Problems solved by technology

For the above-mentioned intrusive pressure detection methods, it is often necessary to open holes on the container, so there will be the following disadvantages: 1) Stress concentration is easy to occur at the opening, and the peak value of the stress can reach 3 to 6 times the stress of the film, reducing the service life of the container

2) It is not convenient to add additional test points

3) Most pressure vessels do not allow openings

However, the temperature, the properties of the ultrasonic probe, the installation of the probe, the ultrasonic excitation and receiving circuits, and the coupling agent all have a great influence on the transit time. How to reduce or eliminate the influence of these factors has become an urgent problem to be solved.

Although the two-wave reference measurement method can reduce the influence of temperature, it cannot completely eliminate it, and requires multiple ultrasonic probes, and the measurement device is complicated

The modeling method based on multi-wave fusion synthesizes the information of each waveform and improves the measurement accuracy to a large extent. Over time will have a greater impact

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