Method for pressure detection of pressure container and based on reflected P-waves and measuring system

Abstract

The invention discloses a method for pressure detection of a pressure container and based on reflected P-waves and a measuring system. The measuring system comprises the cylindrical pressure container, a manual booster pump, a thermostat, an ultrasonic excitation and receiving device, a high-speed oscilloscope and a computer. The fundamental principle of the method for pressure detection is characterized in that based on the ultrasonic sound elastic principle and the theory of plates and shells, after deduction and simplification, a pressure measuring model based on the reflected P-waves is established, and in other words, the relation between the internal pressure of the pressure container and ultrasonic propagation time delay is acquired; then accurate propagation time delay is acquired based on an FIR digital filter and a cross-correlation algorithm; finally in order to reduce temperature interference, a measuring model with the temperature compensating function is provided, and pressure measuring errors are controlled within a small range. The measuring result shows that compared with other similar measuring methods, flexibility and accuracy are higher, and interference resistance is stronger.

Description

technical field [0001] This patent 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 reflected longitudinal waves. Background technique [0002] A pressure vessel is a closed container that bears a pressure load. Its main function is to store and transport high-pressure gas or liquid, or to provide a closed space for heat exchange and material reaction. It is widely used in petrochemical, pharmaceutical, metallurgy, aviation, etc. Aerospace, light industry and textile industries. [0003] Because pressure vessels often work in high-temperature and high-pressure environments, and the media they carry are mostly flammable, highly toxic or corrosive media, pressure vessels are special equipment with high risks. Once leakage, explosion and other accidents occur, it will cause casualties and heavy property losses. Through the analysis of the causes ...

AI Technical Summary

Problems solved by technology

1) Strain method: the output signal is weak, and the anti-interference ability is poor; there is plastic deformation, and it has a large nonlinearity in the state of large strain; the accuracy is low in humid and corrosive atmosphere, and it needs to be replaced frequently; there is zero drift, low measurement accuracy

2) Capacitance method: the dielectric constant is greatly affected by the medium composition and temperature; as the distance between the plates increases, the capacitance value drops sharply, and the change in capacitance value due to pressure changes is very weak, which is only suitable for small tubes diameter measurement; capacitive sensors are easily affected by the surrounding electromagnetic environment, and the measurement accuracy is not high

3) Ultrasonic method: The method based on the change of wave velocity requires ultrasonic waves to pass through the medium in the container, so the measurement results are related to the type of medium, the flow characteristics of the medium, and the temperature of the medium; in addition, the attenuation of ultrasonic waves is serious after passing through the medium, so it is not suitable for large-scale applications. Object

Various factors have caused the above methods to fail to meet the accuracy and sensitivity required for measurement, and it is difficult to meet actual requirements

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