A method for measuring the temperature of loose coal body based on the velocity of sound waves

Abstract

The invention discloses a method for testing temperature of loose coal based on acoustic wave velocity. The method comprises the following steps: 1, establishing a testing platform for testing temperature of loose coal; 2, introducing a sound velocity conversion factor of the loose coal; 3, determining the sound velocity conversion factor of the loose coal; 4, acquiring actual temperature of the loose coal. In the method provided by the invention, by establishing the testing platform for testing temperature of loose coal, and giving overall consideration to influence of multiple factors, suchas temperature, acoustic wave frequency, granularity and void fraction, on the acoustic wave velocity, influence of single factor on the acoustic wave velocity can be tested, the sound velocity conversion factor of the loose coal can be determined, a temperature calculation method can be obtained through backward reasoning, and consequently, a loose coal acoustic wave temperature testing mechanismcan be disclosed.

Description

technical field [0001] The invention belongs to the technical field of temperature testing of loose coal bodies, and in particular relates to a method for testing the temperature of loose coal bodies based on sound wave velocity. Background technique [0002] The propagability of sound waves in any continuous medium and the functional relationship between sound velocity and medium temperature are the theoretical basis of sound wave velocity temperature measurement technology. Although the acoustic temperature measurement technology has been applied in many fields, the coal body is a typical porous heterogeneous medium with rich pore structure. The accumulation of loose coal body leads to the accumulation of gas between the coal particles, and the air porosity and particle size of the coal body have a significant impact on the The influence rules of sound propagation path, propagation rate and attenuation degree are complex; because the sound wave is transmitted in the loose ...

AI Technical Summary

Problems solved by technology

Although the acoustic temperature measurement technology has been applied in many fields, the coal body is a typical porous heterogeneous medium with rich pore structure. The accumulation of loose coal body leads to the accumulation of gas between the coal particles, and the air porosity and particle size of the coal body have a significant impact on the The influence rules of sound propagation path, propagation rate and attenuation degree are complex; because the sound wave is transmitted in the loose coal composite medium, the attenuation degree varies greatly with frequency and spatial characteristics, resulting in a very complicated sound wave propagation law in the loose coal body. Propagation in loose coal has the characteristics of continuous transformation of gas-solid two-phase propagation medium. The existing methods and models of acoustic wave temperature measurement in porous media cannot reveal the correlation mechanism between sound waves and temperature in loose coal, which restricts loose coal such as goafs. Application of Acoustic Measurement Method of Temperature Field in Body Environment

Images