Method for inverting position of heat source in high-temperature area of underground coal mine goaf

Abstract

The invention discloses a method for inverting the position of a heat source in a high-temperature area of an underground coal mine goaf, and relates to the technical field of goaf temperature monitoring. The method comprises the following steps: firstly, selecting a possible high-temperature space, and measuring temperature values of four monitoring points of which any three points are not collinear in the high-temperature space; secondly, constructing a tetrahedral model based on the four points, dividing the four surfaces into six regions by perpendicular bisectors of three sides of each triangle, comparing temperature values pairwise, and determining high-temperature regions of the four surfaces; and finally, enabling the high-temperature areas of the four faces to extend to form prisms to intersect, and obtaining a space area where a heat source is located. The method is convenient to operate, not only can the temperature distribution condition of the goaf be detected, but also the heat source area can be obtained through inversion according to the temperature of the measuring points, the heat source positions of the underground coal mine goaf and other fire areas are accurately judged, and therefore fire prevention and timely treatment after a fire happen are facilitated.

Description

technical field [0001] The invention relates to the technical field of goaf temperature monitoring, in particular to a method for inversion of the position of a heat source in a high-temperature region of an underground goaf in a coal mine. Background technique [0002] Underground coal mines, coal spontaneous combustion is one of the disasters that affect the safe recovery of working faces, and gobs are areas where coal spontaneous combustion occurs frequently. Therefore, it is very important to monitor the temperature in the goaf. [0003] Since the goaf is in a closed space, it is impossible to measure the temperature of the inner space in real time. At present, the gas detection method is often used to invert the degree of coal spontaneous combustion in gobs in field operations, and corresponding fire control measures are taken based on the inversion results. However, when using this method, due to the influence of wind flow, mining and geological occurrence in the coa...

AI Technical Summary

Problems solved by technology

[0005] However, optical fiber temperature measurement technology is to lay optical fibers in gobs or fire-prone areas in advance, and use optical time domain reflection technology to measure the temperature of gobs in real time. Since optical fibers are generally laid on the coal seam floor, they are affected by the collapse of the coal seam roof and mine water. , this method often has problems such as the optical fiber is broken, the optical fiber or the temperature sensor is soaked, etc.

In addition, this method requires pre-embedded optical fibers, and for areas that have not been pre-embedded and have been on fire, the internal temperature cannot be measured

[0006] Infrared detection technology is only suitable for temperature measurement in areas with obvious surface temperature changes, and is not suitable for temperature detection in goafs under mines or abandoned roadways

By inserting a thermocouple into the borehole to measure the temperature, although the temperature of the fire space can sometimes be measured, the measured temperature points are limited. Due to the influence of the surrounding rock conditions of the borehole and the poor thermal conductivity of the porous medium in the goaf, this method is accurate. Poor sensitivity and sensitivity, and the measured temperature point is difficult to obtain the heat source position by ordinary numerical fitting method

Images