The simulation experiment method of coal body fractured by ultrasonic and hydraulic fracturing in underground coal mine

Abstract

The invention discloses an ultrasonic wave and hydrofracture compound coal-body fracturing simulation device and method for an underground coal mine. The ultrasonic wave and hydrofracture compound coal-body fracturing simulation device comprises a closed tri-axial pressurizing device, an ultrasonic wave and hydrofracture compound fracturing device, a gas extracting and injecting device and a monitoring and controlling device. The ultrasonic wave and hydrofracture compound fracturing device comprises an ultrasonic wave fracturing device and a hydro-fracturing device, and the gas extracting and injecting device comprises a vacuum air pump and a gas injecting cylinder with a pressure gauge. A coal sample is put in the tri-axial pressurizing device, and the ultrasonic wave and hydrofracture compound fracturing device enables the ultrasonic wave fracturing device and the hydro-fracturing device to be respectively connected with the coal sample in the closed tri-axial pressurizing device through an h-shaped steel pipe. The vacuum air pump in the gas extracting and injecting device and the gas injecting cylinder with the pressure gauge are respectively connected with the coal sample in the closed tri-axial pressurizing device. The monitoring and controlling device is connected with the coal sample in the closed tri-axial pressurizing device. The ultrasonic wave and hydrofracture compound coal-body fracturing simulation device can really and accurately simulate the ultrasonic wave and hydrofracture compound coal-body fracturing process of the underground coal mine.

Description

technical field [0001] The invention relates to an experimental simulation device for combined fracturing of coal bodies by ultrasonic waves and hydraulic fracturing, in particular to a simulation device and method for combined fracturing of coal bodies by ultrasonic waves and hydraulic fracturing in coal mines. Background technique [0002] Gas is the main cause of frequent and serious coal mine accidents in my country. With the increase of coal mine depth and single well output, the amount of gas gushing out is increasing. important problem. At present, gas drainage is one of the most effective measures to solve gas disasters. my country's geological conditions are complex, and the gas pressure of coal seams is high and most of them are low-permeability coal seams. With the increase of mining depth, the influence range of commonly used measures such as hydraulic fracturing, hydraulic slits and pre-splitting blasting will be limited. A single technology After the measures a...

AI Technical Summary

Problems solved by technology

There are many ideal assumptions in theoretical analysis and numerical simulation, which are too different from the actual occurrence state of underground coal seams; directly going to coal mines for underground experiments is not only costly and dangerous, but also the gas pressure, coal quality, and stress state of each coal mine are also single , the chance probability is too high

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