Three-dimensional analog simulation test system for gas-liquid countercurrent in abandoned mine goaf

A three-dimensional analog simulation test system for gas-liquid countercurrent in an abandoned mine goaf, comprising:

• a three-dimensional analog simulation device configured to simulate an analog environment of gas-liquid countercurrent in an abandoned mine goaf, a gas supply system, an automatic water pressure control system, and a hydraulic loading system;
• wherein the three-dimensional analog simulation device comprises a reaction frame and a three-dimensional analog simulation chamber;
• the reaction frame comprises a beam, a base, and a column configured to connect the beam and the base;
• the three-dimensional analog simulation chamber is provided in the reaction frame;
• wherein analog materials corresponding to a formation condition of a mine to be simulated are uniformly laid in the three-dimensional analog simulation chamber upwardly from a bottom of the chamber;
• an excavation operation is carried out after the analog materials are dry;
• a fractured structure with a “vertical three-zone” and a “horizontal three-zone” is formed in the goaf after the excavation;
• wherein the vertical three-zone comprises a curved subsidence zone, a fractured zone and a caving zone;
• the horizontal three-zone comprises a coal seam support zone, a separation zone, and a re-compaction zone;
• the gas supply system comprises a gas supply pipe and a gas cylinder configured to supply gas to the gas supply pipe;
• the gas supply pipe is pre-embedded in the three-dimensional analog simulation chamber and arranged below the goaf;
• the gas supply pipe is uniformly provided with a plurality of first nozzles facing the goaf;
• the automatic water pressure control system comprises a buffer tank, a pressure sensor, a nitrogen cylinder, a water supply tank, a water pressure test pump, a water supply pipe and an electronic controller;
• a top of the buffer tank is connected to a first interface of a four-way joint, and a bottom of the buffer tank is connected to a first interface of a three-way joint;
• the pressure sensor is connected to a second interface of the four-way joint;
• the nitrogen cylinder is connected to a third interface of the four-way joint through a gas pipe;
• an inlet of the water pressure test pump is connected to the water supply tank through a first water pipe, and an outlet of the water pressure test pump is connected to a second interface of the three-way joint through a second water pipe;
• the water supply pipe is pre-embedded in the three-dimensional analog simulation chamber and arranged above the goaf;
• the water supply pipe is uniformly provided with a plurality of second nozzles facing the goaf;
• the plurality of second nozzles are connected to a third interface of the three-way joint through a third water pipe;
• a stop valve is arranged on the third water pipe between the water supply pipe and the three-way joint;
• the electronic controller is electrically connected to the pressure sensor and a circuit breaker of the water pressure test pump respectively, receiving a detected value of the pressure sensor and comparing the detected value with a preset value to control an opening or closing of the water pressure test pump;
• the hydraulic loading system comprises a bearing plate, a loading pressure head, a hydraulic pump, a hydraulic loading control cabinet configured to provide a pressure to the loading pressure head and control the pressure, and a motor configured to provide power to the hydraulic pump;
• the bearing plate is overlaid on a top of a rock strata mimic;
• the loading pressure head passes through a head mounting hole on the beam of the reaction frame and abuts against the bearing plate, and is connected to the hydraulic loading control cabinet through a first hydraulic pipe;
• the hydraulic pump is connected to the hydraulic loading control cabinet through a second hydraulic pipe.