CN-121993143-A - On-site microwave-assisted drilling pressure relief system and simulation method

CN121993143ACN 121993143 ACN121993143 ACN 121993143ACN-121993143-A

Abstract

The application relates to the field of geotechnical engineering and mining engineering, discloses a field microwave-assisted drilling pressure relief system and a simulation method, and aims to solve the problems of difficult drilling of hard and brittle rock, serious abrasion of drilling tools, high surrounding rock disturbance risk and the like in deep mine, tunnel engineering and underground space development. The system comprises a scanning and positioning module, a microwave radiation module, a mechanical drilling module, a data acquisition module and a central control module. The method comprises the steps of importing a three-dimensional digital rock mass model, solving an equation set to calculate microwave absorption power density, simulating a non-uniform temperature field evolution process, establishing a thermal-mechanical coupling mode type prediction microcrack expansion, and generating a construction parameter optimization scheme. The method can realize high-precision digital reconstruction of the geometric form of the rock mass, directional focusing application of microwave energy, dynamic coordination and closed-loop control of a microwave radiation and mechanical drilling system, improve the overall rock breaking efficiency, reduce the abrasion and construction risk of drilling tools and provide scientific construction parameter optimization and decision support.

Inventors

CHEN DENGHONG
GUO SHAOBO
ZHANG ENDE
YANG LIU
SHI WEI

Assignees

安徽理工大学

Dates

Publication Date: 20260508
Application Date: 20260126

Claims (10)

1. An in-situ microwave assisted drilling pressure relief system, comprising the following components: the scanning positioning module is used for carrying out three-dimensional scanning on the target rock mass at a construction site, obtaining the surface space geometric information and texture characteristics of the target rock mass, and constructing a high-precision three-dimensional digital rock mass model; the microwave radiation module is used for directionally applying high-frequency electromagnetic energy to a rock target area according to the radiation parameters planned by the three-dimensional digital rock mass model so as to induce thermal stress concentration and micro-crack expansion in the rock; The mechanical drilling module is used for executing drilling operation in the rock mass area pretreated by microwaves, and the drilling path and the gesture of the mechanical drilling module are planned cooperatively by the central control module based on the three-dimensional model and the construction target; The data acquisition module is used for acquiring microwave power parameters, rock mass temperature fields, stress fields, drilling dynamics parameters and environmental parameters in the construction process in real time; And the central control module is used for carrying out centralized control and data fusion processing on the scanning positioning module, the microwave radiation module, the mechanical drilling module and the data acquisition module, executing an intelligent decision algorithm and realizing dynamic coordination and closed-loop regulation and control of the microwave radiation and mechanical drilling process.
2. The on-site microwave assisted drilling pressure relief system according to claim 1, wherein the scanning and positioning module comprises a lightweight point cloud scanning device which adopts a multi-sensor fusion structure and integrates a laser radar, a depth camera, an inertial measurement unit and a visual sensor to complete high-speed acquisition of rock mass surface space characteristics, and a low-overlapping point cloud registration algorithm is built in the scanning and positioning module.
3. The on-site microwave assisted drilling pressure relief system according to claim 1, wherein the microwave radiation module comprises a microwave source, a waveguide pipe, a circulator, a water load and an adjustable structural frame, wherein a radiation end of the microwave radiation module is connected with the adjustable structural frame through an integrated adjusting seat, and the adjusting seat has at least two rotational degrees of freedom, so that the pitch angle and the rotational angle of the radiation end in a three-dimensional space can be accurately adjusted.
4. The on-site microwave-assisted drilling pressure relief system according to claim 1, wherein said mechanical drilling module is of modular construction, and comprises a power unit, a transmission unit, a circulation unit, a control unit and a drilling tool unit; the drilling tool unit is a polycrystalline diamond compact drill bit or a hard alloy drill bit; the front end of the drill bit is provided with a guide structure made of microwave transparent materials or is embedded with a metal reflecting sheet.
5. The field microwave-assisted drilling pressure relief system of claim 1, wherein the data acquisition module integrates a multi-type sensor array comprising a power sensor, a thermal infrared imager, a fiber grating stress sensor, a displacement sensor, a torque sensor, a vibration sensor, and a temperature sensor.
6. The on-site microwave assisted drilling pressure relief system according to claim 1, wherein the intelligent decision algorithm carried by the central control module comprises a drilling resistance prediction model based on a long-term and short-term memory network and a multi-parameter collaborative optimization controller based on reinforcement learning; The multi-parameter collaborative optimization controller outputs the adjustment instructions of microwave power, radiation time, drilling speed and coolant flow in real time to form a closed-loop control loop by taking maximization of rock breaking efficiency and minimization of drilling tool abrasion as optimization targets.
7. The on-site microwave assisted drilling pressure relief simulation method is characterized by comprising the following steps of: S110, importing a three-dimensional digital rock mass model obtained by field scanning, and discretizing the model into finite element grids or discrete element particle sets with different material properties according to mineral composition, porosity and water content spatial distribution information of the rock mass; s120, based on electromagnetic field theory, solving a coupled Maxwell equation set on the discretization model, calculating the propagation, reflection and absorption processes of microwaves with specific frequencies and incidence angles in the rock mass, and distributing the microwaves through Poynting vectors Evaluating the microwave power density absorbed by each unit; s130, substituting the calculated microwave absorption power density as a transient heat source term into a heat conduction equation: ; Wherein, the For the density of the rock mass, The specific heat capacity is fixed for the rock mass, Is the thermal conductivity of the rock mass, In order to be able to determine the temperature, In order to be able to take time, Simulating the non-uniform temperature field evolution process of the rock mass under microwave irradiation by using the heat source power density of unit volume; S140, a thermal-force coupling model is established, a temperature field calculation result is used as a thermal strain load and is applied to a mechanical calculation domain, thermal stress field redistribution of a rock mass due to non-uniform thermal expansion is solved, and the cracking position and the initial expansion direction of microcracks are predicted based on a continuous damage mechanical model and a material anisotropy failure criterion; s150, simulating the expansion and penetration of a microcrack network and the formation process of macroscopic cracks under the combined action of thermal stress and external mechanical load by adopting a discrete crack model or a bonding particle model, and calculating the crack volume growth rate, the rock mass peak stress reduction rate, the equivalent elastic modulus change amount and the pressure relief influence area range in real time; S160, based on the quantitative evaluation indexes of the step S150, the system analyzes rock breaking efficiency and pressure relief effect under the combination of different microwave power, radiation time, incidence angle, drilling speed and cooling strategy, generates a construction parameter optimization scheme, and feeds back an optimal parameter set to a central control module of the on-site microwave auxiliary drilling pressure relief system for guiding actual construction.
8. The method for simulating in-situ microwave assisted drilling pressure relief according to claim 7, wherein in step S120, the Poynting vector is The calculation formula of (2) is as follows: , wherein, For the electric field strength vector of this point, The microwave power density absorbed by each unit is the negative value of Poynting vector divergence.
9. The method according to claim 7, wherein in step S130, the heat conduction equation is: ; Wherein, the For the density of the rock mass, The specific heat capacity is fixed for the rock mass, Is the thermal conductivity of the rock mass, In order to be able to determine the temperature, In order to be able to take time, Heat source power density per unit volume.
10. The method according to claim 7, wherein in step S160, the rock breaking efficiency is represented by a ratio of a drilling scale per unit time to total input energy, and the pressure relief effect is measured by a pressure relief influence area range and a stress reduction amplitude.

Description

On-site microwave-assisted drilling pressure relief system and simulation method Technical Field The invention belongs to the field of geotechnical engineering and mining engineering, and particularly relates to a field microwave-assisted drilling pressure relief system and a simulation method. Background Along with the development of deep mines, tunnel engineering and underground spaces, the deep mine tunnel engineering and underground space are continuously extended to the environment of high-stress and high-strength rock mass, and the hard and brittle rock mass is faced with the outstanding problems of low drilling efficiency, serious abrasion of drilling tools, high surrounding rock disturbance risk and the like in drilling and pressure relief construction. The traditional mechanical drilling mode relies on physical contact to crush rock mass, so that the energy consumption is high, the rock breaking efficiency is limited, rock burst or secondary damage is easy to induce under the condition of high ground stress, and the urgent requirements of modern deep engineering on efficient, safe and low-disturbance construction are difficult to meet. In recent years, the microwave rock breaking technology is widely focused on the non-contact energy input characteristic, and the microwave rock breaking technology generates local rapid temperature rise after electromagnetic waves are absorbed by a rock mass, so that thermal stress concentration and microcrack expansion are induced, and the rock mass strength is obviously reduced. However, the existing microwave rock breaking research is limited to static tests in a laboratory closed cavity, lacks system integration capability for complex field working conditions, cannot work cooperatively with actual drilling equipment, and severely restricts the engineering application of the technology. The core of the on-site microwave-assisted drilling pressure relief technology is to realize accurate application of microwave energy and dynamic cooperation of a mechanical drilling process. The technical direction aims to construct a composite rock breaking system integrating perception, decision and execution in a real construction environment by fusing three-dimensional perception, directional radiation and intelligent control means. The basic principle is that the geometric and structural information of the rock mass is obtained by utilizing on-site scanning, the optimal microwave radiation area and incidence angle are planned according to the geometric and structural information, the directional heating is implemented through the adjustable directional microwave device, the rock mass in the target area is weakened in advance, and then the efficient drilling is completed by the mechanical drilling tool, so that a cooperative mechanism of microwave presplitting and mechanical rock breaking is formed. The technical path can theoretically greatly improve the rock breaking efficiency, reduce the equipment loss and enhance the pressure relief effect, but the implementation is highly dependent on the tight coupling and the field adaptability design of the multiple modules. The prior art still has multiple systematic defects in the aspect of supporting the cooperative mechanism, namely the high-precision three-dimensional scanning and modeling capability suitable for severe construction environments such as dust, vibration, low illumination and the like is lacking, the surface morphology of a rock mass is difficult to accurately restore to guide microwave positioning, the microwave radiation device adopts a fixed beam direction, the radiation gesture cannot be automatically adjusted according to the geometric characteristics of the rock mass, so that the energy focusing deviation, the utilization rate is low and even the irradiation is invalid, the microwave system and the mechanical drilling system independently operate, the linkage control logic based on real-time feedback is not established, the dynamic matching of parameters such as power, drilling speed and cooling cannot be realized, and the field progression value method capable of comprehensively simulating the whole process of microwave heating, heat-force coupling, crack evolution and drilling dynamics is not available, so that the construction parameter optimization lacks scientific basis. The problems mentioned above cause that the microwave-assisted drilling technology is difficult to move from a laboratory to an engineering site, and a site microwave-assisted drilling pressure relief system and a matched simulation method integrating accurate sensing, directional radiation, cooperative control and digital simulation are needed to break through the technical bottleneck of efficient and safe construction of deep hard rock. Disclosure of Invention Aiming at the problems in the related art, the invention provides a self-adaptive closed-loop power flow optimization control method of a smart grid, so as to overcome the techn