CN-121997814-A - Reservoir landslide surge numerical simulation method and system

CN121997814ACN 121997814 ACN121997814 ACN 121997814ACN-121997814-A

Abstract

The invention discloses a reservoir landslide surge numerical simulation method and system, and relates to the technical field of geological disaster simulation, wherein the method comprises the specific steps of data acquisition and modeling, coupling model construction and correction, landslide mode parameter configuration, coupling simulation operation execution and simulation result output; according to the invention, through constructing a CFD-DEM coupling model, an organic connection is established between a DEM discrete unit model of a solid part and a CFD fluid mechanical model of a flow field part through a fluid-solid interface mechanical transmission formula, the CFD fluid mechanical model introduces a porosity correction mechanism, corresponding porosity values are distributed by actually measuring a rock-soil body sample and dividing a porosity region according to differences of different region rock-soil body types, densities and crack development of a landslide body, and a flow field control equation is corrected through the porosity of each region, so that the targeted optimization of the CFD fluid mechanical model is realized, and the mechanism can truly restore the restriction and guide effects of the porosity on fluid flow.

Inventors

BAO YIDING
ZHOU XIN
NING PO

Assignees

中国科学院、水利部成都山地灾害与环境研究所

Dates

Publication Date: 20260508
Application Date: 20260109

Claims (9)

1. A numerical simulation method for landslide surge of a reservoir is characterized by comprising the following specific steps: Data acquisition and modeling, namely acquiring geological topography data of a reservoir bank slope by adopting actual measurement of an unmanned aerial vehicle, and constructing a three-dimensional geological model based on the acquired geological topography data; constructing and correcting a coupling model, namely constructing a CFD-DEM coupling model by adopting CFD and DEM based on a three-dimensional geological model, correcting a flow field part by adopting a CFD fluid mechanical model and introducing porosity parameters, and adopting a DEM discrete unit model in a solid part; Landslide mode parameter configuration, namely according to a three-dimensional geological model, corresponding mechanical parameters, motion characteristic parameters and boundary conditions are configured for two modes of landslide of the bulk body and collapse of the dangerous rock body; The coupling simulation operation is executed, namely a three-dimensional geological model, a CFD-DEM coupling model and configuration parameters are input into a simulation system together, the CFD-DEM coupling model is started to carry out the circulating coupling operation, and the whole process of coupling action among a landslide body, pool water and air, surge generation, propagation, climbing and attenuation is simulated; And outputting simulation results, namely receiving surge data generated by coupling simulation operation, and outputting data of a surge movement process, a surge height and an influence range.
2. The method for simulating the landslide and surge values of the reservoir according to claim 1, wherein in the data acquisition and modeling, the geological topography data comprise the topographic topography data of the reservoir bank, the physical and mechanical parameters of a rock and soil body, the geomechanical characteristic data of the rock and soil body, the depth of reservoir water, the distribution range of the landslide body and the boundary characteristic data, the three-dimensional geological model is constructed through three-dimensional software, the actual measured geological topography data are introduced in the construction process for calibration, and the three-dimensional geological model comprises the spatial distribution information of the landslide body, the reservoir water and the air.
3. The reservoir landslide surge numerical simulation method of claim 1 is characterized by comprising the specific steps of constructing a CFD-DEM coupling model based on geomechanical characteristic data of a rock-soil body in a three-dimensional geological model, constructing a flow field model foundation frame for representing the behaviors of reservoir water and air fluid by adopting a CFD technology, wherein the flow field model foundation frame is a core foundation structure of the CFD fluid mechanical model, constructing a discrete unit model structure for representing the solid mechanical behaviors of the landslide body by adopting a DEM technology, wherein the discrete unit model structure is a core structure of the discrete unit model of the DEM, and setting a data interface for mechanical transmission through a fluid-solid interface mechanical transmission formula, quantifying interaction force between fluid and solid, wherein the fluid-solid interface mechanical transmission formula is as follows: , wherein, For the interaction force between the fluid and the solid, In order to couple the stiffness coefficients of the spring, In the case of a fluid pressure, In order for the contact area to be a contact area, Is the interface friction coefficient Is a solid state shear stress, and the shear stress, In order to shear the area of action, Is determined by fitting the interface mechanics measured data of the rock-soil body and the reservoir water, Is determined by fluid-solid contact interface geometry information in a three-dimensional geologic model.
4. The reservoir landslide surge numerical simulation method of claim 1, wherein in the coupling model construction and correction, a flow field control equation of a CFD fluid mechanical model is corrected by introducing porosity parameters, and the CFD fluid mechanical model optimization is completed, specifically, porosity detection is carried out on a rock-soil body sample obtained through actual measurement of an unmanned aerial vehicle, porosity data are obtained through detection, a plurality of areas are divided according to the rock-soil body types and structural differences of different areas of a landslide body, corresponding porosity numerical values are distributed for the areas, and the CFD fluid mechanical model optimization is completed by utilizing the porosity of each area through the porosity correction flow field control equation, wherein the porosity correction flow field control equation is as follows: , wherein, In order for the porosity to be the same, As a fraction of the volume of the fluid, In order to be able to take time, Is the fluid velocity.
5. The reservoir landslide surge numerical simulation method according to claim 1, wherein in landslide mode parameter configuration, according to landslide body types reflected by a three-dimensional geologic model, parameters are configured according to two modes of landslide of a particulate body and dangerous rock body collapse, wherein the corresponding mechanical parameters and motion characteristic parameters are configured according to the particulate body landslide mode, the mechanical parameters comprise inter-particle friction coefficients and particle bonding strength, the motion characteristic parameters comprise stacking angles and initial motion speeds, the corresponding mechanical parameters and motion characteristic parameters are configured according to a dangerous rock body collapse mode, the mechanical parameters comprise rock integrity coefficients, fracture surface shear strength and elastic modulus, the motion characteristic parameters comprise initial crack distribution, boundary conditions of the two modes are uniformly configured, the boundary condition parameters comprise reservoir water density, dynamic viscosity, air resistance coefficient and bank slope constraint strength, calibration of the mechanical parameters, the motion characteristic parameters and boundary condition parameters is finally completed through landslide mode parameter calibration formulas, and final configuration parameters are obtained through fusion of actual measurement parameters and historical formula parameters, and landslide mode parameter calibration is as follows: , wherein, In order to achieve the final configuration parameters, In order to actually measure the geological parameters, As a result of the historical landslide case parameters, And And as a weight coefficient, determining through similarity analysis of the geological condition of the target reservoir and the historical landslide case, wherein the similarity is determined through a geological structure, a rock-soil body type and a hydrologic environment.
6. The method for simulating the landslide and surge values of the reservoir according to claim 1, wherein the specific steps of executing CFD-DEM coupling model circular coupling operation in the coupling simulation operation execution are that displacement, speed and stress data of a landslide body in a DEM discrete unit model are calculated through a DEM technology, the displacement, speed and stress data of the landslide body are input into an optimized CFD fluid mechanics model, flow field change data of reservoir water and air and reaction force data of the landslide body are determined, the reaction force data are fed back to the DEM discrete unit model, the mechanical state of the landslide body is updated, the next round of calculation is started, the iterative convergence state is judged through an iterative convergence judgment formula, simulation operation accuracy is guaranteed, and the iterative convergence judgment formula is that: , wherein, In order for the energy to be of an error, For the total energy of the system for the nth iteration, For the total energy of the system for iteration n-1, And determining the convergence threshold according to the landslide surge simulation standard.
7. The method for simulating the landslide and surge values of the reservoir according to claim 1, wherein the method is characterized by further comprising the step of data monitoring, wherein a plurality of monitoring nodes are arranged at key positions of a landslide body motion path, different depth sections of reservoir water and sensitive areas of a bank slope, the motion parameters of the landslide body displacement, speed and stress of each monitoring node, the reservoir water flow speed, pressure and surge height data are collected in real time, and the collected monitoring data are recorded after each round of iterative operation is completed.
8. The method for simulating the landslide surge numerical value of the reservoir according to claim 1, wherein in the simulation result output, the specific step of outputting data is that the output comprises two forms of a chart and a standardized data file, the chart comprises a surge motion track time sequence chart, different section surge height distribution charts and coastal influence range schematic diagrams, and the data file comprises original acquired data of each monitoring node and processed surge characteristic parameters.
9. A reservoir landslide surge numerical simulation system suitable for the reservoir landslide surge numerical simulation method as set forth in any one of claims 1 to 8, characterized in that the system comprises: The data acquisition and modeling module acquires geological topography data of the reservoir bank slope by adopting actual measurement of the unmanned aerial vehicle, and constructs a three-dimensional geological model based on the acquired geological topography data; The coupling model construction and correction module is used for constructing a CFD-DEM coupling model by adopting CFD and DEM based on a three-dimensional geological model, correcting a flow field part by adopting a CFD fluid mechanical model and introducing porosity parameters, and adopting a DEM discrete unit model in a solid part; the landslide mode parameter configuration module is used for configuring corresponding mechanical parameters, motion characteristic parameters and boundary conditions for two modes of landslide of the bulk body and collapse of the dangerous rock body according to the three-dimensional geological model; The coupling simulation operation execution module inputs the three-dimensional geological model, the CFD-DEM coupling model and the configuration parameters into a simulation system together, starts the circulating coupling operation of the CFD-DEM coupling model, and simulates the coupling effect among a landslide body, pool water and air and the whole process of surge generation, propagation, climbing and attenuation; And the simulation result output module is used for receiving the surge data generated by the coupling simulation operation and outputting the data of the surge movement process, the surge height and the influence range.

Description

Reservoir landslide surge numerical simulation method and system Technical Field The invention relates to the technical field of geological disaster simulation, in particular to a reservoir landslide surge numerical simulation method and system. Background The reservoir landslide is a common geological disaster in the field of hydraulic engineering, and after the landslide body is quickly filled with water, strong surge can be caused, and the surge has the characteristics of high propagation speed, wide influence range and high damage strength, is extremely easy to impact reservoir dams, submerged coastal residents and infrastructure, forms serious threat to the safe operation of the hydraulic engineering and the safety of surrounding life and property, and along with the expansion of the construction scale of the hydraulic engineering and the improvement of the ecological protection requirement, the whole process of the generation, propagation, climbing and attenuation of the surge is accurately mastered, scientific basis is provided for the establishment of disaster risk assessment and protection measures, and the reservoir landslide is an urgent requirement in the field of reservoir disaster prevention. However, the landslide-river blockage-dam blockage-flood breaking disaster chain simulation method disclosed by the publication No. CN118296979A covers the whole process from river blockage to dam blockage, but adopts a single fluid mechanics model to simplify the landslide debris flow into a continuous medium and simulate the landslide debris flow based on a depth integral averaging method, and has the defects that firstly, the model does not realize real coupling of solid motion and fluid dynamics, the interaction mechanism between the landslide body after entering water and the air is difficult to accurately simulate, secondly, the influence of a rock-soil body pore structure on the fluid motion is not considered in the flow field simulation, so that the evolution distortion under the complex geological condition is caused, thirdly, the parameter system lacks the targeted adaptation of the mechanical characteristics of different landslide types, the accuracy of the simulation result is influenced, and fourthly, the simulation process lacks the real-time monitoring and iterative convergence control, and the calculation stability and the result reliability are insufficient. Therefore, a reservoir landslide surge numerical simulation method and a system are developed. Disclosure of Invention The invention aims to make up the defects of the prior art and provides a reservoir landslide surge numerical simulation method and a system, the invention establishes an organic connection between a DEM discrete unit model of a solid part and a CFD fluid mechanical model of a flow field part through a fluid-solid interface mechanical transmission formula by constructing a CFD-DEM coupling model, the CFD fluid mechanical model introduces a porosity correction mechanism, solves the technical pain point that the traditional flow field simulation ignores the structural difference of a rock-soil body, aims at the differences of the rock-soil body type, the compactness and the crack development of different areas of the landslide body, distributes corresponding porosity numerical values by actually measuring a rock-soil body sample and dividing a porosity area, corrects a flow field control equation by using the porosity of each area, the method has the advantages that the specific optimization of the CFD fluid mechanics model is realized, the restriction and guide effect of the apertures on fluid flow can be truly reduced by the mechanism, the flow velocity distribution, pressure change and two-phase interface evolution law of the reservoir water and the air can be accurately calculated, meanwhile, the DEM discrete unit model divides units with different particle diameters according to the particle composition characteristics of the landslide body, the discontinuous deformation and the movement law of the landslide body are reduced through the contact, collision, sliding and separation behaviors among particles, the flow field disturbance generated by the movement of the landslide body and the mechanical feedback of the flow field reaction on the landslide body are formed into a complete closed loop by coupling the two, the dynamic interaction process among the landslide body, the reservoir water and the air is clearly reproduced, and the simulation result is more fit with the actual geological evolution law. The invention provides a method for simulating the numerical value of the surge of a landslide of a reservoir, which aims to solve the technical problems and comprises the following specific steps: Data acquisition and modeling, namely acquiring geological topography data of a reservoir bank slope by adopting actual measurement of an unmanned aerial vehicle, and constructing a three-dimensional geological model based