Simulation Modeling Method Research Articles

The method of virtual bench tests conducting to analyze the vehicle technical characteristics compatibility to detect and prevent the risk of resonant phenomena in the sprung cab

BACKGROUND: A relevant issue when designing vehicles with multiple levels of suspension systems is collaborative operation of these systems, which ensures the required vehicle dynamics and smoothness parameters, as well as the absence of risk for the occurrence of resonance phenomena. The vehicle cab is a dynamic system with 6 degrees of freedom, so its oscillatory motions have a complex spatial character with the oscillation energies overflow from one direction to another. The solving of problems of the sprung cab dynamics should be conducted in a spatial nonlinear formulation, which makes it possible to take into account the phenomena of redistribution of oscillation energy between the directions of space. This approach can be put into operation with simulation modeling methods through creating a spatial virtual rig of the cab with a suspension system and modeling its dynamics with the application of appropriate external inputs.
 AIM: Development of the method of using virtual tests to analyze the compatibility of technical characteristics of the cab suspension system, the frame system and the primary vehicle suspension systems to detect and prevent the risk of resonant phenomena in the cab.
 METHODS: Building a virtual test rig of a vehicle cab as a multibody dynamics system of connected bodies in space, mounted at the movable vehicle frame with spring-dampers. Virtual tests are conducted by simulation modeling methods according to the method for analyzing nonlinear phenomena when spatial resonances occur in the secondary suspension system of a vehicle cab.
 RESULTS: The method of vehicle cab virtual tests conducting for analyzing oscillatory processes occurring in the cab, including resonances, using a virtual test rig in a multibody dyamics software package.
 CONCLUSION: The developed method ensures an ability to take measures to detect and prevent the risk of spatial resonance phenomena in the vehicle cab at all stages of the components design and the cab suspension systems study.

Research on simplified tire finite element modeling and simulation method

A simplified tire finite element model modeling and simulation method with high efficiency and accuracy is proposed to address the issues of poor efficiency and low accuracy in tire finite element simulation. Firstly, the detailed finite element model of the tire is established, and the viscoelastic material parameters are determined through theoretical analysis and simulation verification. Then, the Hyperelastic material parameters are obtained through cyclic Tensile testing, and finally, the static tire condition test verification is completed. Based on the established detailed finite element model of the tire, the influence of different rubber materials on the dynamic characteristics of the tire is studied. On this basis, simplified friction and structure models are proposed to complete the establishment of a simplified tire finite element model. The simulation results of lateral and longitudinal slip conditions are compared with experimental data by implanting a finite element friction model that considers slip velocity and contact pressure. Through simulation analysis, it was found that the tread compound has a significant impact on the dynamic characteristics of the tire, while other compounds have a relatively small impact. Simplifying the tire finite element model can significantly improve the efficiency of finite element simulation and reduce convergence issues. The comparison accuracy between the finite element model simulation results and experimental data is relatively high, with the average accuracy of longitudinal force, lateral force, and correction moment reaching 89%, 95%, and 81%, respectively. This verifies the correctness and effectiveness of the simplified tire finite element model modeling and simulation method. This method provides certain reference significance for improving the efficiency of tire finite element simulation and providing virtual matching between tires and the entire vehicle.

Diagnostics of inter-turn short circuits in phase stator windings of permanent magnet synchronous machines

BACKGROUND: Currently, electric buses are becoming more widespread in the segment of urban passenger transportation due to the absence of harmful emissions and low noise levels. Permanent magnet synchronous machines (PMSM) are widely used as a traction motor.
 One of the most promising methods of monitoring the technical condition of traction motors is diagnostics using monitoring tools installed on board of a vehicle. The advantages of such methods include the possibility of regular frequent condition checks (as opposed to much rarer diagnostics in stationary maintenance points) and a more rapid response to the development of identified malfunctions, which significantly reduces the cost of maintenance and repair of expensive equipment. The disadvantages include limitations associated with a shortage of layout space for the placement of diagnostic equipment, with the limited capabilities of on-board computer facilities for the transmission and storage of diagnostic information and with the complexity of computational procedures of built-in expert diagnostic systems.
 Concerning the types of operational failures of PMSMs, which are the most common and the most severe in terms of the cost of restoring operability, these are inter-turn short circuits in the stator windings, increased eccentricity of the air gap between the stator and the rotor, bearing damage, as well as damage of the mechanical gearbox coupled with the electric motor.
 AIM: Identification the diagnostic signs of inter-turn short circuits in the phase windings of a permanent magnet synchronous machine, helping to detect these malfunctions on board of route urban vehicles at an early stage.
 METHODS: A mathematical model of a permanent magnet synchronous machine with short-circuited turns of the phase winding, which makes it possible to study the behavior of the motor with a various number of short-circuited turns, has been developed.
 RESULTS: For the first time, the requirements for diagnostic features for the on-board diagnostic system of an urban electric bus, making it possible to detect inter-turn short circuits in the phase windings of traction electric motors at the early stages of the origin of a malfunction, are formulated.
 The main parameters of the process of digital registration of phase currents have been obtained, helping to do measurements and to transmit signals through the onboard information network of the electric bus.
 Using simulation modeling methods, it was found that the peak values of the linear spectrum of the total current vector are stable diagnostic signs that make it possible to detect inter-turn short circuits in the phase windings of traction motors at the early stages of the origin of the malfunction.
 CONCLUSION: The practical value of the study lies in the opportunity of using the proposed methods for diagnosing the technical condition of traction electric drive units in urban passenger electric transport.

Four-antenna amplitude direction finder: statistical synthesis and experimental research of signal processing algorithm

The subject of this study is the algorithms for measuring the angular positions of radio emission sources. The goal of this study is to develop an improved algorithm for signal processing in amplitude direction finders that will provide several unambiguous measurement angles at high steepness of the discrimination characteristic by combining measurements of systems with different widths of antenna patterns. The task: to develop an optimal signal processing algorithm for a four-antenna amplitude direction finding system, two antennas of which have a wide radiation pattern and the other two have a narrow one; to test the overall performance of the resulting algorithm by simulating the direction finder; to develop and conduct a study of an experimental model of a four-antenna direction finder, which includes two antennas with wide radiation patterns, two antennas with narrow radiation patterns, radio frequency paths, and a signal processing unit that implements the developed algorithm; to analyze the effectiveness and features of the application of the developed algorithm, and to compare the results of simulation modeling and experimental research. The methods used are statistical methods and optimal solutions for solving problems of statistical synthesis of signal processing algorithms in passive radio systems, computer simulation modeling methods, and experimental research methods. The following results were obtained. The algorithm for signal processing in a four-antenna direction finding system was synthesized using the maximum likelihood method. By simulation modeling, the overall effectiveness of measurement integration in multi-antenna amplitude direction finders was confirmed, and the peculiarities of the synthesized algorithm application were revealed, namely, the need to introduce additional proportionality coefficients into the measurement channels. During the experimental studies of the developed model of the direction finder, the results of the simulation modeling were confirmed. Conclusions. To determine the direction of radiation sources by amplitude direction finders, it is advisable to simultaneously use systems with wide and narrow antenna patterns, the measurements of which are combined by the proposed algorithm. This makes it possible to simultaneously expand the range of unambiguous measurement angles and increase the accuracy of measurements within the equal-signal zone. The disadvantage of using the algorithm is the nonlinear form of the obtained discrimination characteristics and the need to determine additional proportionality coefficients heuristically.

Distribution ofresourcesin the system of decentralized management

Purpose of work is optimization of processes in a decentralized system during resource distribution among consumers in conditions of its scarcity and incomplete a priori information. Methodology. To achieve the goal, analytical methods were used in combination with methods of simulation modeling of processes that determine the optimal mode of operation of the decentralized system. Research results. The problem of allocation of a limited resource is a typical problem of operations research and, if its parameters are known, it is solved as a conditional optimization problem. However, in a decentralized system, each of its constituent elements does not have complete a priori information about the parameters of the problem (of the entire system). In such a situation, lack of information, and in the extreme case, a complete lack of a priori information for each of the elements of the decentralized system must be filled with a posteriori information. This requires a coordinated strategy for the behavior of all elements of the system. Algorithms for the behavior of the decentralized system elements are proposed in this work, which provide an optimal solution of the problem through a certain number of management steps, which depends on the amount of initial information. Scientific novelty. A new algorithm for adaptive tuning of a decentralized system are proposed and investigated, which provides access to the optimal mode of its operation when distributing a limited amount of resources between consumers. Practical significance. Decentralized systems have a number of advantages compared to traditional management systems of different structures: increased survivability, significant reduction of communication equipment. Besides, in some cases, the use of decentralized systems is the only option. On the other hand, the emergence and development of modern small-sized means of processing information allows technically implementing rather complex computational algorithms for each element of the system. Studying and solving the problems of improving the efficiency of decentralized systems has an obvious practical significance.

Impacts of small and medium-sized reservoirs on streamflow in two basins of Southeast China, using a hydrological model to separate influences of multiple drivers

Study regionSoutheast coast of China Study focusThe reservoirs in southeast coast of China are mostly small due to the limitations of terrain. In order to analyze the impact of these densely distributed small and medium-sized reservoirs (SMRs) with lacking observation and operational data on runoff, this paper uses a hydrological model & scenario simulation method to separate the impacts of climate variability (CV), land use change (LUC) and SMRs group change on streamflow variation in two river basins of Southeast China. New hydrological insights for the region(1) The streamflow of two basins has changed greatly, with CV and SMRs change being the main influencing factors, while the impact of LUC was relatively small. The contribution rates of CV to the annual runoff change of three hydrological stations in two river basins were 90.19%, 61.75% and 26.64%; Contribution rates of SMRs changes were 9.34%, 37.24% and 71.04%, correspondingly. (2) The regulation of streamflow by SMRs changes led to a decrease in both annual and monthly runoff, which was due to the fact that the main functions of SMRs in this region are agricultural irrigation and domestic water supply. (3) The three-factor separation method based on hydrological modeling, which separated the cumulative effects of SMRs in the form of SMRs group, would be valuable for the study and management of watersheds with numerous SMRs and lack of observation and operational data.

Identification of Dual-Target Inhibitors for Epidermal Growth Factor Receptor and AKT: Virtual Screening Based on Structure and Molecular Dynamics Study.

Epidermal growth factor EGFR is an important target for non-small cell lung (NSCL) cancer, and inhibitors of the AKT protein have been used in many cancer treatments, including those for NSCL cancer. Therefore, searching small molecular inhibitors which can target both EGFR and AKT may help cancer treatment. In this study, we applied a ligand-based pharmacophore model, molecular docking, and MD simulation methods to search for potential inhibitors of EGFR and then studied dual-target inhibitors of EGFR and AKT by screening the immune-oncology Chinese medicine (TCMIO) database and the human endogenous database (HMDB). It was found that TCMIO89212, TCMIO90156, and TCMIO98874 had large binding free energies with EGFR and AKT, and HMDB0012243 also has the ability to bind to EGFR and AKT. These results may provide valuable information for further experimental study.

A Novel Framework Based on Integration of Simulation Modelling and Mcdm Methods for Solving Fms Scheduling Problems

A Novel Framework Based on Integration of Simulation Modelling and Mcdm Methods for Solving Fms Scheduling Problems

Parameter Optimization Design of the Commutation Circuit of a Hybrid DC-Current-Limiting Circuit Breaker

Aimed at the optimization design of the parameters of the commutation circuit of a hybrid DC-current-limiting circuit breaker (HDCCLCB), a parameter selection model considering the short-time withstand of the thyristor and the volume of the commutation circuit is proposed by simplifying the object, and the commutation circuit parameters were preliminarily obtained. In order to verify the correctness of the method of selecting the commutation circuit parameters, the circuit simulation model of the HDCCLCB was built. The experimental platform was built, and the breaking experiment was completed under the fault condition with the current rising rate of 20 A/μs. The correctness of the simulation model and parameter design method was verified by comparing the circuit model simulation results with the experimental results. In order to further optimize the parameters of the commutation circuit, a mathematical model for optimization design was established. Taking the maximum critical breakdown voltage under unit capacitance energy as the objective function, the arcing time before commutating and the current-limiting inductance and capacitance are enumerated to obtain the optimized commutation circuit parameters. By comparing this result with the result of the preliminary design, the objective function is improved by 20.7%, laying a solid foundation for further research and the development of current-limiting circuit breakers for medium-voltage DC systems.

APPLICATION OF THE STATISTICAL TESTING METHOD FOR SIMULATION MODELLING OF COMPLEX SYSTEMS

Problem statement. The study of the multicomponent systems’ operation is possible using statistical simulation models. In contrast to traditional mathematical modeling, in order to build the specified type of models, it is not necessary to obtain a mathematical formalization of the relationship between parameters in one form or another. The main condition is the ability of the model to reproduce the phenomena being modeled, while preserving their logical and temporal sequence and physical meaning. One of the most common methods of statistical simulation modeling is the method of statistical tests - the Monte Carlo method. The basis of this method is the repeated use of a random number generator to simulate the dynamics of processes occurring in the system. Based on the obtained iterations, statistical criteria for evaluating the obtained results are calculated, which makes it possible to conduct a preliminary analysis of the physical processes under investigation and draw conclusions about the relationship between the parameters included in the model. Thus, taking into account the general principles of these building simulation models, it is advisable to use them to study a number of applied materials science problems, for example, to describe the influence of external factors on the structural state of the material. The purpose of the article. Application of statistical simulation modeling by the method of statistical tests (Monte Carlo method) for the study of physical processes that occur in complex systems. Conclusion. Using the Monte Carlo method, a simulation model of the relationship between the technological modes of welding and the parameters of the structural state of low-carbon low-alloy steel 09Г2С was obtained. The obtained simulation model is presented in the form of a matrix containing the results of statistical tests. The analysis of the obtained statistical indicators made it possible to carry out a preliminary analysis of the relationship between technological modes of welding and the corresponding structural state of low-carbon low-alloy steel 09Г2С. Preliminary evaluation of the obtained simulation model was carried out by analyzing active constraints of the type of inequalities. The conducted set of studies proved the obtained data adequacy.

Method for evaluating fairness of electricity tariffs with regard to income level of residential buildings

Modern advancements in energy technology, such as smart meters and renewable power generation, have contributed to the increasing penetration of time-variable electricity pricing plans. Under such plans, consumers experience a higher financial burden for consuming electricity when overall demand is high. Lower-income households may be disproportionately burdened by the transition to time-variable pricing because they tend to have less efficient homes and appliances, which may necessitate greater overall electricity consumption, especially during peak times. The goal of this work is to create a broadly applicable framework for evaluating the fairness of utility pricing plans. The proposed slope analysis method examines the distribution of a fairness metric across income levels in order to determine the level of fairness exhibited by a pricing plan. This work utilizes three fairness metrics, which are based on total household electricity bill and income, as a proof-of-concept for the slope analysis method and assesses their viability for fairness research. The proposed method also utilizes household energy models to represent various income levels for any location with sufficient data. The framework is evaluated using simulated households across 5 income levels and 3 climate zones in the United States. Fairness metrics are applied to the utility bills calculated under Real-Time Pricing and existing tariffs offered at each location. The proposed fairness evaluation method provides a quantitative measure of fairness and is broadly applicable across location and pricing plans. The metric based on the change in percentage of income spent on utilities considers the relative financial burden on households, which results in the slope analysis method outputting conclusive, accurate fairness determinations more often than the other examined metrics. The results demonstrate disparity in energy affordability, and the proposed slope analysis and model simulation methods provide a readily transferable testbed to evaluate energy policy equity.

Improving Electricity Efficiency by DC Power Transmission: A Case Study in Vietnamese Mining

The exploitation and use of fossil fuels, including coal, to promote socio-economic development is taking place firmly, including in Vietnam. Vietnam’s mining industry is getting deeper and deeper, and the degree of mechanization is increasing, making electricity consumption even bigger. The efficient use of electricity to reduce the power consumption per ton of mined coal significantly improves labor productivity, reduces environmental emissions, and moves towards sustainable socio-economic development. For mining in Vietnam today, electricity is still transmitted by AC, causing undesirable consequences that reduce the efficiency of electricity use. To overcome the above problems, it is possible to use DC power transmission. The content of the article analyzes the use of DC power transmission in mining in Vietnam based on simulation modeling methods using Matlab-Simulink software to improve power efficiency, reduce environmental emissions, and move towards sustainable development.

People flow management in a healthcare facility through crowd simulation and agent-based modeling methods

The study investigates the optimization of user flow and space management in a hospital located in Turin by simulating activities and patient flows of the blood drawing center. The simulation aims to verify the maximum number of people allowed to occupy the spaces simultaneously, manage user flows, and verify compliance with COVID-19 pandemic restrictions. Pedestrian Dynamics, supported by Building Information Modeling (BIM) methods, and NetLogo are used to simulate and optimize user flow and space management relying on crowd simulation and Agent-Based Modeling. Patients’ movements and hospital activities are modeled to identify bottlenecks, crowded situations, and other issues. The methodology also allows the comparison of the two selected tools via the two simulations that are set with equal parameters. The results of the simulations enabled the analysis of current conditions and the testing of scenarios and hypotheses without inconveniencing users and interrupting hospital activities. Some improvements in space and people flow management could be proposed, e.g., distributing patients’ entries over the center opening times via an online booking system and modifying room functions. The proposed improvements support the facility managers to avoid, or at least minimize, crowded situations during which is not possible for patients to comply with COVID-19 pandemic restrictions, while minimizing layout changes and consequently the costs and efforts of implementing the changes. The proposed methodology will enable better management of future emergencies in healthcare facilities. The tool comparison will support future studies on simulation tool selection according to simulation and stakeholder needs.

A Widely Applicable Modeling and Efficient Simulation Method for Power Electronics Grids Based on Unit Switching Circuits

As an essential part of modern power systems, power electronics have improved system performance. They also brought new dynamic and transient problems and posed significant challenges to precise and efficient simulation. Traditional modeling and solving methods fail to balance between the simulation accuracy and efficiency, and they are not flexible enough to adapt to converters with various new topologies. This article proposed a widely applicable modeling and simulation method based on the unit switching circuit that greatly promote the simulation efficiency and modeling simplicity by converting switching circuits into constant sub-grid equations with injection functions. Critical issues for engineering applications, such as the blocking state and the triggering deadband of converters, were also discussed and addressed by boundary balance and conduction path estimation. The error and stability of the solving method were qualitatively analyzed, with further discussions on the validity and numerical features. Several cases, including common and general cases and a real project of power electronic microgrid, tested and verified the accuracy, generalization ability, and efficiency of the proposed method.

Optimal Allocation of Territorial Space in the Minjiang River Basin Based on a Double Optimization Simulation Model

The unequal distribution of territorial space resources stands out as a leading cause of the human–land contradictions and environmental degradation. These issues are especially pronounced in the Minjiang River Basin, which exhibits significant regional disparities. In pursuit of solutions to these pressing problems and the identification of sustainable developmental pathways, this study presents an innovative territorial space double optimization simulation model. This model integrates quantity structure optimization and distribution pattern optimization, in order to comprehensively consider the optimization of territorial space allocation and build a new territorial space pattern for the Minjiang River Basin in 2030. On this basis, we employed the Patch-generating Land Use Simulation (PLUS) model and scenario analysis method to design the double optimization scenario and natural development scenario. By comparing these two scenarios, and calculating the ecological benefits (EB), economic benefits (ECB), carbon storage (CS), and comprehensive benefits (CB) achieved in different scenarios, the validity of the double optimization model was fully verified. The results indicated that: ① the loss of sub-ecological space (PeS) under the natural development scenario was significantly larger than that under the double optimization scenario, and the loss should be mainly attributed to the large expansion of production space (PS) and living space (LS); ② the area of ecological space (ES) has reduced since 2020, but less area was lost and the retention rate was higher under the double optimization scenario; ③ the natural development scenario made the research region gain more ECB, but it also resulted in the loss of more EB and CS, whereas the Minjiang River Basin under the double optimization scenario was able to effectively balance the relationship among the three, thus achieving the best CB. The research findings provide strong scientific support for alleviating the human–land contradictions, protecting the ecological security in the basin, and promoting the sustainable development of the region.

Investigation of saturation levitation force and optimization of permanent magnet guideway based on multi-seeded superconducting bulks model

After more than 20 years of research, the superconducting maglev has advanced to the engineering research stage. In engineering applications, multi-seeded superconducting bulks have been widely used in high-temperature superconducting (HTS) maglev systems, but there remains a deficiency in terms of the theoretical model description of multi-seeded superconducting bulks. In this paper, the fully coupled, partially coupled, and uncoupled models of the multi-seeded superconductor are presented to simulate HTS multi-seeded bulk. Then, the levitation performance and trapped field of three kinds of HTS bulks were experimentally tested, revealing a saturation levitation performance on the permanent magnet guideway (PMG). Therefore, the levitation force and trapped field of HTS bulks with different critical current density are further studied by 3D simulation. Taking the 90% and 95% of the maximum levitation force as the benchmarks, the corresponding critical current density of HTS bulks are respectively 4.6 × 108 A m−2 and 6.1 × 108 A m−2. Further, a mapping coupled boundary method was adopted to automatic optimize the PMG to increase the levitation force above the PMG. After optimization, the levitation force under a unit of the permanent magnet is increased by 19%, while the maximum levitation force above multi-period Halbach PMG is increased by 9.23%. This study provides a general multi-seeded superconducting bulk simulation model and levitation force optimization method, which can serve as a reference for selecting suitable superconducting bulk.

Experimental and numerical study on fatigue damage evolution of Q690D welding details

Steel structures are widely used in various types of structures, and welding details, which are fatigue-prone constructions, are typically utilized in steel constructions. In this study, regarding the high cycle fatigue performance and fatigue damage evolution behaviors of high strength steel welding details, experimental and numerical studies have been carried out on two typical types of Q690D high strength steel welding details, including butt-weld connections and cruciform load-carrying fillet weld (CLFW) connections. High cycle fatigue tests have been conducted, SN curves based on effective notch stress have been established and compared with the suggested curves in IIW specification, showing that FAT200 is more suitable for fatigue evaluation of high strength steel welding details. Fatigue damage evolution model and numerical simulation methods for Q690D welding details based on effective notch stress and continuum damage mechanic have been established and validated. Damage evolution analysis of welding details has been conducted based on the proposed numerical simulation method. The simulation method enables accurate characterization of fatigue damage locations.

ANALYSIS OF DYNAMICS OF VOLUME HYDRAULIC POWER STEERING SELF-PROPELLED TRACTOR CHASSIS

Goal. Analysis of the dynamics of the hydraulic fluid power steering drive of the wheeled tractor self-propelled chassis СШ2540 by simulating the operation of a hydraulic cylinder with a one-sided rod for moving the steering trapezoid when turning the wheels and studying the change in the pressure of the working fluid and the movement of the hydraulic cylinder rod under different load modes. Research methodology. The method of simulation modeling is used, when the variables describing the behavior of the steering hydraulic cylinder are determined by certain load algorithms and operating fluid flows, and are described by differential equations. The differential equations that determine the pressure of the working fluid in the cavities of the hydraulic cylinder and the movement of its rod when the working fluid is fed into the piston or rod cavity are based on the laws of mechanics, the principle of the continuity of the flow of the working fluid and its compressibility. The VisSim package of application programs was used for modeling according to the proposed methodology. The changes of the parameters in the hydraulic cylinder of turning the wheels when they are shifted from the task of the control action in the form of an increase in the external load and the flow of the working fluid in the output channels of the metering pump overcome by the hydraulic cylinder were studied. The influence of the modulus of elasticity of the working fluid, which decreases when it is saturated with undissolved air, was also investigated. The results. When starting the hydraulic steering drive, i.e. when turning the steering wheel from its neutral position, depending on the external load and the intensity of the driver's work at the wheel, oscillatory processes take place in the hydraulic cylinder cavities, which can significantly exceed the working pressure. The results of the research give a reason to conclude that it is necessary to study the nature of the increase in the flow rate and pressure of the working fluid on a full-scale sample of the tractor chassis metering pump, i.e. by replacing the flow rate simulation with its actual value. Setting the loading time and flow rate of the working fluid using the map-VisSim unit is more convenient than setting it with analytical expressions, as it makes it possible to simulate different acceleration rates of the hydraulic cylinder and, if necessary, to control the stationary mode of the steering wheel in the neutral position.

Physical modeling of complex lithofacies volcanic edifices and seismic characteristics

Abstract The Songnan fault basin contains a significant distribution of basaltic volcanic rock structures, and serves as one of the primary types of reservoir in the area. Volcanic formations exhibit notable distinctions when compared to conventional oil and gas reservoirs, and the precise seismic response mechanism of these formations remains uncertain. Hence, it is imperative to investigate the seismic response mechanism of volcanic formations to enhance the geophysical characterization capability of oil and gas reservoirs composed of igneous rock. The seismic physical simulation model method is used to obtain dependable data for investigating the seismic response mechanisms of volcanic structures. This is achieved by constructing intricate physical models of rocks and volcanic structures. Our team focused on the development of materials and processes for accurately modeling various rock and volcanic structures, and we successfully designed and produced a three-dimensional physical model representing volcanic structures in the Chaganhua area. Furthermore, we conducted thorough data acquisition and analysis to examine the seismic response characteristics and sensitive properties of different geological bodies. We improved the accuracy of identifying different lithofacies of volcanic rocks by extracting different seismic attributes. This study presents a reliable approach for elucidating the seismic response mechanism of intricate rock and volcanic formations. It can also serve as a valuable resource for processing and interpreting seismic data in the specific study region. The conclusion that weak seismic reflection signals in volcanic rocks are effective signals rather than noise could be more conducive to accurate analysis and description of volcanic structures.

Study on reasonable loading mode of small-scale roadway model and its application in mining engineering

The small-scale roadway model is often used in the fine simulation of mining engineering. The determination of the structure and load conditions of the model has an important influence on the accuracy of the simulation. In this paper, a large-scale stratum model and a small-scale roadway model are established by using finite element method. The optimal loading mode of the roadway model and its applicability under different roof-sidewall stiffness ratios are studied. The simulation accuracy of the roadway model is quantitatively evaluated by comparing the distribution laws of stress field and strain field with those of the stratum models. Under the same roof-sidewall stiffness ratio, the similarity between the simulation results of the roadway model and the stratum model under displacement load is much higher than that under stress load. Under the same load mode, the stress and strain similarity between the stratum model and roadway model increases with the increase of the roof-sidewall stiffness ratio. Furtherly, the simulation application of the roadway drilling pressure relief is carried out. Compared with the large-scale stratum model with small-size elements, the small-scale roadway model under displacement load also shows obvious stress transfer after drilling pressure relief, while it has faster computational efficiency. Finally, a small-scale roadway model simulation method suitable for surrounding rock disaster occurrence mechanism and control is proposed.