Set Of Design Parameters Research Articles

Comparative assessment and optimization among several plenum shapes and positions for the forced air-cooled battery thermal management system

Plenum shape and position play a significant impact on the heat dissipation performance of battery pack with air-cooled structure. However, the existed plenum shape and position are simple. In this work, four different plenum shapes (slanted, convex, concave and stepped) of the battery thermal management system (BTMS) are designed. Then the influences of plenum shapes and positions (at the inlet, outlet, and inlet & outlet) on the heat dissipation performance of the battery are investigated, respectively. Subsequently, a single factor analysis is performed to obtain the range of the design parameters (Hin, Hout, Rin and Rout) in Design 6. Finally, a multi-objective optimization of Design 6 is carried out to further improve the thermal performance of BTMS. Numerical results demonstrate that: 1) For the significant improvement of the cooling ability, convex plenum is at the inlet & outlet whereas other shape ones are all at the inlet. 2) No matter where it is at the inlet, outlet, or inlet & outlet, the convex plenum achieves the excellent cooling effect in Z- and U-type air-cooled structures. 3) Design 6 (convex plenum at the inlet & outlet) exhibits the best cooling ability among all plenum shapes and positions. 4) The design parameters of the optimized Design 6 are Hin = 17.9 mm, Hout = 19 mm, Rin = 2100 mm and Rout = 2000 mm, and the maximum temperature and temperature difference respectively achieve a 35.06 % (18.921 K) and 76.98 % (19.923 K) reduction under such optimized design parameter settings in comparison with those of the benchmark (Design 9).

Research on Summer Indoor Air Conditioning Design Parameters in Haikou City: A Field Study of Indoor Thermal Perception and Comfort

Escalating global climate change and the intensification of urban heatwaves have led to an increase in summer air conditioning cooling energy consumption. This phenomenon is particularly critical in tropical regions, as it may trigger an energy crisis. The rational setting of indoor thermal design parameters can help conserve energy to the maximum extent while ensuring thermal comfort for occupants. This study selected Haikou City, a unique tropical city in China, as the research location. Indoor environment measurements and a questionnaire survey were conducted with participants, and the outdoor thermal environment sensitivity, population attributes and differences in thermal sensation, thermal neutral temperature, and comfort range were calculated and analyzed. The following results were obtained. Based on the overall population, long-term residence, and temporary residence classification, the indoor thermal comfort needs of residents in tropical cities in Haikou were effectively identified. The actual thermal neutral temperature of the overall population is 25.7 °C, and 90% of the acceptable thermal comfort temperature range is 23.2 °C–28.0 °C. The actual thermal neutral temperature of the regular residents is 27.3 °C, and 90% of the acceptable thermal comfort temperature range is 23.3 °C–31.4 °C. The actual thermal neutral temperature of the temporary population is 25.5 °C, and 90% of the acceptable thermal comfort temperature range is 23.0 °C–28.0 °C. These research results have an important reference value for improving the setting of the temperature of air conditioning in tropical areas in summer and further reducing energy consumption, which is conducive to sustainable development.

Theoretical analysis and simulation of FTIR spectrometer based on rotating double-sided reflective mirror

In this study, the FTIR spectrometer-based rotating double-sided reflective mirror (RDRM) is presented. By introducing the RDRM and corner reflector, an optical path difference (Opd) is generated between the two separated light beams. The instrument is highly stable. Spectral restoration is achieved by the scale, which is precalculated using a laser interferogram. This method suppresses the influence of non-linearity and inherent errors on the restored spectrum. We elaborate on this principle through a theoretical analysis and simulation. Based on a set of design parameters, we successfully restored the spectrum with spectral resolution of 0.25 cm−1 through scale in the case of error (average is –13.88 μm and the mean square deviation is 5.7 μm). The relative spectral mean square error (SMSE) is 0.0013 and the spectral correlation coefficient (SCC) is 0.9997.

Bir Havacılık Elastoplastik Yapısal Delikli Silindirik Bileşenin Döngüsel Mekanik Yük Altında COMSOL Multiphysics ve Taguchi Metodu Optimizasyonu ile Yorulma Analizi

This research study focuses on the fatigue behavior of an aerospace elastoplastic cylindrical structural component with a hole subjected to cyclic mechanical loads. In the demanding operational environment of aerospace applications, the structural components, particularly those with stress concentrators like holes, experience cyclic loading conditions, leading to fatigue failure over time. The key objective of this study is to gain insights into this fatigue behavior, and to develop an optimized set of design and operational parameters that can enhance the fatigue performance of these components. Utilizing the robust finite element analysis capabilities of COMSOL Multiphysics, a comprehensive model of the elastoplastic cylindrical component is developed. The model captures the intricate effects of the hole, a typical stress raiser, on the fatigue performance under various cyclic mechanical loading conditions. A detailed fatigue analysis is then performed using this model, providing valuable insights into the fatigue life and failure patterns of the component. To enhance the fatigue performance, the Taguchi method, a statistical approach, is employed. This method helps to identify and optimize the key design and operational parameters influencing the fatigue life. The parameters are optimized based on their signal-to-noise ratio, with an aim to maximize the fatigue life and ensure the structural integrity of the component under operational cyclic loads. The findings of this research hold significant implications for the design and manufacturing of aerospace structural components, with potential benefits of improved safety, enhanced durability, and reduced maintenance requirements. However, the results' applicability might be limited by the complexity of real-world operational conditions and the assumptions made in the simulation model. Future studies can validate and enhance these results by incorporating more complex loading scenarios and real-world case studies.

Composite anisogrid lattice toroidal shell: Application to a load-carrying rim of the spacecraft reflectarray antenna

A novel design of the composite transformable/foldable rim of the spacecraft reflectarray antenna is presented in the paper. The rim is made in the form of anisogrid lattice toroidal shell split into six parts that are jointed using hinges containing helical springs. The springs create the moments required to deploy the antenna in orbit. A dielectric flexible flat membrane with reflective radiating elements generating a radio signal with required directivity is stretched on the rim. An algorithm of the finite-element model generation is developed for the toroidal rim using a typical finite-element unit cell of lattice structure. The lattice toroidal shell is modelled as a three-dimensional frame composed of curvilinear ribs. The results of design analysis of the lattice rim delivering a minimal mass to its structure subject to constraints imposed on the fundamental frequency, values of stress, and the buckling load factor are presented in this work. The corresponding set of design parameters of lattice structure, including the angle of orientation of helical ribs, number of helical ribs of one orientation, and size of the ribs’ cross section are identified based on these results.

Task scheduling for heterogeneous agents pickup and delivery using recurrent open shop scheduling models

We study the transport-pick agents task scheduling (TPTS) problem in heterogeneous agents pickup and delivery (HAPD). Two functionally heterogeneous agent types, transport agents and pick agents, collaborate to execute multi-goal tasks subjecting to complex-schedule dependency. The objective is to plan a collective time-extended task schedule with the minimization of total completion time. To bridge the gap between robot task scheduling and general scheduling theory, a novel recurrent open shop scheduling (ROSS) problem variant with unique sequence structure is defined. New sequence and schedule models are extended to accommodate for it. Afterwards, the problem-specific append-beam-Christofides (ABC) constructive heuristic, greedy local search (GLS) and simulated annealing (SA) metaheuristic algorithms are designed accordingly. Theoretically, we rigorously analyze sequence and schedule structures, and algorithmic properties; empirically, we study the influence of different algorithm settings on a comprehensive dataset. Design guidelines and parameter settings of these algorithms are provided. The application conditions of the proposed methodology is discussed along with a baseline algorithm TEAMWISE. The proposed methodology could be utilized in various industrial heterogeneous multi-robot or collaborative human–robot systems.

Fast Matrix-Free Methods for Model-Based Personalized Synthetic MR Imaging

Synthetic Magnetic Resonance (MR) imaging predicts images at new design parameter settings from a few observed MR scans. Model-based methods, that use both the physical and statistical properties underlying the MR signal and its acquisition, can predict images at any setting from as few as three scans, allowing it to be used in individualized patient- and anatomy-specific contexts. However, the estimation problem in model-based synthetic MR imaging is ill-posed and so regularization, in the form of correlated Gaussian markov random fields, is imposed on the voxel-wise spin-lattice relaxation time, spin-spin relaxation time and the proton density underlying the MR image. We develop theoretically sound but computationally practical matrix-free estimation methods for synthetic MR imaging. Our evaluations demonstrate superior performance of our methods in currently-used clinical settings when compared to existing model-based and deep learning methods. Moreover, unlike deep learning approaches, our fast methodology can synthesize needed images during patient visits, with good estimation and prediction accuracy and consistency. An added strength of our model-based approach, also developed and illustrated here, is the accurate estimation of standard errors of regional contrasts in the synthesized images. A R package symr implements our methodology. Supplementary materials for this article are available online.

Switching backdrivability of a planetary gear by vibration: design parameter setting and excited force estimation

Switching backdrivability according to use status is important to attain energy-saving and compliance in co-worker robots. Authors have proposed switching backdrivability by exciting gear surface, eliminating the need for sensors while switching. We have confirmed that exciting 2K-H planetary gear can switch its backdrivability. To systematically design the switching backdrivable 2K-H planetary gear, this study reveals less back-drive condition and the required torque for a vibrator. In the less-backdrivable condition, the tooth number difference between the fixed and output gears is dominant. Furthermore, the required torque for the vibrator increases as the load of the output shaft and the vibration frequency increase. The experimental results of the less-backdrivable condition and the required torque for the vibrator are almost entirely consistent with simulation result of the mechanical model

Мathematical model for determining the design parameters of the aerodynamic elements of a deorbit system

The goal of this paper is to develop a mathematical model for choosing the design parameters of deorbit systems’ aerodynamic elements. To solve the problem of near-Earth space debris, it is proposed to deorbit used space objects. Low-Earth orbits are most clogged. Aerodynamic systems are among the most promising systems for space debris removal from low-Earth orbits. They are quite reliable and cheap, but they are sensitive to exposure to space factors. In this paper, aerodynamic systems are decomposed to identify their hierarchic structure, which has the following levels: a subsystem level, an element level, and a parameter level. Materials for the structural components of an aerodynamic element are analyzed. A set of design parameters for aerodynamic systems is formed and used in the development of a mathematical model for choosing the parameters of an aerodynamic element for deorbit systems of various classes: monoblock ones, frame inflatable ones, ones formed by transforming the structure of a space object into an aerodynamic system, and telescopic ones. The material thickness determination model accounts for shell exposure to the space vacuum, atomic oxygen, and excess pressure. It also accounts for errors in determining the ballistic coefficient of an aerodynamic system with a space debris object to be deorbited, the solar activity index, and the atomic oxygen density. The mathematical model for aerodynamic system parameter choice allows one to construct nomograms for determining the parameters of deorbit systems for space debris objects of various classes from their mass and orbit parameters.

ЕКОЛОГІЧНІ ПРИНЦИПИ У ПИТАННЯХ ЗАХИСТУ ТА ЗБЕРЕЖЕННЯ АРХІТЕКТУРНОЇ СПАДЩИНИ

The article examines the actual problem of preservation of architectural heritage on the example of the city of Odesa, and proposes the definition of conditions for their reconstruction and renovation using ecological principles. In addition to determining the value of the monument from the point of view, aesthetic, historical, scientific, its material authenticity, one should not forget the cultural one, which includes social and spiritual values. The problem is that the population of our historical cities is not fully aware of this, not all sections of the population care for the preservation of their architectural heritage, do not actively participate in the processes of reproduction of architectural monuments, preservation of historical buildings, reconstruction, renovation. In order to determine the entire range of issues related to the condition of preservation of historical buildings as part of the sustainable development of the urban environment, such a broad concept as ecological principles should be applied to them. Guided by these principles, it is possible to convey to the population the importance of residents' participation in the restoration and preservation of the historical urban environment. Informing the population about the conditions for preservation and renovation of valuable architectural structures arouses their interest and involvement. A monument that is not used and not integrated into everyday social life ceases to function as a carrier of any social and cultural significance. There is a need to finally determine the environmental principles that can be implemented during reconstruction and restoration, to identify their components to ensure a set of design parameters based on modern international standards and the legislation of Ukraine. Adapting the problems of architectural heritage preservation to the modern needs of citizens, the development of voluntary societies united by heritage preservation programs can be a guarantee of their solution.

Model-based design and multidisciplinary optimization of complex system architectures in the aircraft cabin

The aviation industry is currently facing major challenges due to environmental and socio-economic trends toward sustainable and digitalized aviation. Revolutionary, more powerful and efficient technologies must be rapidly integrated into aircraft, while aircraft manufacturers must demonstrate the required safety. To support the implementation of new concepts, the DLR Institute of System Architectures in Aeronautics is researching methods for end-to-end digitalization from the preliminary design phase to assembly and production. In this context, Model-Based Systems Engineering (MBSE) and Multidisciplinary Design Optimization are important approaches for the development of complex systems. This paper presents a method for the end-to-end use of digital models for multidisciplinary optimization of system architectures. The Systems Modeling Language (SysML) is used to represent the system architecture. The focus is on the cabin and cabin systems, since they are highly coupled to other aircraft systems and have dynamic, customer-specific configuration requirements. The system architecture in SysML is instantiated and configured by the interface to the aircraft fuselage and cabin design parameter sets in the Common Parametric Configuration Schema. The subsequent coupling of the generated system architecture model with the cabin system design model developed in Matlab allows a multidisciplinary optimization of the system properties. A sensitivity analysis is performed using the Passenger Service Unit as an example. The effects of different cabin configurations on the system architecture are investigated and interdisciplinary synergies are identified and analyzed. The results of this analysis are discussed in this paper.

On the Structural Behavior of MEMS Shallow Arch under Combined Effects of In-Plane Parallel Fields and Out-of-Plane Fringing-Fields

We propose to study the nonlinear stroke and lower-order modal interactions of a clamped–clamped shallow-arch flexible micro-electrode. The flexible electrode is electrically actuated through an in-plane parallel-plates field superimposed over out-of-plane electrostatic fringing fields. The in-plane electrostatic fields result from a difference of potential between the initially curved flexible electrode and a lower stationary parallel-grounded electrode. Moreover, the out-of-plane fringing fields are mainly due to the out-of-plane asymmetry of the flexible shallow arch and two respective surrounding stationary side electrodes (left and right). A nonlinear beam model is first introduced, consisting of a nonlinear partial differential equation governing the flexible shallow-arch in-plane deflection. Then, a resultant reduced-order model (ROM) is derived assuming a Galerkin modal decomposition with mode-shapes of a clamped–clamped beam as basis functions. The ROM coupled modal equations are numerically solved to obtain the static deflection. The results indicate the possibility of mono-stable and bi-stable structural behaviors for this particular device, depending on the flexible electrode’s initial rise and the size of its stationary side electrodes. The eigenvalue problem is also derived and examined to estimate the variation of the first three lower natural frequencies of the device when the microbeam is electrostatically actuated. The proposed micro-device is tunable with the possibility of pull-in-free states in addition to modal interactions through linear coupled mode veering and crossover processes. Remarkably, the veering zone between the first and third modes can be electrostatically adjusted and reach 22.6kHz for a particular set of design parameters.

Experimental study on fire spread behavior of single 110 kV cable under different layout conditions

High-voltage cable fire accidents can cause large-scale power outages. In particular, the 110 kV large-section (diameter 10 cm) cable has complex cable structures. Therefore, based on the actual cable laying scenarios, three cable layout conditions are set, including the horizontal cable above horizontal floor structure (HCAHFS), the inclined cable above horizontal floor structure (ICAHFS), and the inclined cable above inclined floor structure (ICAIFS). The combustion behaviors and flame spread characteristics of 110 kV large-section cable are experimentally studied. It is found that the flame cannot spread on the surface of the flame-retardant outer sheath of the cable. However, when the cable-floor distance (lcf) is between 0.75 d and 2 d (d is the cable diameter) in HCAHFS, i.e. there is a floor under the cable that can catch cable melt, and the flame spread characteristics is different. After the cable is ignited, the cable fire can be divided into two parts, outer sheath flame and melt flame, and the cable fire can spread under the joint action of two flames. When lcf ≤ 0.75 d, the space under the cable is narrow. With the accumulation of melt on the floor, air entrainment is limited during cable combustion, resulting in the cable flame unsustainable. When lcf ≥ 2 d, the thermal radiation and convection from the melt and outer sheath flame to the cable preheat zone are weakened, resulting in cable flame extinction as well. In ICAHFS, the cable flame spread rate is first increased and then decreased with the increasing lcf at the fixed inclination angle; In ICAIFS, the upward spread rate of cable flame is faster than the downward spread rate at the fixed inclined angle. Moreover, the cable flame spread rate (FSR) in HCAHFS is the slowest compared to that in ICAIFS with different inclined angles. The preheating length for ICAIFS increases under both upper and lower ignition modes, while it is obviously at upper ignition, due to the melt flow. Finally, a correlation of FSR was proposed for various ignition positions and inclined angles. This study provides a reference for fire protection design and numerical simulation parameter setting of 110 kV cable fire.

A Crafts-based Contemporary Tableware Design Derived from Artisanal Pottery Practice of Penujak Village, Lombok

Craftspeople from various regions of Indonesia have developed specialised earthenware pots and vessels for preparing, cooking, and storing foodstuff. These clay pots and pans’ design is made by adhering to their communal needs, aligned with the local clay’s characteristics. Lombok, an island in Indonesia’s West Nusa Tenggara province known for its pottery, is represented by the three major pottery producing areas of Banyumulek, Masbagik Timur, and Penujak. Primarily, earthenware is chosen for its vast availability and its qualities of porosity allowing for fast firing, cooking over hot woodfire or for cooling and storing. However, distinctive Lombok earthenware pots and vessels have evolved, impacted by local necessities and its clay’s characteristics. Special pre-firing and post-firing techniques have been developed to reduce porosity, smoothen surfaces and produce particular colours. Although these techniques were developed to adjust to the limitations of available resources, they have managed to produce distinctive pottery traits emblematic of the Lombok Potteries. The purpose of this study is to explore the unique qualities of local Lombok earthenware and its potential applications towards creating contemporary tableware designs. Penujak village was chosen as a producing partner for its finer clay and its ability to produce smaller designs. The design process includes these three stages : research on local techniques, setting design parameters, continued with design exploration and experimentation. It is crucial to understand the unique making process of Lombok pottery to utilise its potential in forming the foundations of the contemporary design outputs. Six designs have been produced in this research, deploying distinctive Lombok pottery traits to serve contemporary needs.

A 2 shape slot microstrip patch antenna for global positioning system satellite communication applications

In this paper, a compact two-shape slot microstrip antenna is proposed for global positioning system (GPS) satellite application. The proposed antenna is designed with FR 4 substrate with a height of 1.6 mm, a dielectric constant εr of 4.3 within a compact size 56 x 56 mm2 area. The design parameters are optimized to achieve good performance. At the optimum setting of design parameters, this antenna shows good characteristics to cover L1 band 1,575.42 MHz, ± 12 MHz frequency which is used for GPS satellites. At the 1,572 MHz resonance frequency, this antenna achieves a minimum return loss of -30 dB covering a frequency bandwidth of 50 MHz (1,550 MHz – 1,600 MHz) at -10 dB reference level which ensures 100% bandwidth coverage of the L1 band. Besides, the proposed antenna achieved a maximum gain of 8.3 dBi and a beam width of 1010 at -3 dB point. In terms of other performance, such as voltage standing wave ratio (VSWR), directivity, radiation pattern, the proposed antenna shows good performance for the application of GPS satellites.

Crashworthiness design and optimization of bamboo-inspired tube with gradient multi-cells

This study seeks to understand how bamboo maintains its stability while being lightweight and flexible in strong winds, with the aim of applying the findings to develop an engineering tube that mimics bamboo’s unique structural properties. Initially, image processing revealed convex distribution along the radial direction of the fiber sheath area between bamboo nodes, which was further analyzed to examine its impact on the bending properties of bamboo. Subsequently, a new bionic tube with gradient multi-cells (BTGCs) was introduced, and its crashworthiness was investigated using the Simplified Super Folding Element (SSFE) theory to establish a theoretical model. Additionally, the influence of the structural parameters of BTGCs on its crashworthiness under different loading angles was investigated in silico. The optimal basic design parameters were selected by using the complex proportional evaluation (COPRAS) method, and a Pareto front set of bionic design parameters and impact angles was obtained using artificial neural network (ANN) and non-dominated sorting genetic algorithm (NSGA-II). The results indicated that the optimized BTGCs demonstrated superior crashworthiness compared to conventional circular and bi-layer tubes with an equal mass. This study can serve as a reference for designing highly-efficient bionic tubes.

A Design Approach of a Dedicated Exhaust-Gas Recirculation-System for a Naturally Aspirated Gas Engine—From One-Dimensional Engine Process Simulation and Design of Experiments Up to the Experimental Validation

Abstract This work presents a systematic approach proceeding from the engine process simulation (one-dimensional (1D)-computational fluid dynamics (CFD)) and design of experiments (DoE) up to the experimental validation to build a dedicated exhaust-gas recirculation (EGR) system for a stationary four-cylinder naturally aspirated gas engine. This system should ensure an equal distribution of the recirculated exhaust gas, coming entirely from the rich-operated dedicated cylinder. The rich combustion enables an in-cylinder production of highly reactive species (mainly H2 and CO), resulting in increased EGR reactivity, which improves the dilution tolerance, leading to reduced wall heat losses and lower knock tendency in the EGR receiving cylinders. However, the EGR system design represents a challenge due to the pulsating exhaust gas flow from the dedicated cylinder, which leads to a considerable EGR maldistribution in the receiving cylinders. A numerical analysis of this effect demonstrated that the EGR distribution uniformity depends on the design and dimensions of the EGR path. Considering the numerous design parameters and taking into account that the optimum design of the EGR path is not necessarily the sum of optima from the one-factor-at-a-time variations, efficient DoE methodologies were applied. They enabled identifying the optimum set of the EGR path design-parameters, with an EGR rate maldistribution of about 1% points. To evaluate the quality of the numerical results, the dedicated EGR path with the optimum parameters set was built on the engine test bench. The experimental results confirm the simulative prediction accuracy, demonstrating the reliability of the pursued approach.

Machine learning approaches to determining truck type from bridge loading response

The paper is concerned with the development and comparison of alternative machine learning methods of determining the type of truck crossing a bridge from the dynamic response it induces within the bridge structure, the so-called weigh-in-motion problem. Weigh-in-motion is a rich engineering problem presenting many challenges for current machine learning technologies, and for this reason is proposed as a benchmark for guiding and assessing advances in the application of this field of artificial intelligence. A review is first provided of existing methods of determining truck types and loading attributes using both machine learning and heuristic search techniques. The most promising approach to date, that of artificial neural networks, is then compared to support vector machines in a comprehensive study considering a range of configurations of both modeling techniques. A local scatter point smoothing schema is adopted as a means of selecting an optimal set of design parameters for each model type. Three main model formats are considered: (i) a monolithic model structure with a one-versus-all truck type classification strategy; (ii) an array of sub-models each dedicated to one truck type with a one-versus-all classification strategy; and (iii) an array of sub-models each dedicated to selecting between pairs of trucks in a one-versus-one classification strategy. Overall, the formats that used an array of sub-models performed best at truck classification, with the support vector machines having a slight edge over the artificial neural networks. The paper concludes with some suggestions for extending the work to a broader scope of problems.

SYSTEMATIC CLASSIFICATION OF ADAPTIVE FAÇADES – PREPARING A DATABASE

AbstractAdaptive façades (AF) present a promising approach to reduce environmental impacts in the Architecture, Engineering, and Construction sector. However, the automatization of the façade produces new challenges as the complexity of the system increases. To support the early phase of interdisciplinary development, solution collections such as databases are helpful. Previous research identified that existing solution collections of AF do not meet the requirements that such a method demands. In the effort to develop an optimized database, this paper investigates how the state of the art can be structured in terms of content in order to present it in the database. Here, a set of design parameters is developed based on identified requirements and on the main characteristics of AF that were previously elaborated. This set offers a comprehensive perspective on the previously realized functions and mechanisms of AF and can also contribute to finding creative solutions in the form of new concepts by combining the design parameters in new ways. Finally, 40 case studies of previously implemented adaptive façades are used to evaluate the set of design parameters.

Effects of Coal Permeability Anisotropy on Gas Extraction Performance

To investigate gas flow characteristics in coal seams with strong anisotropy, a coupled anisotropic dual-porosity model was established. Effects of permeability anisotropy on variations in gas pressure, gas extraction volume and effective extraction areas were analyzed. Furthermore, mechanisms of crustal stress, initial gas pressure, ultimate adsorption strain and Langmuir volume constant on permeability anisotropy and extraction amount were studied. Results show that permeability anisotropy could result in an elliptical pressure drop zone around production boreholes. Changes in effective gas extraction areas are divided into three stages: slow growth in an elliptical shape, rapid growth with a superposition effect and steady growth in a funnel shape. Permeability isotropy enables faster reaching of stage III than the anisotropy case. As the vertical stress increases, gas pressure distribution around boreholes gradually changes from an ellipse with horizontal direction as long axis to a circle. Larger initial gas pressure could bring consistently higher gas production in the initial and middle extraction stages, and a faster decrease in the late phase. When gas pressure is 2.5 MPa, the peak daily gas production in initial extraction stage is about three times higher than that in the late phase. Ultimate adsorption strain is positively correlated with permeability change. This relationship becomes more significant with a longer extraction time. In contrast, permeability variation is inversely proportional to the Langmuir volume constant in the initial extraction stage. However, these factors are directly proportional in the late stage. The order of significance of each factor’s effect on permeability is crustal stress > ultimate adsorption strain > initial gas pressure > Langmuir volume constant. Moreover, initial gas pressure has the most significant effect on gas extraction volume, while Langmuir volume constant has the least significant impact. Results could provide a theoretical reference for extraction borehole design and drainage parameter setting to improve extraction performance.