Papers by Keyword: Coupling Model

Abstract: The coupled model is presented to describe the elements penetration into the surface layer of metal during the process of ion implantation. Mechanical stresses arising due to the interaction of particles with the surface affect the redistribution of the implanted impurity. In addition, the existence of vacancies in the metal surface and their generation under the stresses influence are taken into account. The kinetic law is written on the basis of the thermodynamics of irreversible processes. The solution had been found numerically. As a result, the distributions of impurity concentration and deformations have been obtained for various time moments. The comparison of the concentration profiles with vacancies and without their have been given.

Abstract: Based on the existing fiber reinforced polymer (FRP) durability research, considering the difference different regions, a multi-factor durability evaluation model for structural reinforcement FRP has been established. Firstly, combined with the result of rapid aging experiments, a benchmark aging model of a single factor is built. Secondly, classifying the various factors according to different geographical environments, and taking the difference between various environmental factors and test conditions into count, the benchmark aging model is revised. Thirdly, it is to make sure the main environmental factors, determine the effect weight of various factors in different areas and a coupling aging model is established through the coupled superposed. Finally, the carbon fiber reinforced polymer (CFRP) coupling aging model is obtained and compared with actual environmental in A area as an example to validate the model. The result that it can ascertain both trends are consistent and be used to guide durable design.

Abstract: Suspension and steering systems are the two important subsystems of the vehicle chassis, and the two are not independent of each other, but are closely linked, so the coupling relationships between the two need to be considered to make the integrated control. Based on the tire force, dynamic load distribution, coupling movement relations, and coupling its structure and control parameters, a dynamic model of tire and suspension control system for is built to provide a model basis and research base for the study of the vehicle chassis system control.

Abstract: Zhushan Bay watershed to the northwest of Lake Taihu was selected as the research area. Taking the close connection of water quality and quantity of river-lake system into consideration, we constructed a water environmental coupling model of 1-D river network and 2-D lake to simulate hydrodynamic and water quality of river-lake system. Based on the results of field measured data, the constructed model was calibrated and validated. According to results of calibration, the range of river roughness was 0.02~0.028, the degradation coefficient of COD, NH₃-N and TP degradation coefficient was 0.09~0.11 d^-1, 0.05~0.07 d^-1 and 0.04 d^-1, respectively; the lake bottom roughness was 0.025, the wind stress coefficient was 0.0013, the degradation coefficient of COD, NH₃-N and TP degradation coefficient was 0.06、0.04 and 0.02 d^-1, respectively. The calculated results fit well with the experimental results, indicating that the model has good practicality.

Abstract: There exists complicated relationship among energy, economy and environment. Every single system contains a lot of uncertain information and indexes of one system may affect other systems. So, this paper views energy,economy,environment as a system and analyzes the coupling relatiopnship by establishing a coupling model of energy-economy-environment system according to the system coupling theory. The paper selects Beijing City as the research target and applies the model with the index data of energy-economy-environment system from 2004 to 2011. The results show that the model can reflect the changing trend of every two subsystems’ interaction relationship, which will help to explore the essential relationship and predict the development of the system.

Abstract: As one of Best Management Practices, Vegetative Filter Strip (VFS) had been widely application and their effects were fine. Planning and design VFS is based on quantitative predicting the purification effect. A mathematical model by coupling Vegetative Filter Strip Model (VFSMOD) with the Modified Universal Soil Loss Equation (MUSLE) was designed to estimate sediments trapping efficiency of VFS under the different conditions. Furthermore, in this paper the applicability of coupling model had been tested well by plot experiments in Chinese northwest, so the coupling model was applied to simulate the efficacy of VFS in Shaanxi Heihe River basin. Result reveals that grassed filter strips with about 10 m width are reasonable in Heihe River basin. Besides that, it is unsuitable to set grassed filter strips under the conditions of 15° above slope in river bank.

Abstract: After mining, a dynamic distribution of mining fissure elliptic paraboloid zone in the overlying stratum would be formed. Based on the rock mechanics, seepage flow mechanics, mass transfer theory and elastic-plastic theory, the coal-rock mass deformation equation, mixture gas seepage equation and gas diffusion equation of the mining fissure elliptic paraboloid zone are deduced. Combined with various boundaries, initial conditions, the multi-field coupling mathematical model of mining fissure elliptic paraboloid is obtained. The model provides a theoretical basis for numerical simulation of gas drainage system layout.

Abstract: Aiming at solving the existing problems of gas treatments on the upper corner presently,poor drainage effect and the high cost of engineering quantity included , gas drag pipe drainage technology and processes on the upper corner is designed.It can make the drainage point matching working face advance speed, realize continuous drainage points in space.And research on the drainage parameters is the foundation of the successful implementation of drag drainage pipe technology.It introduced Brinkman equation, Fick's law of diffusion and gas diffusion translational equations to describe the behavior of gas flow diffusion ,established the migration and diffusion gas flow model at working face ,and the two models are combined in a unified flow field., establishing a coupling model of multi-physics gas flow at the working face.And the model is solved by fluent to determine the optimal parameters of towing pipe drainage.Finally,it makes a practical application and testing results in Changcun coal mine working face N3-8. The results show that gas drag pipe drainage technology is conducing to governing on the accumulation of corner gas,and the gas concentration on the upper corner down to 1%,determining the best the drainage location for distance back plane 2.4m, an inclined direction distance back to the wind tunnel 1.6m, along strike depth to goaf 15m .Taking measures to block the upper corner,which can improve the drainage concentration,and make the concentration of gas on the upper corner down to 0.6%.The application of field basically agrees with the simulation results,so pipe drainage technology has feasibility and good applicability of top corner gas drag

Abstract: Distribution of magnetic flux density and magnetic force in electromagnetic riveting was investigated with the electromagnetic field coupling model established by the finite element method. The results show the radial magnetic flux density presents a sinusoidal exponential decaying form at a point and the maximum value of radial magnetic flux density lies in about half of the driver plate radius along the driver plate radius direction. The distribution of magnetic force is determined by that of magnetic flux density and the magnetic force is a body force, which weakens very quickly from the inside to the outside of the driver plate. In order to prevent penetration of magnetic field, the thickness of driver plate is an important parameter to increase the energy utilization ratio.

Abstract: Considering the reservoir seepage, borehole wall inflow, fracture and perforation flow’s process and mutual influence, an unsteady state computation model of fractured horizontal well coupling with reservoir was established based on the source function and superposition principle. Calculation results showed that compared to the production only from the hydraulic fractures, the difference of that both from fractures and perforations was great early and decreased slowly later. Take the perforation production for example, because of mutual interference and well bore flow friction, different location perforations with different output and the central-perforation production was lower than that of the outer-position.