The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform

Yilan Kang - One of the best experts on this subject based on the ideXlab platform.

  • a hypothetical mechanism of bone remodeling and modeling under Electromagnetic Loads
    Biomaterials, 2006
    Co-Authors: Chuanyong Qu, Yilan Kang
    Abstract:

    Abstract A hypothetical regulation mechanism for bone modeling and remodeling under Electromagnetic field is proposed. In this hypothesis, the bone modeling and remodeling mechanism is described as follows: the circular Loads that we bear during ordinary daily activities generate micro-damage in cortical bone and these micro-cracks are removed by osteoclasts. Then growth factors, which are in latent forms in osteocytes, are activated by osteoclasts and released into bone fluid. These growth factors stimulate osteoblasts to refill the cavities. An Electromagnetic field can stimulate the multiplication of growth factors and accelerate the bone remodeling process indirectly. It can be seen that many features reported in adaptive bone modeling and remodeling are explained by the proposed hypothesis. Further, a computational model is established based on the hypothesis, which can simulate the bone modeling and remodeling process under multi-field Loads.

Chuanyong Qu - One of the best experts on this subject based on the ideXlab platform.

  • a theoretical model for surface bone remodeling under Electromagnetic Loads
    Archive of Applied Mechanics, 2008
    Co-Authors: Xiaoqiao He, Chuanyong Qu
    Abstract:

    A theoretical model for surface bone remodeling under Electromagnetic Loads is proposed in this paper. In the model, surface bone remodeling is assumed to be related to growth factors. Growth factors in latent form in osteocytes are released to the bone fluid after the osteocytes are absorbed by osteoclasts, and then regulate the bone formation process. At the same time, environmental loadings can influence the generation of growth factors. This paper shows how surface bone remodeling is triggered under the influence of growth factors. Based on this hypothesis, a computational model is established that simulates the bone coupling remodeling process, including internal and surface bone remodeling. The effects of various loadings, including electrical and magnetic loadings, are simulated and compared. The interactions between internal and surface bone remodeling are investigated via the numerical method. The results indicate that an Electromagnetic field can strongly influence the bone remodeling process and that the remodeling process will be altered after surface bone remodeling is triggered, compared to the sole effect of the internal remodeling process.

  • a hypothetical mechanism of bone remodeling and modeling under Electromagnetic Loads
    Biomaterials, 2006
    Co-Authors: Chuanyong Qu, Yilan Kang
    Abstract:

    Abstract A hypothetical regulation mechanism for bone modeling and remodeling under Electromagnetic field is proposed. In this hypothesis, the bone modeling and remodeling mechanism is described as follows: the circular Loads that we bear during ordinary daily activities generate micro-damage in cortical bone and these micro-cracks are removed by osteoclasts. Then growth factors, which are in latent forms in osteocytes, are activated by osteoclasts and released into bone fluid. These growth factors stimulate osteoblasts to refill the cavities. An Electromagnetic field can stimulate the multiplication of growth factors and accelerate the bone remodeling process indirectly. It can be seen that many features reported in adaptive bone modeling and remodeling are explained by the proposed hypothesis. Further, a computational model is established based on the hypothesis, which can simulate the bone modeling and remodeling process under multi-field Loads.

Youhe Zhou - One of the best experts on this subject based on the ideXlab platform.

  • mechanical behavior of nb3sn strands under transverse Electromagnetic Loads
    Fusion Engineering and Design, 2016
    Co-Authors: Yanyun Ru, Huadong Yong, Youhe Zhou
    Abstract:

    Abstract The performance of Nb 3 Sn cable-in-conduit-conductor (CICC) shows a significant degradation with increasing Electromagnetic load in the International Thermonuclear Experimental Reactor (ITER). As the strand is under the compression caused by adjacent strands, the strand damage may occur for high contact force. In this paper, we present a 3D helix model based on the TEMLOP and FEMCAM to simulate the contact force among the strands under transverse load. The maximum linear strain and indentation depth induced by contact stress are calculated with two-dimensional contact model of cylinder. The numerical results are compared with the experimental values. Finally, the indentation depth is discussed for different layers and cross angles based on two models. With the increasing of layer number, the degradation of performance will occur. The short bending wavelength leads to small indentation depth.

  • contact mechanical characteristics of nb3sn strands under transverse Electromagnetic Loads in the cicc cross section
    Superconductor Science and Technology, 2012
    Co-Authors: Youhe Zhou, Xiaojing Zheng
    Abstract:

    This paper presents a new code for the two-dimensional discrete element method (DEM) and relevant simulations to quantitatively characterize the contact force behavior of the Nb3Sn strands in the ITER CICC cross-section under a transverse Electromagnetic load. In order to obtain the essential parameters in the contact force model employed in the DEM, a simulation of the experiments conducted by Nijhuis et al (2004 IEEE Trans. Appl. Supercond. 14 1489–94) is first performed, where the load–displacement curve predicted by the code is in good agreement with the measurements. After that, the contact force chain between strands and its distribution is quantitatively analyzed by the code. It is found that the contact force distribution among strands is heterogeneous and strongly anisotropic. In other words, the force chain distribution, which determines the behavior of the assembly of strands with discrete media, and the distribution of area average magnitude of the contact force are obviously inhomogeneous. To describe this inhomogeneity, here, the probability density function (PDF) is used in the statistical analysis. The numerical results show that the PDFs of the magnitudes of the resultant contact force, normal contact force, and tangential contact force all decay with an exponential law, and that PDFs of the directions of the contact forces are all anisotropic and exhibit about six periodic changes in which the peak values in the direction parallel to the applied Electromagnetic load are appreciably larger than the other peaks.

Xiaojing Zheng - One of the best experts on this subject based on the ideXlab platform.

  • contact mechanical characteristics of nb3sn strands under transverse Electromagnetic Loads in the cicc cross section
    Superconductor Science and Technology, 2012
    Co-Authors: Youhe Zhou, Xiaojing Zheng
    Abstract:

    This paper presents a new code for the two-dimensional discrete element method (DEM) and relevant simulations to quantitatively characterize the contact force behavior of the Nb3Sn strands in the ITER CICC cross-section under a transverse Electromagnetic load. In order to obtain the essential parameters in the contact force model employed in the DEM, a simulation of the experiments conducted by Nijhuis et al (2004 IEEE Trans. Appl. Supercond. 14 1489–94) is first performed, where the load–displacement curve predicted by the code is in good agreement with the measurements. After that, the contact force chain between strands and its distribution is quantitatively analyzed by the code. It is found that the contact force distribution among strands is heterogeneous and strongly anisotropic. In other words, the force chain distribution, which determines the behavior of the assembly of strands with discrete media, and the distribution of area average magnitude of the contact force are obviously inhomogeneous. To describe this inhomogeneity, here, the probability density function (PDF) is used in the statistical analysis. The numerical results show that the PDFs of the magnitudes of the resultant contact force, normal contact force, and tangential contact force all decay with an exponential law, and that PDFs of the directions of the contact forces are all anisotropic and exhibit about six periodic changes in which the peak values in the direction parallel to the applied Electromagnetic load are appreciably larger than the other peaks.

Olesya I. Zhupanska - One of the best experts on this subject based on the ideXlab platform.

  • Influence of the electric current waveform on the dynamic response of the electrified composites
    International Journal of Mechanics and Materials in Design, 2013
    Co-Authors: A. Barakati, Olesya I. Zhupanska
    Abstract:

    The influence of the electric current waveform (DC, AC and pulsed currents) on the dynamic Electromagnetic, thermal, and impact response of the composite plate is studied. The analysis includes solving Maxwell’s equations in the electrified composite plate to determine an electric-current induced magnetic field and heat transfer equation to estimate the electric-current-induced heating. In addition, the dynamic mechanical response of the electrified composite plate subjected to impact and various Electromagnetic Loads (DC, AC, pulsed electric currents and a constant magnetic field) is analyzed by solving a coupled system of equations of motion and Maxwell’s equations in the composite plate. The results show that the dynamic response of the plate is highly dependent on the characteristics of the Electromagnetic field, and the pulsed Electromagnetic fields are most effective in reducing vibrations caused by the application of dynamic mechanical Loads.

  • Thermal and Mechanical Response of a Carbon Fiber Reinforced Composite to a Transverse Impact and In-Plane Pulsed Electromagnetic Loads
    Journal of Engineering Materials and Technology-transactions of The Asme, 2012
    Co-Authors: A. Barakati, Olesya I. Zhupanska
    Abstract:

    Thermal and mechanical response of a carbon fiber polymer matrix composite plate subjected to a transverse impact and in-plane pulsed Electromagnetic Loads is studied. Heat transfer analysis in the electrified composite plate for the electric currents of various waveforms (direct current (DC), alternating current (AC), and pulsed) is conducted, and the effects of the waveform parameters (characteristic time, peak, etc.) on the current-induced heating in the composite are investigated. The results show that pulsed electric currents cause significant temperature rises only in the regions immediately adjacent to the electric contact (composite-electrode interface). As for the mechanical response of the composite plate, it is found that the characteristics of the Electromagnetic field (waveform, duration of application, and intensity) can significantly reduce deflection and stresses in the plate, and concurrent application of a pulsed Electromagnetic load can effectively mitigate the effects of the impact load in the electrically conductive composites.

  • Effects of Coupled Fields on the Mechanical Response of Electrically Conductive Composites
    Procedia Engineering, 2011
    Co-Authors: A. Barakati, Olesya I. Zhupanska
    Abstract:

    Abstract In this work, the possibility for improvement of impact resistance of electric-current-carrying composite structures in the presence of an Electromagnetic field is investigated. Governing equations describing the electro-magneto-mechanical interactions in anisotropic materials and the corresponding two-dimensional approximation for transversely isotropic plates are discussed. An efficient numerical procedure is developed to solve the resulting nonlinear boundary value problem for a long transversely isotropic current-carrying plate subjected to impact and pulsed Electromagnetic Loads. The numerical results show that the dynamic response of the plate highly depends on the magnitude and direction of the Electromagnetic Loads.