Search for: 3d-modeling
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    Three-dimensional scattering of plane harmonic SH, SV, and P waves in multilayered alluvial valleys

    , Article Asian Journal of Civil Engineering ; Volume 11, Issue 5 , 2010 , Pages 605-626 ; 15630854 (ISSN) Omidvar, B ; Rahimian, M ; Mohammadnejad, T ; Sanaeiha, A ; Sharif University of Technology
    In this paper, three-dimensional amplification of plane harmonic SH, SV, and P waves in multilayered alluvial valleys is investigated by using a boundary element method in frequency domain. It is shown that in order to achieve real responses, the problem must be analyzed and modeled three-dimensionally. Also, for exact evaluation of surface ground motions in alluvial valleys all key parameters such as layering, material and geometrical characteristics of each layer, stimulation frequency, wave type, plus angle and azimuth of incidence must be taken into account altogether. The accuracy and efficiency of the proposed formulations for the computation of the surface displacement field... 

    3D numerical simulation of elasto-plastic behaviour in powder compaction process using a quasi-nonlinear technique

    , Article Journal of Materials Processing Technology ; Volume 143-144, Issue 1 , 2003 , Pages 886-890 ; 09240136 (ISSN) Khoei, A. R ; Iranfar, S ; Sharif University of Technology
    In this paper, the 3D analysis of metal powder during the cold compaction process is simulated by the finite element method based on deformation theories. Since the compaction process involves a very large reduction in volume, a large displacement finite element method is applied for the spatial discretization. During compaction, powders exhibit strain or work hardening, the volume reduces and the material becomes harder. In this study, a quasi-nonlinear analysis is carried out during the FE modelling of powder forming process. The material parameters are experimentally established as functions of relative density. These nonlinear functions are incorporated into the inelastic analysis of... 

    New seepage-related design graphs for rock-fill dams

    , Article International Symposium on Dams in the Societies of the 21st Century, ICOLD-SPANCOLD - Dams and Reservoirs, Societies and Environment in the 21st Century, Barcelona, 18 June 2006 through 18 June 2006 ; Volume 1 , 2006 , Pages 971-978 ; 0415404231 (ISBN); 9780415404235 (ISBN) Soleimanbeigi, A ; Jafarzadeh, F ; Sharif University of Technology
    Taylor and Francis/ Balkema  2006
    Seepage analysis serves as one of the most significant stages in the design process of an embankment dam. In two-dimensional (2D) seepage analysis of embankment dams, little or no attention is paid to the widthwise flows from side abutments. Moreover, the role of grout curtain extensions into the side abutments and abutment material properties are inevitably neglected when performing seepage analyses in 2D plane. In this paper, two and three-dimensional (3D) models of a rock-fill dam are generated and several unsteady and steady state seepage analyses are performed using finite element method (FEM). The results obtained from 2D and 3D seepage analyses were compared with measurements from the... 

    SM3D studio: A 3D model constructor

    , Article Iranian Conference on Machine Vision and Image Processing, MVIP ; 2013 , Pages 10-15 ; 21666776 (ISSN); 9781467361842 (ISBN) Soleimani, V ; Vincheh, F. H ; Zare, E ; Engineers (IEEE) Antennas and Propagation Society; The Institute of Electrical and Electronics ; Sharif University of Technology
    IEEE Computer Society  2013
    In this paper we describe designing and implementation of a powerful, fast and compact simple 3D modeler (SM3D). In addition to saving cost and time (due to high processing speed), 3D objects can be created with minimum system resources by using this application. Easy learning and using are other strengths of this application. Modularity using classification and applying Dynamic-Link Library files are noted aspects that are regarded in writing the source code and this causes separation of main part and user interface, so the application can be easily expanded in the future. Ability to create primary objects and also applying advanced transformations and modifiers have been considered.... 

    3D modeling of a superconducting transition edge detector

    , Article 29th Iranian Conference on Electrical Engineering, ICEE 2021, 18 May 2021 through 20 May 2021 ; 2021 , Pages 56-60 ; 9781665433655 (ISBN) Ansari, S ; Nazifi, R ; Yaghoubi Arzefouni, M ; Mohajeri, R ; Mirzaei, I ; Fardmanesh, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Improving the sensitivity and the time response of the superconducting transition edge detectors as one of the most promising technologies for millimeter and sub-millimeter wavelength radiation power detection is essential. Having an accurate 3D model for these detectors enables us to design faster detectors with higher sensitivity and detectivity. In this paper, we report on a 3-dimensional finite element model of a current biased superconducting YBa2Cu3O7-x (YBCO) transition-edge detector fabricated by a low-cost Metal-Organic deposition method. The obtained simulation results are in good agreement with the measured response of the detectors. Also, as the simulation results suggest,... 

    Assessment and comparison of different arrangements of horizontal ground heat exchangers for high energy required applications

    , Article Applied Thermal Engineering ; Volume 167 , 2020 Asgari, B ; Habibi, M ; Hakkaki Fard, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Horizontal ground heat exchangers (GHEs) have a lower initial installation cost in comparison to vertical ones; however, they require more land area. In order to reduce the required land area of horizontal GHEs, their heat exchange rate per unit land area needs to be enhanced. A remedy to this problem is installing horizontal GHEs in an arrangement with maximum heat exchange rate per unit land area. However, such arrangements have not been introduced for different types of horizontal GHEs thus far. To this end, in this study, the thermal performance of various GHE pipe arrangements for three different types (linear, spiral, and slinky) of horizontal GHEs is evaluated. Comparing the obtained... 

    Development of physical 3D model of maternal-fetal to study light interaction through tissue

    , Article 2012 International Conference on Biomedical Engineering, ICoBE 2012 ; 2012 , Pages 557-561 ; 9781457719899 (ISBN) Jumadi, N. A ; Gan, K. B ; Mohd Ali, M. A ; Zahedi, E ; Sharif University of Technology
    The development of a synthetic model of a pregnant woman abdomen with amniotic fluid and a fetus is discussed comprehensively in this paper. The model is intended to be used for studying the light propagation through physical 3D model of pregnant woman in reflectance mode. To construct the model, reported dimension values of body curvature in 26 and 28 weeks of pregnant woman are being used as main references. Although slightly adjustments have been made to the body dimensions, the values are still within the range of reference values. Optical simulation has been performed in order to test the model capability. Given the reasonable computational time and encouraging preliminary results, the... 

    The determination of meshing force distribution for spur gears

    , Article 2008 ASME International Mechanical Engineering Congress and Exposition, IMECE 2008, Boston, MA, 31 October 2008 through 6 November 2008 ; Volume 11 , 2009 , Pages 451-458 ; 9780791848722 (ISBN) Durali, M ; Ghasabzadeh Saryazdi, M ; Sharif University of Technology
    This article presents a method for determination of meshing force distribution on contact region of spur gear teeth. In this method it is assumed that there are inter-connected springs on the teeth profile. These springs treat as capacitive fields. The compliance matrices of these fields are determined from the results of finite element analysis done on 3-D model of a gear. The tooth compliance matrix is used as a reference data to determine the tooth deformations for any meshing situation. The meshing force distribution is calculated using this reference data and Hertz theory for contacting bodies. The results of this analysis help in stress analysis under real operation conditions and more... 

    Modeling the R-curve effects in laminate composites using the interface thick level set method

    , Article Theoretical and Applied Fracture Mechanics ; Volume 108 , August , 2020 Latifi, M ; Kouchakzadeh, M. A ; Sharif University of Technology
    Elsevier B. V  2020
    This paper presents a new model for simulating delamination growth in composites in presence of the resistance curve (R-curve) effects. This model is extended from the interface thick level set (ITLS) method which is developed recently. In this approach the common definition of damage in the constitutive relationship of the interface elements is replaced with a new damage definition based on the thick level set (TLS) method. This new damage definition provides a direct link between fracture and damage mechanics that allows use of interface elements without a predefined cohesive law. In this paper the ITLS method is adopted to incorporate the R-curve effects caused by extended bridging, in... 

    3D modeling of large elasto-plastic deformation via the extended finite element method

    , Article 9th International Conference on Computational Plasticity: Fundamentals and Applications, COMPLAS IX, Barcelona, 5 September 2007 through 7 September 2007 ; Issue PART 2 , 2007 , Pages 894-897 ; 9788496736290 (ISBN) Khoei, A. R ; Biabanaki, S. O. R ; Anahid, M ; Sharif University of Technology
    In this paper, the extended finite element method is presented for large elasto-plastic deformation in 3D solid mechanics problems. The X-FEM computational algorithm is presented in the framework of Lagrangian description in order to model the arbitrary discontinuities in large deformations. The discontinuity between two bodies is modeled by using the X-FEM technique and applying a modified level set enrichment function. In order to simulate the nonlinear behavior of materials, the Lagrangian plasticity formulation is coupled with the X-FEM technique. Finally, numerical example is analyzed to demonstrate the efficiency of the X-FEM technique in large plasticity deformations. © CIMNE 2007  

    Error propagation in non-iterative EIT block method

    , Article ISSPIT 2007 - 2007 IEEE International Symposium on Signal Processing and Information Technology, Cairo, 15 December 2007 through 18 December 2007 ; 2007 , Pages 678-681 ; 9781424418350 (ISBN) Abbasi, A ; Pashakhanlou, F ; Vosoughi Vahdat, B ; Sharif University of Technology
    The Block method approach to solve EIT problem leads to an exact solution if the measurements are done without error. Non-iterative method is a feasible approach on solving 3D EIT forward problem. However, the effect of the measurement error has not been considered in this method yet. In this article, the 3D model of EIT with block method has been considered. The required equations to solve the forward problem are then generated. To solve the forward problem, non-iterative method has been employed. Effect of the measurement error on forward problem for a 3D model of EIT are generated. It has been shown that for a sample 3D model, measurement error can propagate exponentially. ©2007 IEEE  

    A model for inhomogeneous large deformation of photo-thermal sensitive hydrogels

    , Article Acta Mechanica ; Volume 232, Issue 8 , 2021 , Pages 2955-2972 ; 00015970 (ISSN) Mazaheri, H ; Namdar, A. H ; Ghasemkhani, A ; Sharif University of Technology
    Springer  2021
    The current study develops a 3D constitutive model for photo-thermal sensitive hydrogels based on free energy decomposition. The hydrogel under study is PNIPAM network with copper chlorophyllin nanoparticle agents attached to the network. The effect of light intensity is considered as a rise in temperature since chlorophyllin nanoparticle agents absorb light irradiation and convert it to heat. Moreover, it is necessary to consider the effect of dissociation of these agents on the hydrogel’s free energy function; therefore, a term is added to the free energy function. After introducing the model, some problems, including the free swelling and uniaxial loading problems, are studied, and the... 

    3D distributed modeling of trolling-mode AFM during 2D manipulation of a spherical cell

    , Article Journal of Nanoparticle Research ; Volume 23, Issue 4 , 2021 ; 13880764 (ISSN) Mohammadi, S.Z ; Nejat Pishkenari, H ; Mohammadi Moghaddam, M ; Sharif University of Technology
    Springer Science and Business Media B.V  2021
    In this study, a general 3D distributed modeling of Trolling-Mode AFM (TR-AFM) as a nanorobot is presented to analyze the 2D manipulation process of a spherical cell. To this aim, the analysis is categorized into 3 sections. In the first section, 6 deformations of TR-AFM are taken into account, and the standard model of the system is obtained. Moreover, the system is simulated in ANSYS Workbench. The results of modal and transient analyses of the system from both analytical and software methods reveal high agreement, which confirms the accuracy of the presented analytical model. In the second section, by utilizing the 3D derived model, displacement of a spherical yeast single cell (W303)... 

    Assessment of 2DH and pseudo-3D modelling platforms in a large saline aquatic system: Lake Urmia, Iran

    , Article Hydrological Processes ; Vol. 28, Issue. 18 , 2014 , pp. 49534970 ; ISSN: 10991085 Zeinoddini, M ; Tofighi, M. A ; Bakhtiari, A ; Sharif University of Technology
    The main objective of this paper is to provide comparative quantitative examinations on the capabilities of two-dimensional horizontal and pseudo-three-dimensional (3D) modelling approaches for simulating spatial and temporal variability of the flow and salinity in Lake Urmia, Iran. The water quality in the lake has been an environmentally important subject partly because this shallow hypersaline aquatic ecosystem is considered to be one of the largest natural habitats of a unique multicellular organism, Artemia urmiana. This brine shrimp is the major food source for many of the protected and rare shorebirds that visit the lake. A.urmiana can grow and survive in certain ranges of salinity,... 

    An analytical 3-D model for calculating eddy-current damping force for a magnetic levitation system with permanent magnet

    , Article IEEE Transactions on Magnetics ; Volume 48, Issue 9 , Sept , 2012 , Pages 2472-2478 ; 00189464 (ISSN) Ebrahimian, M ; Khodabakhsh, M ; Vossoughi, G ; Sharif University of Technology
    IEEE  2012
    An analytical solution for obtaining steady-state eddy-current-based force on a levitated permanent magnet above a plate with linear conductivity in the field of an electromagnet having cylindrical symmetry is presented in this paper. In literature, the force due to eddy current in this levitation system have been used for high precision positioning of a levitated permanent magnet without providing an explicit analytical model. In this system, a change in the coil's current and also the motion of the levitated permanent magnet in 3-D space generate eddy current in the plate. A novel explicit solution for obtaining damping forces due to these eddy currents is obtained as a function of... 

    Linear and nonlinear model of cutting forces in peripheral milling: A comparison between the accuracy of 2D and 3D models

    , Article 2009 ASME International Mechanical Engineering Congress and Exposition, IMECE2009, Lake Buena Vista, FL, 13 November 2009 through 19 November 2009 ; Volume 3 , 2010 , Pages 955-962 ; 9780791843765 (ISBN) Moradi, H ; Movahhedy, M. R ; Vossoughi, G ; Sharif University of Technology
    Peripheral milling is extensively used in manufacturing processes, especially in aerospace industry where end mills are used for milling of wing parts and engine components. Knowledge of the cutting forces is the first necessary stage in analysis of the milling process. In this paper, cutting forces are presented for both two and three dimensional models. Instead of the common linear dependency of cutting forces to the cut chip thickness, two nonlinear models are presented. In the first model, cutting forces are considered as a function of chip thickness with a complete third order polynomial. In the second one, the quadratic and constant terms of the third order polynomial are set to zero.... 

    Fracture characterizing and modeling of a porous fractured carbonate reservoir

    , Article Society of Petroleum Engineers - SPE/EAGE Reservoir Characterization and Simulation Conference 2009 - Overcoming Modeling Challenges to Optimize Recovery, 19 October 2009 through 21 October 2009 ; Volume 1 , 2009 , Pages 303-319 ; 9781615677443 (ISBN) Dashti, R ; Bagheri, M. B ; Ulhaq, S ; Sharif University of Technology
    Anisotropy and heterogeneity in reservoir properties introduce challenges during the development of hydrocarbon reservoirs in naturally fractured reservoirs. In reservoir simulations, grid-block properties are frequently assigned to obtain reasonable history matches. Even then, accuracy with regard to some aspects of the performance such as water or gas cuts, breakthrough times, and sweep efficiencies may be inadequate. In some cases, this could be caused by the presence of substantial flow through natural fractures. In this work the fracture characterization and modeling was performed in a highly fractured carbonate reservoir in SW Iran. It was observed that reservoir simulation based on... 

    AM3D: An accurate crosstalk probability modeling to predict channel delay in 3D ICs

    , Article Microelectronics Reliability ; Volume 102 , 2019 ; 00262714 (ISSN) Shirmohammadi, Z ; Nikoofard, A ; Ershadi, G ; Sharif University of Technology
    Elsevier Ltd  2019
    Migration from Two Dimensional Integrated Circuits (2D ICs) to Three Dimensional Integrated Circuits (3D ICs) reduces the delay due to the shorter wire length between sender and receiver. However, Through-Silicon-Vias (TSVs) that connect layers in the structure of 3D ICs can seriously increase the delay due to capacitance coupling between TSVs and lead to crosstalk fault. The severity of crosstalk faults depends on transitions appearing on TSVs that is called transition patterns. To propose an efficient crosstalk tackling mechanisms in 3D ICs, an accurate probability analytical model is required to predict the delay caused by TSVs (3D ICs) in the attendance of these transition patterns. In... 

    Effects of rigid bus conductors on seismic fragility of electrical substation equipment

    , Article Soil Dynamics and Earthquake Engineering ; Volume 125 , 2019 ; 02677261 (ISSN) Baghmisheh, A. G ; Estekanchi, H. E ; Sharif University of Technology
    Elsevier Ltd  2019
    The present paper studies the impact of dynamic interaction between high-voltage substation equipment on the response and vulnerability of substation equipment. The 3D numerical model is developed for four types of vulnerable equipment in the both unconnected and connected conditions. The bus slider-rigid bus assembly is utilized to establish the connection between the equipment. The incremental dynamic analysis is carried out in the developed systems to produce the fragility function for each equipment. Also, the Monte Carlo approach is employed to evaluate the accuracy of the generated functions. It is concluded that the incorporation of connection parts in the model can significantly... 

    Seismic performance evaluation of a novel bolted flush end-plate beam splice connection

    , Article Proceedings of the Institution of Civil Engineers: Structures and Buildings ; Volume 173, Issue 2 , 2020 , Pages 109-127 Keikha, H ; Mofid, M ; Sharif University of Technology
    ICE Publishing  2020
    This paper describes a three-dimensional (3D) finite-element (FE) model developed to assess the seismic behaviour of a novel prefabricated beam-to-beam connection termed a double-bolted flush end-plate beam (DBFEB) splice connection under cyclic loading. The seismic response was analysed and evaluated in terms of the hysteretic behaviour, rigidity, resistance degradation, ductility, energy dissipation capacity and equivalent damping coefficient. It is shown that the required performance can be achieved by controlling the end-plate thickness as well as the bolt grade and diameter; these parameters were therefore chosen as the key geometric variables investigated here for parametric study....