• Title/Summary/Keyword: ANSYS

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ANSYS Simulation of VHF Ceramic Resonator Using Thickness-longitudinal vibration mode (두께 진동모드를 이용한 고주파 세라믹 Resonator의 ANSYS Simulation)

  • 홍재일;윤현상;민석규;윤광희;류주현;김종선;박창엽
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.259-262
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    • 2000
  • In this study, 3.1$\times$3.7$\times$0.365 $\textrm{mm}^2$ model of thickness-longitudinal vibration mode VHF ceramic resonator with (Pb,Ca)(Co,W,Ti)O$_3$ ceramics was simulated by ANSYS according to the electrode size. With the variations of electrode size of the model, fundamental and the third overtone dynamic ratio was investigated. At the ratio of electrode to model thickness(1/t) 2.5, third overtone dynamic ratio was largely increased. That model is suitable for 20 MHz resonator.

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Flutter analysis of long-span bridges using ANSYS

  • Hua, X.G.;Chen, Z.Q.;Ni, Y.Q.;Ko, J.M.
    • Wind and Structures
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    • v.10 no.1
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    • pp.61-82
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    • 2007
  • This paper presents a novel finite element (FE) model for analyzing coupled flutter of long-span bridges using the commercial FE package ANSYS. This model utilizes a specific user-defined element Matrix27 in ANSYS to model the aeroelastic forces acting on the bridge, wherein the stiffness and damping matrices are expressed in terms of the reduced wind velocity and flutter derivatives. Making use of this FE model, damped complex eigenvalue analysis is carried out to determine the complex eigenvalues, of which the real part is the logarithm decay rate and the imaginary part is the damped vibration frequency. The condition for onset of flutter instability becomes that, at a certain wind velocity, the structural system incorporating fictitious Matrix27 elements has a complex eigenvalue with zero or near-zero real part, with the imaginary part of this eigenvalue being the flutter frequency. Case studies are provided to validate the developed procedure as well as to demonstrate the flutter analysis of cable-supported bridges using ANSYS. The proposed method enables the bridge designers and engineering practitioners to analyze flutter instability by using the commercial FE package ANSYS.

Numerical Investigation of Sunroof Buffeting for Hyundai Simplified Model (HSM의 썬루프 버페팅 수치해석)

  • Khondge, Ashok;Lee, Myunghoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.3
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    • pp.180-188
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    • 2014
  • Hyundai Motor Group(HMG) carried out experimental investigation of sunroof buffeting phenomena on a simplified car model called Hyundai simplified model(HSM). HMG invited participation from commercial CFD vendors to perform numerical investigation of sunroof buffeting for HSM model with a goal to determine whether CFD can predict sunroof buffeting behavior to sufficient accuracy. ANSYS Korea participated in this investigation and performed numerical simulations of sunroof buffeting for HSM using ANSYS fluent, the general purpose CFD code. First, a flow field validation is performed using closed sunroof HSM model for 60 km/h wind speed. The velocity profiles at three locations on the top surface of HSM model are predicted and compared with experimental measurement. Then, numerical simulations for buffeting are performed over range of wind speeds, using advanced scale resolving turbulence model in the form of detached eddy simulation (DES). Buffeting frequency and buffeting level are predicted in simulation and compared with experimental measurement. With reference to comparison between experimental measurements with CFD predictions of buffeting frequency and level, conclusion are drawn about predictive capabilities of CFD for real vehicle development.

On the FE Modeling of FRP-Retrofitted Beam-Column Subassemblies

  • Ronagh, H.R.;Baji, H.
    • International Journal of Concrete Structures and Materials
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    • v.8 no.2
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    • pp.141-155
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    • 2014
  • The use of fiber reinforced polymer (FRP) composites in strengthening reinforced concrete beam-column subassemblies has been scrutinised both experimentally and numerically in recent years. While a multitude of numerical models are available, and many match the experimental results reasonably well, there are not many studies that have looked at the efficiency of different finite elements in a comparative way in order to clearly identify the best practice when it comes to modelling FRP for strengthening. The present study aims at investigating this within the context of FRP retrofitted reinforced concrete beam-column subassemblies. Two programs are used side by side; ANSYS and VecTor2. Results of the finite element modeling using these two programs are compared with a recent experimental study. Different failure and yield criteria along with different element types are implemented and a useful technique, which can reduce the number of elements considerably, is successfully employed for modeling planar structures subjected to in-plane loading in ANSYS. Comparison of the results shows that there is good agreement between ANSYS and VecTor2 results in monotonic loading. However, unlike VecTor2 program, implicit version of ANSYS program is not able to properly model the cyclic behavior of the modeled subassemblies. The paper will be useful to those who wish to study FRP strengthening applications numerically as it provides an insight into the choice of the elements and the methods of modeling to achieve desired accuracy and numerical stability, a matter not so clearly explored in the past in any of the published literature.

A Study on the Optimal Design of Laminate for CNG composite vessel using ANSYS RSM (ANSYS RSM을 이용한 CNG차량 용기 필라멘트 와인딩 적층판 최적설계에 관한 연구)

  • Kim, Eui-Soo
    • Journal of the Korean Institute of Gas
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    • v.13 no.4
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    • pp.15-21
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    • 2009
  • The fiber reinforced composite material is widely used in the multi-industrial field where the weight reduction of the infrastructure is demanded because of their high specific modulus and specific strength. Pressure vessels using this composite material have two main merits which are to cut down energy by reducing weight and to have long-term life due to corrosion resistance. In this paper, we developed optimal design module of laminate for CNG composite pressure vessel winding E-glass/epoxy based on Von-Mises yield criterion, Tsai-Hill theory and stress ratio using finite element method and ANSYS RSM(Response Surface Method).

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Shape Design Sensitivity Analysis of Thermal Conduction Problems using Commercial Software ANSYS (상용 소프트웨어 ANSYS를 이용한 열전도문제의 형상설계 민감도 해석)

  • Choe, Ju-Ho
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.3 s.174
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    • pp.645-652
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    • 2000
  • A method for shape design sensitivity analysis is proposed utilizing commercial software ANSYS for thermal conduction problems. While the sensitivity formula is derived analytically by introduing adjoint variable concept, sensitivity calculation in practice as well as the primal and adjoint solution of thermal conduction is performed using the ANSYS very easily. Since the formula always takes boundary integral form, sensitivity evaluation in ANSYS requires a little more addition of post-processing routine which involves evaluation of boundary variable from the obtained solution. Though the BEM has been used as a better tool for this purpose, the present study shows it can also be calculated using any kind of analysis code such as ANSYS since the formula is based on analytic nature. Therefore the present study provides a new and efficient way of optimization which was not possible before using commercial software. The usefulness of the method is illustrated via a weight minimization problem of thermal diffuser.