• 제목/요약/키워드: Implicit euler

검색결과 74건 처리시간 0.022초

Dynamic Analysis of a Moving Vehicle on Flexible Beam structures ( I ) : General Approach

  • Park, Tae-Won;Park, Chan-Jong
    • International Journal of Precision Engineering and Manufacturing
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    • 제3권4호
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    • pp.54-63
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    • 2002
  • In recent years, mechanical systems such as high speed vehicles and railway trains moving on elastic beam structures have become a very important issue to consider. In this paper, a general approach, which can predict the dynamic behavior of a constrained mechanical system moving on a flexible beam structure, is proposed. Various supporting conditions for the foundation support are considered for the elastic beam structure. The elastic structure is assumed to be a non-uniform and linear Bernoulli-Euler beam with a proportional damping effect. Combined differential-algebraic equation of motion is derived using the multi-body dynamics theory and the finite element method. The proposed equations of motion can be solved numerically using the generalized coordinate partitioning method and predictor-corrector algorithm, which is an implicit multi-step integration method.

A NOTE ON (p, q)-ANALOGUE TYPE OF FROBENIUS-GENOCCHI NUMBERS AND POLYNOMIALS

  • Khan, Waseem A.;Khan, Idrees A.
    • East Asian mathematical journal
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    • 제36권1호
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    • pp.13-24
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    • 2020
  • The main purpose of this paper is to introduce Apostol type (p, q)-Frobenius-Genocchi numbers and polynomials of order α and investigate some basic identities and properties for these polynomials and numbers including addition theorems, difference equations, derivative properties, recurrence relations. We also obtain integral representations, implicit and explicit formulas and relations for these polynomials and numbers. Furthermore, we consider some relationships for Apostol type (p, q)-Frobenius-Genocchi polynomials of order α associated with (p, q)-Apostol Bernoulli polynomials, (p, q)-Apostol Euler polynomials and (p, q)-Apostol Genocchi polynomials.

항공기 무장투하 안전성 검증을 위한 전산해석 (NUMERICAL SIMULATION FOR AIRCRAFT STORE SEPARATION VALIDATION)

  • 윤용현;정형석;이상현
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 추계 학술대회논문집
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    • pp.157-161
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    • 2007
  • The prediction of the safe separation of the external stores carried on military aircraft is an important task in the aerodynamic design area having the objective to define the operational, release envelopes. The major concern of this study is only safe jettison problem with ejections. This work consists of concept and some results for external store configurations. A Computational Fluid Dynamics technique is applied to calculate the aerodynamic forces. The FLUENT with an implicit Euler solver is used for the present simulations. The computational results are validated against the experimental data.

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날개꼴의 형상 최적화를 위한 유동방정식 영향 연구 (Influence of Flow Solvers On Airfoil Shape Optimization)

  • 정희택;류병석
    • 한국전산유체공학회지
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    • 제4권2호
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    • pp.67-73
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    • 1999
  • In the present paper, three types of the flow solvers were used to investigate the influence on the airfoil shape optimization. The adopted equations, i.e., Euler, thin layer Navier-Stokes and full Navier-Stokes ones. are solved using implicit LU-ADI decomposition scheme. The gradient projection method with the sinusoidal function was used as an optimization algorithm. The present numerical method was applied to the drag minimization problems under the initial shape of NACA0012 airfoils.

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날개꼴의 형상 최적화를 위한 유동방정식 영향 연구 (Influence of Flow Solvers On Airfoil Shape Optimization)

  • 정희택;류병석
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1999년도 춘계 학술대회논문집
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    • pp.171-176
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    • 1999
  • In the present paper, three types of the flow solvers were used to investigate the influence on the airfoil shape optimization. The adopted equations, i.e., Euler , thin layer Navier- Stokes and full Navier-Stokes ones, are solved using implicit LU-ADI decomposition scheme. The feasible direction algorithm with the sinusoidal function was used as an optimization algorithm. The present numerical method was applied to the drag minimization problems under the initial shape of NACA0012 airfoils.

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ON HIGHER ORDER (p, q)-FROBENIUS-GENOCCHI NUMBERS AND POLYNOMIALS

  • KHAN, WASEEM A.;KHAN, IDREES A.;KANG, J.Y.
    • Journal of applied mathematics & informatics
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    • 제37권3_4호
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    • pp.295-305
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    • 2019
  • In the present paper, we introduce (p, q)-Frobenius-Genocchi numbers and polynomials and investigate some basic identities and properties for these polynomials and numbers including addition theorems, difference equations, derivative properties, recurrence relations and so on. Then, we provide integral representations, implicit and explicit formulas and relations for these polynomials and numbers. We consider some relationships for (p, q)-Frobenius-Genocchi polynomials of order ${\alpha}$ associated with (p, q)-Bernoulli polynomials, (p, q)-Euler polynomials and (p, q)-Genocchi polynomials.

내/외재적 유한요소법을 이용한 최대추력노즐의 설계해석 (Implicit/Explicit Finite Element Method for Euler Flows Inside the Optimum Nozzle)

  • 윤웅섭;고현
    • 한국전산유체공학회지
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    • 제2권1호
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    • pp.66-72
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    • 1997
  • Optimum nozzle design exploiting the method of characteristic(M.O.C) has been in application as an efficient design methodology targeting a less weighted and short expansion nozzle. This paper treats the optimum nozzle design and the analysis of the inviscid compressible flow inside. Based on traditional Rao's method, the optimum nozzle design is coded with minor modifications for the identification of the control surface across which the mass flux should be conserved. Internal flow field is simulated numerically by M.O.C and implicit/explicit Taylor-Galerkin finite element method(F.E.M) with the aid of adaptive remeshing to capture the shock wave, hence improve the accuracy. Designed and calculated flow fields due to the separate analyses show that the mass flux predicted by optimum nozzle design with M.O.C is not conserved across the control surface and the sonic line should be located upstream of the nozzle throat. Rao's optimum nozzle design methodology exaggerates the momentum thrust and tends to overemphasize the engine performance loss.

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A New Time Stepping Method for Solving One Dimensional Burgers' Equations

  • Piao, Xiang Fan;Kim, Sang-Dong;Kim, Phil-Su;Kim, Do-Hyung
    • Kyungpook Mathematical Journal
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    • 제52권3호
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    • pp.327-346
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    • 2012
  • In this paper, we present a simple explicit type numerical method for discretizations in time for solving one dimensional Burgers' equations. The proposed method does not need an iteration process that may be required in most implicit methods and have good convergence and efficiency in computational sense compared to other known numerical methods. For evidences, several numerical demonstrations are also provided.

노심 동특성 분석 정확도 및 성능 향상을 위한 Time Step 제어방법 개선

  • 김영일;김영진;주형국;김택겸
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1997년도 추계학술발표회논문집(1)
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    • pp.79-84
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    • 1997
  • 동특성 분석 코드 시스템 PANBOX2는 시간에 대한 미분을 Implicit Euler 방법을 사용하여 근사한다. 이 경우 Local Truncation Error는 중성자속의 이차 미분에 비례한다. Time-Step-Doubling 기법을 이용하여 Local Truncation Error의 근사치를 구하고 이를 이용하여 Time Step Size를 조절해 주는 방법을 동특성 분석 코드 시스템 PANBOX2에 도입하였다. LRA와 NEACRP 제어봉 인출사고 검증문제에 대한 분석 결과, PANBOX2 시스템의 기존 방법에 비해 효과적으로 Time Step을 제어하였으며 보다 정확한 결과를 얻을 수 있었다.

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Some Properties of the Generalized Apostol Type Hermite-Based Polynomials

  • KHAN, WASEEM AHMAD
    • Kyungpook Mathematical Journal
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    • 제55권3호
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    • pp.597-614
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    • 2015
  • In this paper, we study some properties of the generalized Apostol type Hermite-based polynomials. which extend some known results. We also deduce some properties of the generalized Apostol-Bernoulli polynomials, the generalized Apostol-Euler polynomials and the generalized Apostol-Genocchi polynomials of high order. Numerous properties of these polynomials and some relationships between $F_n{^{({\alpha})}}(x;{\lambda};{\mu};{\nu};c)$ and $_HF_n{^{({\alpha})}}(x;{\lambda};{\mu};{\nu};c)$ are established. Some implicit summation formulae and general symmetry identities are derived by using different analytical means and applying generating functions.