논문 상세보기

Analysis of Empirical Constant of Eddy Viscosity by Zero- and One- Equation Turbulence Model in Wake Simulation KCI 등재

  • 언어ENG
  • URLhttps://db.koreascholar.com/Article/Detail/325363
구독 기관 인증 시 무료 이용이 가능합니다. 4,200원
해양환경안전학회지 (Journal of the Korean Society of Marine Environment and Safety)
해양환경안전학회 (The Korean Society Of Marine Environment & Safety)
초록

In this paper, the wakes behind a square cylinder were simulated using two kinds of different turbulence models for the eddy viscosity concept such as the zero- and the one-equation model in which the former is the mixing length model and the latter is the k-equation model. For comparison between numerical and analytical solutions, we employed three skill assessments: the correlation coefficient(r) for the similarity of the wake shape, the error of maximum velocity difference(EMVD) for the accuracy of wake velocity and the ratio of drag coefficient(RDC) for the pressure distribution around the structure. On the basis of the numerical results, the feasibility of each model for wake simulation was discussed and a suitable value for the empirical constant was suggested in these turbulence models. The zero-equation model, known as the simplest turbulence model, overestimated the EMVD and its absolute mean error(AME) for r, EMVD and RDC was ranging from 20.3 % to 56.3 % for all test. But the AME by the one-equation model was ranging from 3.4 % to 19.9 %. The predicted values of the one-equation model substantially agreed with the analytical solutions at the empirical mixing length scale L=0.6b1/2 with the AME of 3.4 %. Therefore it was concluded that the one-equation model was suitable for the wake simulation behind a square cylinder when the empirical constant for eddy viscosity would be properly chosen.

저자
  • Il Heum Park(School of Marine Technology, Chonnam National University)
  • Young Jun Cho(School of Marine Technology, Chonnam National University)
  • Tae Yun Kim(Office of Environment Assessment, Korea Environment Institute) Corresponding Author
  • Moon Ock Lee(School of Marine Technology, Chonnam National University)
  • Sung Su Hwang(School of Marine Technology, Chonnam National University)