Loading...

Numerical Analysis of Flow Pattern around Pile Groups (Two Piles)

Dashtpeyma, Hamed | 2013

765 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 45131 (09)
  4. University: Sharif University of Technology
  5. Department: Civil Engineering
  6. Advisor(s): Ataie Ashtiani, Behzad; Beheshti, Ali Asghar
  7. Abstract:
  8. Numerical simulations and large eddy simulations (LES) of turbulent flow around single pile, circular tandem piles, circular and square side-by-side piles at different spacing ratios (centre to centre distance to the pile diameter) with flow Reynolds number of 105 on the fixed flat-bed are presented. The calculations are performed using a computational fluid dynamics model, FLOW-3D, which solves the Navier-Stokes equations in three dimensions with finite volume method. Numerical simulations are validated by comparing the numerical results of time-averaged flow patterns around single and side-by-side piles with that of the experimental measurements. At the downstream of single pile, dimensionless vortex shedding frequency (Strouhal number) is estimated as 0.22. The maximum values of bed shear stresses around side-by-side piles at different spacing ratios are compared with the maximum values obtained through single pile. Coherent and turbulent structures are studied by using the Q criterion. Owing to the turbulent conditions and oscillations of flow, all of contours are extracted at the moment that the highest shear stress is exerted at the bed (Critical moment). Interactions of horseshoe vortices on different cases of side-by-side piles are studied. Numerical results show that the critical arrangement for which the largest bed shear stress was observed is the case with the spacing ration of 3. The maximum and minimum quantity of loading factors for different cross sections and spacing ratios of piles are discussed
  9. Keywords:
  10. Turbulent Flow ; Side-by-Side Pier ; Tandom Pier ; Computational Fluid Dynamics (CFD) ; Numerical Analysis ; Flow Patterns

 Digital Object List

 Bookmark

No TOC