Numerical simulation of local scour around bridge piers using novel inlet turbulent boundary conditions

Local scour is a common threat to structures such as bridge piers, abutments, and dikes that are constructed on natural rivers. To reduce the risk of foundation failure, the understanding of local scour phenomenon around hydraulic structures is important. The well-predicted scour depth can be used as a reference for structural foundation design and river management. Numerical simulation is relatively efficient at studying these issues. Currently, two-dimensional (2D) mobile-bed models are widely used for river engineering. However, a common 2D model is inadequate for solving the three-dimensional (3D) flow field and local scour phenomenon because of the depth-averaged hypothesis. This causes the predicted scour depth to often be underestimated. In this study, a repose angle formula and bed geometry adjustment mechanism are integrated into a 2D mobile-bed model to improve the numerical simulation of local scour holes around structures. Comparison of the calculated and measured bed variation data reveals that a numerical model involving the improvement technique can predict the geometry of a local scour hole around spur dikes with reasonable accuracy and reliability.

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Numerical Simulation of Temporal Evolution of Local Scour in Bridge Pier with Nonuniform Sediment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.3610 ◽

2011 ◽

Vol 250-253 ◽

pp. 3610-3614 ◽

Cited By ~ 1

Author(s):

Mohammad J. Aarabi ◽

Mohammad R. Chamani ◽

Amir A. Dehghani ◽

Keyvan Asghari

Keyword(s):

Numerical Simulation ◽

Time Variation ◽

Temporal Evolution ◽

Local Scour ◽

Bridge Pier ◽

Bridge Piers ◽

Nonuniform Sediment ◽

Natural Rivers

Due to economical and serviceability reasons, local scour must be considered in the design of bridge piers. Although beds of natural rivers consist of nonuniform sediments, but most researches in this subject were carried out with uniform sediments. In nonuniform sediments case, the effect of sheltering of the finer particles by the coarser ones may alter the scour process. In this paper, the time-variation of local scour with nonuniform sediments around a cylinder pier is simulated using SSIIM software. This study shows that the SSIIM is capable of predicting the temporal evolution of local scour in bridge piers with nonuniform sediments.

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Numerical Simulation of the Flow and Local Scour Process around Single and Complex Bridge Piers

International Journal of Civil Engineering ◽

10.1007/s40999-016-0137-8 ◽

2016 ◽

Vol 16 (5) ◽

pp. 475-487 ◽

Cited By ~ 13

Author(s):

Mahdi Alemi ◽

Rodrigo Maia

Keyword(s):

Numerical Simulation ◽

Local Scour ◽

Bridge Piers

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Shape Optimization and Strength Evaluation of Metal Welded Bellows Wave of Mechanical Seal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.1377 ◽

2008 ◽

Vol 33-37 ◽

pp. 1377-1382 ◽

Cited By ~ 2

Author(s):

Halida Musha ◽

Mamtimin Gheni ◽

Buhalqam

Keyword(s):

Numerical Simulation ◽

Bone Mass ◽

Boundary Conditions ◽

Shape Optimization ◽

Reaction Diffusion ◽

Mechanical Seal ◽

Forming Process ◽

Strength Evaluation ◽

Fem Method ◽

Initial Load

In this paper, the iBone (Imitation Bone) model which is coupled with Turing reaction-diffusion system and FEM, is used. The numerical simulation of bone forming process by considering the osteoclasts and osteoblasts process are conducted. The bone mass is increased with increase of the initial load value, then fibula and femur bones are obtained respectively by keeping the required bone forming value. The new S shape wave of metal welded bellow of mechanical seal are designed based on the the optimization results through this method. The S shape and V shape both were analyzed with FEM method. The same boundary conditions were given for two types of wave. The results are shown that the stresses mainly concentrated on the welded area. It is interesting that the value of the stresses of the two types of wave basically same. However, compressibility of the two types of wave is very different at the same computation stage. The compressibility of S shape wave was higher than V shape.

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