Numerical simulation of electrochemical mechanism of steel rebar corrosion in concrete under natural climate with time-varying temperature and humidity

The numerical simulation and experimental validations of the growth and departure of a single bubble on a horizontal heated surface during pool boiling under reduced gravity conditions have been performed here. A finite difference scheme is used to solve the equations governing mass, momentum and energy in the vapor liquid phases. The vapor-liquid interface is captured by level set method, which is modified to include the influence of phase change at the liquid-vapor interface. The effects of reduced gravity conditions, wall superheat and liquid subcooling and system pressure on the bubble diameter and growth period have been studied. The simulations are also carried out under both constant and time-varying gravity conditions to benchmark the solution with the actual experimental conditions that existed during the parabolic flights of KC-135 aircraft. In the experiments, a single vapor bubble was produced on an artificial cavity, 10 μm in diameter microfabricated on the polished silicon wafer, the wafer was heated electrically from the back with miniature strain gage type heating elements in order to control the nucleation superheat. The bubble growth period and the bubble diameter predicted from the numerical simulations have been found to compare well with the data from experiments.

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Fatigue failure analysis of a Ø14 B500C steel rebar: Metallurgical evaluation and numerical simulation

Engineering Failure Analysis ◽

10.1016/j.engfailanal.2019.03.016 ◽

2019 ◽

Vol 101 ◽

pp. 180-192 ◽

Cited By ~ 1

Author(s):

George Pantazopoulos ◽

Ioannis Pressas ◽

Athanasios Vazdirvanidis

Keyword(s):

Numerical Simulation ◽

Failure Analysis ◽

Fatigue Failure ◽

Steel Rebar ◽

Metallurgical Evaluation

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Synchronization of Complex Networks with Time-Varying Delayed Dynamical Nodes via Pinning Control

Mathematical Problems in Engineering ◽

10.1155/2012/654742 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13

Author(s):

Shuguo Wang ◽

Hongxing Yao ◽

Qiuxiang Bian

Keyword(s):

Numerical Simulation ◽

Complex Networks ◽

Pinning Control ◽

Effective Control ◽

Time Varying ◽

Time Varying Delay ◽

Control Scheme ◽

Adaptive Coupling ◽

Coupling Strengths ◽

Varying Delay

This paper investigates the pinning synchronization of nonlinearly coupled complex networks with time-varying coupling delay and time-varying delay in dynamical nodes. Some simple and useful criteria are derived by constructing an effective control scheme and adjusting automatically the adaptive coupling strengths. To validate the proposed method, numerical simulation examples are provided to verify the correctness and effectiveness of the proposed scheme.

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Numerical Simulation by CGM for Moving Force Identification

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.238.826 ◽

2012 ◽

Vol 238 ◽

pp. 826-829

Author(s):

Zhen Chen ◽

Jun Ling Han

Keyword(s):

Numerical Simulation ◽

Time Domain ◽

Bending Moment ◽

Identification Accuracy ◽

Time Varying ◽

Acceptable Solution ◽

Moving Force ◽

Ill Posed ◽

Simulation Results ◽

The Time Domain

The conjugate gradient method (CGM) is compared with the time domain method (TDM) in the paper. The numerical simulation results show that the CGM have higher identification accuracy and robust noise immunity as well as producing an acceptable solution to ill-posed problems to some extent when they are used to identify the moving force. When the bending moment responses are used to identify the time-varying loads, the identification accuracy is more obviously improved than the TDM, which is more suitable for the time-varying loads identification.

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