Prediction of Cavitation Erosion and Residual Stress of Material Using Cavitating Flow Simulation with Bubble Flow Model

We developed the new method for predicting a region of compressive residual stress on the weld surface after water jet peeing (WJP), which is a preventive maintenance technology for nuclear power plants. A cavitating jet is impinged on the weld surfaces of structures in a nuclear reactor. Bubble collapse impact causes plastic deformation of the weld surface, and changes the residual stress from tensile to compressive. Compressive residual stress prevents the occurrence of stress corrosion cracking (SCC) on the weld surface. A cavitating jet vertically injected into a submerged flat plate was investigated. Tensile stress was introduced onto the surface of the stainless steel plate by grinding before WJP in the experiment. We numerically simulated impulsive bubble pressure that varied by microseconds in the cavitating jet with the “bubble flow model”. The bubble flow model simulates the abrupt time-variations in the radius and inner pressure of bubbles based on the Rayleigh-Plesset equation in a cavitating flow. The cavitation collapse energy was estimated based on the bubble pressure. The cavitation collapse energy was compared with the measured compressive residual stress on the flat plate after WJP. The radial range of the compressive residual stress from the jet center axis is one of the most important measures of performance of WJP. The radial range of the cavitation collapse energy corresponded to that of compressive residual stress with a prediction error of +/− 20% under different conditions of jet velocity and the distance between the jet nozzle and plate surface. The results confirmed that the method we developed for predicting the region of compressive residual stress after WJP was valid.

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Flood Forecasting and Stream Flow Simulation of the Upper Awash River Basin, Ethiopia Using Geospatial Stream Flow Model (GeoSFM)

Springer Geography - Landscape Dynamics, Soils and Hydrological Processes in Varied Climates ◽

10.1007/978-3-319-18787-7_18 ◽

2015 ◽

pp. 367-384 ◽

Cited By ~ 3

Author(s):

Shimelis Behailu Dessu ◽

Abdulkarim Hussein Seid ◽

Anteneh Z. Abiy ◽

Assefa M Melesse

Keyword(s):

River Basin ◽

Stream Flow ◽

Flow Model ◽

Flow Simulation ◽

Flood Forecasting ◽

Awash River Basin

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Using a Coupled Thermal/Material Flow Model to Predict Residual Stress in Friction Stir Processed AlMg9Si

Journal of Materials Engineering and Performance ◽

10.1007/s11665-015-1402-8 ◽

2015 ◽

Vol 24 (3) ◽

pp. 1305-1312 ◽

Cited By ~ 3

Author(s):

C. Hamilton ◽

M. St. Węglowski ◽

S. Dymek ◽

P. Sedek

Keyword(s):

Residual Stress ◽

Material Flow ◽

Flow Model ◽

Friction Stir

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The Analysis of Traffic Flow Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.237 ◽

2013 ◽

Vol 380-384 ◽

pp. 237-240

Author(s):

Xiao Wei Wei

Keyword(s):

Traffic Flow ◽

Traffic Control ◽

Complex Analysis ◽

Flow Model ◽

Flow Simulation ◽

Urban Traffic ◽

Traffic Condition ◽

Traffic Flow Model ◽

Real Time Traffic ◽

Dual Channel

With worsening traffic condition in large and medium-sized cities, it has become one of the most important steps for the urban traffic strategy to solve the traffic problems. Since the urban traffic is a complex system in various factors and huge scale, to establish related mathematical model through computer numerical simulation is a significant solution to the comprehensive problems of complex analysis, decision and planning. At present researches on the problems have been achieved in many foreign countries, but domestic research is not enough, especially in the practical application. The macroscopic traffic flow model and microscopic traffic flow model are described and cellular automaton model, dual channel decision model and car-following model are analyzed in this paper, prediction of the ideal traffic flow and trip distribution is consequently concluded, which deepen the understanding to the traffic flow of various phenomenon intrinsic mechanism and predict most closely to the actual situation of traffic flow, which can make fundamental work for traffic flow simulation and for real-time traffic control[1-3].

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Photoresist flow simulation using the viscous flow model

International Conference on Simulation of Semiconductor Processes and Devices, 2003. SISPAD 2003. ◽

10.1109/sispad.2003.1233633 ◽

2003 ◽

Cited By ~ 1

Author(s):

Won-young Chung ◽

Tai-kyung Kim ◽

Young-tae Kim ◽

Byung-joon Hwang ◽

Young-kwan Park ◽

...

Keyword(s):

Viscous Flow ◽

Flow Model ◽

Flow Simulation

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Numerical Prediction of Various Cavitation Erosion Mechanisms

Journal of Fluids Engineering ◽

10.1115/1.4045365 ◽

2020 ◽

Vol 142 (4) ◽

Author(s):

Ignacijo Biluš ◽

Marko Hočevar ◽

Matevž Dular ◽

Luka Lešnik

Keyword(s):

Experimental Work ◽

High Speed ◽

Cavitation Erosion ◽

Cavitating Flow ◽

Numerical Prediction ◽

Quantitative Prediction ◽

Navier Stokes ◽

Erosion Mechanisms ◽

Recent Experimental Work ◽

Collapse Phase

Abstract Numerical prediction of cavitation erosion is a great scientific and technological challenge. In the past, many attempts were made—many successful. One of the issues when a comparison between a simulation and erosion experiments is made, is the great difference in time scale. In this work, we do not attempt to obtain quantitatively accurate predictions of erosion process but concentrate qualitatively on cavitation mechanisms with quantitative prediction of pressure pulses which lead to erosion. This is possible, because of our recent experimental work on simultaneous observation of cavitating flow and cavitation erosion by high speed cameras. In this study, the numerical simulation was used to predict details of the cavitation process during the vapor collapse phase. The fully compressible, cavitating flow simulations were performed to resolve the formation of the pressure waves at cavitation collapse. We tried to visualize the mechanisms and dynamics of vapor structures during collapse phase at the Venturi geometry. The obtained results show that unsteady Reynolds-averaged Navier–Stokes (URANS) simulation of cavitation is capable of reproducing four out of five mechanisms of cavitation erosion, found during experimental work.

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