tailieunhanh - Numerical simulation of electrochemical changes in the study of corrosion in an occluded

An experimental setup allowing pH measurements inside a confined volume representing a lapped joint was designed in our last study [1]. The pH evolution over steel surface in confined conditions was monitored. In this study, the experimental pH was compared with that calculated using a two-dimensional transport-reaction model only in the case of a confined iron surface. | Vietnam Journal of Science and Technology 56 (2A) (2018) 217-225 NUMERICAL SIMULATION OF ELECTROCHEMICAL CHANGES IN THE STUDY OF CORROSION IN AN OCCLUDED ZONE Vu Anh Quang1, *, Luu Hoang Tam1, Nguyen Nhi Tru1, Vinh-Dat Vuong1, 2, 3, Le Van Thang1, 2 1 Department of Energy Materials, Faculty of Materials Technology, HCMUT–VNUHCM 268 Ly Thuong Kiet Street, Ward 14, District 10, Ho Chi Minh City, Viet Nam 2 Materials Technology Laboratory, HCMUT–VNUHCM 268 Ly Thuong Kiet Street, Ward 14, District 10, Ho Chi Minh City, Viet Nam 3 Graduate University of Science and Technology, VAST 18 Hoang Quoc Viet Streem Cau Giay District, Ha Noi City, Viet Nam * Email: vaquang@ Received: 12 March 2018; Accepted for publication: 13 May 2018 ABSTRACT An experimental setup allowing pH measurements inside a confined volume representing a lapped joint was designed in our last study [1]. The pH evolution over steel surface in confined conditions was monitored. In this study, the experimental pH was compared with that calculated using a two-dimensional transport-reaction model only in the case of a confined iron surface. The difference between the experimental and calculated pH in the steady state was attributed to the limitation of the modelling approach, more especially concerning solid phases precipitation inside the cavity. Nevertheless, only short term (hour) experiments and simulations can be compared illustrating the necessary improvement of these basic models to predict real perforation corrosion rate at long term. Keywords: galvanized steel, lapped joint, pH measurement, numerical simulation. 1. INTRODUCTION In Viet Nam, some scientists have recently started using COMSOL Multiphysics software in their research. However, the number of studies and research areas is limited. In 2012, a COMSOL Multiphysics software application in intelligent inkjet nozzle simulation was performed by Hoang Cuong [2]. In 2014, Le Minh Thanh [3] and colleagues simulated a decrease in .