A Mathematical Model to Study the Effect of Different Variables on the Potential Distribution in a Damaged Metal/Organic Coating System Using FEM

2019 ◽  
Vol 24 (1) ◽  
pp. 101-113 ◽  
Author(s):  
Rodrigo Montoya ◽  
Violeta Barranco ◽  
Noemi Carmona ◽  
Juan C. Galvan
Keyword(s):  
Mathematical Model ◽  
Potential Distribution ◽  
Organic Coating ◽  
Coating System ◽  
Metal Organic

An Experimental and Finite Element Modeling Approach to Determining Degradation of Aircraft Coating Systems

2020 ◽  
Author(s):  
Steve Policastro ◽  
Erick Iezzi ◽  
Carlos Hangarter ◽  
Rachel Anderson ◽  
Attilio Arcari ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Environmental Parameters ◽  
Barrier Properties ◽  
Organic Coating ◽  
Coating System ◽  
Coating Properties ◽  
Surface Pretreatment ◽  
System Properties ◽  
Service Environments ◽  
Paint Removal

In order to delay the onset of corrosion structures subjected to atmospheric degradation, such as aircraft, exterior metal surfaces are frequently covered in a corrosion prevention organic coating system. Organic coating systems, in many cases, provide a reservoir of corrosion inhibitors along with establishing a critical electrolyte barrier between the atmosphere and the structure. These coating systems include a surface pretreatment, a primer barrier layer that can contain a sacrificial inhibitor additive, and a topcoat that also provides corrosion barrier properties and other additives for color. Improving our understanding, and modeling how these coating properties change, as a function of exposure to a variety of service environments can decrease maintenance costs associated with paint removal, and re-painting. A model that can incorporate the fundamental effects of various environmental parameters can provide damage predictions based upon the measured environmental data.To that end, the initial phase of this program has focused on testing and monitoring a US Navy aircraft coating system, exposed to a variety of degradation conditions that simulate the extreme ranges of environmental stresses expected to be seen in-service. Coating condition was monitored using electrochemical impedance spectroscopy (EIS) and characterized using equivalent-circuit models so that changes to the coating system properties could be quantified and tracked over time.

Numerical Study on Electric Characteristics and Thermal Stresses of Solid Oxide Fuel Cells

2012 ◽  
Author(s):  
Pengfei Fan ◽  
Xiongwen Zhang ◽  
Guojun Li
Keyword(s):  
Mathematical Model ◽  
Finite Element ◽  
Thermal Stress ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cells ◽  
Temperature Profile ◽  
Potential Distribution ◽  
Electrical Potential ◽  
Solid Oxide ◽  
Oxide Fuel

A generalized, three-dimensional (3D) mathematical model of solid oxide fuel cells (SOFCs) for various geometries is constructed in this paper. A finite-volume method is applied to calculate the electric characteristics, which is based on the fundamental conservation law of mass, energy and electrical charge. The electrical potential distribution, the current density distribution, the concentrations distribution of the chemical species and the temperature profile are calculated by solving the governing equations of a single-unit model with double channels of co-flow and counter-flow pattern using the commercial computational fluid dynamic software Fluent. The internal steam reforming and the water shift reactions are taken into account in the mathematical model. The Knudsen diffusion is considered for computation of the gases diffusion in the porous electrodes and the concentration overpotential. The Butler-Volmer equation and the function of the reaction gases composition for the exchange density are used in the model to analyze the activation overpotential. Numerical simulations are performed for a planar geometry solid oxide fuel cell and the detailed features of the temperature, the electrical potential distribution and the gases composition are illustrated. The simulation results agree well with the Benchmark results for planar configuration. With the simulated temperature profile in the planar SOFC, the finite-element method is employed to calculate the thermal stress distribution in the planar solid oxide fuel cell. A 3D finite-element model consists of positive electrode-electrolyte-negative electrode (PEN) and interconnects assembly is constructed by using commercial finite-element code Abaqus. The effects of temperature profile, electrodes and electrolyte thickness, and coefficients of thermal expansion (CTE) mismatch between components are characterized. The calculated results indicate that the maximum stress appears on the electrode and electrolyte interface. The value and distribution of the thermal stress are the functions of the applied materials CTE, applied temperature profiles and the thicknesses of electrode and electrolyte. The calculated results can be applied as the guide for the SOFC materials selection and the SOFC structure design.

Probing the Buried Metal-Organic Coating Interfacial Reaction Kinetic Mechanisms by a Hydrogen Permeation Based Potentiometric Approach

2016 ◽  
Vol 163 (13) ◽  
pp. C778-C783 ◽  
Author(s):  
Dandapani Vijayshankar ◽  
Abdulrahman Altin ◽  
Claudia Merola ◽  
Asif Bashir ◽  
Eberhard Heinen ◽  
...  
Keyword(s):  
Interfacial Reaction ◽  
Reaction Kinetic ◽  
Hydrogen Permeation ◽  
Organic Coating ◽  
Kinetic Mechanisms ◽  
Metal Organic

scholarly journals Modification, Degradation and Evaluation of a Few Organic Coatings for Some Marine Applications

2020 ◽  
Vol 1 (3) ◽  
pp. 408-442
Author(s):  
Guang-Ling Song ◽  
Zhenliang Feng
Keyword(s):  
Corrosion Protection ◽  
Environmental Influence ◽  
Corrosion Damage ◽  
Cost Effective ◽  
Evaluation Methods ◽  
Organic Coating ◽  
Organic Coatings ◽  
Coating System ◽  
Marine Applications

Organic coatings for marine applications must have great corrosion protection and antifouling performance. This review presents an overview of recent investigations into coating microstructure, corrosion protection performance, antifouling behavior, and evaluation methods, particularly the substrate effect and environmental influence on coating protectiveness, aiming to improve operational practice in the coating industry. The review indicates that the presence of defects in an organic coating is the root cause of the corrosion damage of the coating. The protection performance of a coating system can be enhanced by proper treatment of the substrate and physical modification of the coating. Environmental factors may synergistically accelerate the coating degradation. The long-term protection performance of a coating system is extremely difficult to predict without coating defect information. Non-fouling coating and self-repairing coatings may be promising antifouling approaches. Based on the review, some important research topics are suggested, such as the exploration of rapid evaluation methods, the development of long-term cost-effective antifouling coatings in real marine environments.

Effect of slurry mechanical damage on the properties of an organic coating system

2009 ◽  
Vol 203 (19) ◽  
pp. 2974-2981 ◽  
Author(s):  
E. Scrinzi ◽  
S. Rossi ◽  
F. Deflorian
Keyword(s):  
Mechanical Damage ◽  
Organic Coating ◽  
Coating System
Sign in / Sign up

Export Citation Format

Share Document