Objectives and content
The objective of this project is to develop and evaluate reliable numerical methods to predict the current density distribution and consequently the deposition of reacting species in electrochemical systems of various natures and industrial relevance.
The obtained results will yield essential design tools to many branches of the electrochemical industry: plating industry (contacts, PCB's, Smart cards, spot plating, strip and wire plating, ...) where it is a major problem to obtain uniformly deposited layers on well defined places, etching industry (for micro mechanical parts in valves, watches, offset printing plates ..), anodising industry (for complex shapes in aviation and aeronautics, for high quality offset printing), electrochemical machining industry (e.g. electrochemical cutting) and the electrochemical recovery industry.
In all these electrochemical systems mass transport phenomena of charged species due to diffusion, convection and migration (electrical forces) are strongly coupled with the electrochemical reaction(s) at the electrodes. Sometimes also temperature effects are to be considered.
Based on the very promising results obtained within the scope of the Brite-EuRam-II programme, an extension of the partnership with industrial partners is essential in order to achieve, at the suggestion of the new partners, the following objectives for future application:
- Step by step development and implementation of numerical methods for solving the governing system of equations in three dimensions. This system results from the combination of the mass and charge transport equations with the uncoupled Navier-Stokes equation. Models for dilute solutions with four ions will be considered.
- Step by step extension of the developed numerical methods in two dimensional and axisymmetrical systems for theoretical description of electrochemical systems with more complex electrode processes: multicomponent solutions, homogeneous reactions in the bulk, parallel charge transfer reactions (e.g. to model alloy plating) and electrode growth. - Step by step extension of the developed numerical methods in two dimensional and axisymmetrical systems for theoretical description of electrochemical systems where the following phenomena are relevant: ohmic and temperature effects in electrodes, ohmic and temperature effects in the solution, temperature effects produced by electrode processes, interaction between fluid flow, heat, mass and charge transfer.
- Experimental determination of flow, mass transport, current density, thickness, temperature and potential distributions in model cells of industrial significance, for several practical electrochemical processes. - Comparison of measured and calculated data with evaluation of the limits of applicability of the obtained predictions for dilute solutions (included the possibility of correlating local properties of a deposit to local values: partial currents, potential and concentrations of interfering ions).
For its fundamental and theoretical aspects, the proposed project is basic research upstream of Industrial Research. The partnership structure contains two universities (VUB, UE), three research centres (VKI, WIT, CNRS) and four industries (BEKAERT, BOSCH, HOOGOVENS, PHILIPS). VKI provides the numerical knowledge in fluid dynamics and heat transfer. VUB and WIT continue the development of two new numerical methods to solve the electrochemical models. UE will work on techniques for direct and indirect mass and heat transport measurements. In co-operation with PHILIPS and BOSCH, CNRS will provide the electrochemical data needed and study the possibility to link numerical results with properties of deposits.
Funding SchemeCSC - Cost-sharing contracts
1970 CA Ijmuiden
5600 MD Eindhoven
SO4 2AA Southampton