APPLICATION OF MATHEMATICAL MODELS TO DEVELOPMENT OF NEW OPEN MOULD CONVEYOR INGOT CASTING TECHNOLOGY
The end result of mathematical modelling of casting processes should be to improve their performance either through optimisation, development or invention of new processes. This paper describes various models, their important role, development and application during the development of two successful ingot casting machine technologies. Millions of tonnes of aluminium are produced on open mould chain conveyor ingot casting machines every year. Operators of these machines are interested in reducing the oxide levels in the ingots and reducing production costs by improving the productivity of the machines. Ingot casting machine filling systems present challenges to conventional mesh based flow modelling packages. Difficulties include the handling of multiple moving surfaces (fluid and solid) and prediction of oxide generation. Smooth Particle Hydrodynamic (SPH) modelling has a number of advantages in this regard and was applied to the problem. SPH models were used as a design tool in conjunction with experimental testing. The model flow and oxide content predictions were verified on a full scale system leading to a patented low dross filling system (CASTfill). The ingot/mould interface heat transfer was studied and measurements made of air gap formation and mould deformation. Relatively simple 2D inverse and 3D thermal models were used to gain insight by conducting simple sensitivity studies. The air gap formation controls the heat flow and the solidification time however air gap prediction is a leading edge modelling problem. Alsim, a fully coupled 3D thermal stress model capable of predicting ingot and mould deformation and air gap formation was found to be capable of predicting the complex mould deformation, the measured air gap formation and solidification times for a variety of conditions with a high degree of accuracy. A new patented mould design (CASTmould) with reduced ingot solidification times in order to achieve greater production rates was the result of this work. The new filling system design is being used in 2 smelters in Australia and the new mould has also been tested in production. Finally, some thoughts and suggestions on the role of modelling in this type of project are given.
chain conveyor casting oxidation air gap filling heat flow
J. Grandfield T. Nguyen P. Rohan V. Nguyen M. Prakash P. Cleary
CRC for CAST Metals Manufacturing (CAST) CSIRO, Clayton, Victoria, 3169, Australia
国际会议
大连
英文
701-714
2007-08-19（万方平台首次上网日期，不代表论文的发表时间）