The History Physical Fundamentals of Casting
The theoretical fundamentals of heat conduction in solid matter were developed by Jean Baptiste Joseph Fourier at the Ecole Polytechnique in Paris. His thesis, “The Analytical Theory of Heat”, received awards in 1822. It has provided the basis for all subsequent calculations of heat conduction and transfer in solid materials. The French physicist and engineer Claude-Louis Navier, and the Irish mathematician and physicist George Gabriel Stokes, subsequently provid- ed the basics of flow dynamics. The differential equations describing fluid flow are now known as the Navier -Stokes equations. The basic equations describing diffusion were de- veloped by Adolf Fick, who worked during the 19th century at the University of Zurich and published them in 1855.
Brief History of Simulation
In the 1950s, V. Paschkis used analog computers to predict the movement of a solidification front in one or two dimen- sions. With the development of the first digital computers, Dr. K. Fursund was the first who used computers to solve cast- ing process related problems (penetration of steel into mold sand), in 1962. Three years later, J. G. Hent zel and J. Keverian
published their ground-breaking work about two dimensional simulation of steel casting solidification. They utilized a pro- gram developed by General Electric to simulate heat transfer.
In 1968, Ole Vestby programmed a 2-D model to evaluate temperature distributions during welding, using, for the first time, the finite difference metho d. Two years later, Prof. V. de Lange Davies used Vestby’s program to simulate feeding distances in plate-like castings. P. N. Hansen published his thesis describing his work to predict hot tears in steel cast- ings (Fig. 2) in 1975. In the preparation of this thesis, a 3-D model was programmed for the first time.
Figure 3. Due to the lack of computer performance in the 70’s, the resolution of casting models was still questionable (see display of a low pressure die casting wheel). (Sahm and Hansen, 1984)
Figure 2. The first results of a temperature distribution in a hot tear test casting had to be painted on a wooden model, as there were no computers with color monitors in existence. (P.N. Hansen, 1975)
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Figure 4. At the end of the 80’s real castings (a steel casting hammer in this example) were calculated and compared to casting trials for the first time using programs developed at universities. This example shows calculations of the CASTS program developed by the Foundry Institute of the RWTH Aachen. (Sturm,
Schäfer and Sahm, 1988) International Journal of Metalcasting/Spring 10
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