International Journal of Fluid Dynamics (2000), Vol. 4, Article 3

Effects of Space Environment on Flow and Concentration during Directional Solidification

C. BENJAPIYAPORN, V. TIMCHENKO, E. LEONARDI and G. DE VAHL DAVIS

School of Mechanical and Manufacturing Engineering,
The University of New South Wales,  Sydney, NSW, Australia

H. C. DE GROH III

NASA Glenn Research Center,  Cleveland OH, USA

(First Received 8th February 2000; and in revised form 15th June 2000. Published 1st August 2000.)


Abstract

A study of directional solidification of a weak binary alloy (specifically, Bi - 1 at%* Sn) based on the fixed grid single domain approach is being undertaken.  The enthalpy method is used to solve for the temperature field over the computational domain including both the solid and liquid phases;  latent heat evolution is treated with the aid of an effective specific heat coefficient.  A source term accounting for the release of solute into the liquid during solidification has been incorporated into the solute transport equation.  The vorticity-stream function formulation is used to describe thermo-solutal convection in the liquid region.

In this paper we numerically investigate the effects of g-jitter on directional solidification.  A background gravity of 1 mg has been assumed, and new results for the effects of periodic disturbances over a range of amplitudes and frequencies on solute field and segregation have been presented.

* at% = atomic percent


Keywords

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Abstract

 Next Section: Introduction

 2. Mathematical Formulation

 3. Numerical Method

 4. Validation

 5. Results and Discussion

 6. Conclusion

Acknowledgements

References