Simulation of convective flow and thermal conditions during ultrasonic treatment of an Al-2Cu alloy
| Autor: | Damian McGuckin, Paul Croaker, Gui Wang, Matthew S. Dargusch, David H. StJohn |
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| Rok vydání: | 2017 |
| Předmět: |
010302 applied physics
Convection Materials science Sonotrode General Computer Science Metallurgy Nucleation General Physics and Astronomy 02 engineering and technology General Chemistry Mechanics 021001 nanoscience & nanotechnology 01 natural sciences Computational Mathematics Temperature gradient Acoustic streaming Mechanics of Materials 0103 physical sciences Thermal Heat transfer General Materials Science Ultrasonic sensor 0210 nano-technology |
| Zdroj: | Computational Materials Science. 134:116-125 |
| ISSN: | 0927-0256 |
| DOI: | 10.1016/j.commatsci.2017.03.041 |
| Popis: | Grain refinement of an Al-2Cu alloy using ultrasonic treatment was investigated numerically. A finite element model coupling fluid flow and heat transfer was developed and validated by comparing the results of both numerical simulations and physical experiments. The model successfully describes hydrodynamic fields generated by ultrasonic treatment and its influence on heat transfer. The simulations were used to study the influence of the duration of ultrasonic treatment and the associated acoustic streaming on convection and the resulting temperature distribution. It was revealed that a relatively cold sonotrode applied during ultrasonic treatment for up to 4 min created a casting environment that promoted crystal nucleation and enabled their growth and survival during transport of these grains into the bulk of the melt by strong convection. The enhanced convection established a low temperature gradient throughout the melt which favours the formation of an equiaxed grain structure. Therefore, the convection induced by acoustic streaming plays a critical role in facilitating nucleation, growth, and transport of grains. |
| Databáze: | OpenAIRE |
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