Abstract
A new model which extends previous studies and includes the
interaction between enveloping gas and an array of droplets has
been developed and presented in a previous paper. The model
incorporates the probability density function of atomized metallic
droplets into the heat transfer equations. The main thrust of the
model is that the gas temperature was not predetermined and
calculated empirically but calculated numerically based on heat
balance consideration. In this paper, the accuracy of the
numerical model and the applicability of the model as a predictive
tool have been investigated by comparing experimental and
calculated results for the powder particles of 12Cr-Mo-V steel.
The study is also focusing on some aspects of the process which
are not available experimentally, e.g. the effect of undercooling
and gas/metal ratio on the solidification. The important effect of
these parameters has been illustrated.A comparison between the
numerical model and the experimental results shows an excellent
agreement and demonstrates the validity of the present model, e.g.
the calculated gas temperature which has an important influence on
the droplet solidification behaviour as well as the calculated
cooling rate of the droplets found to be in a good agreement with
the experimentally determined value. The fact that the present
approach of modelling is more general than previous studies opens
up new possibilities for a deeper understanding of such a process
without the limitation of experimental input parameters, e.g. gas
temperature. Finally, the present approach of modelling and its
predication illustrate the fact that quantitative results and
guidelines can be drawn from this model which can then be used as
a tool for the optimization of the process.
Original language | English |
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Journal | Modelling and Simulation in Materials Science and Engineering |
Volume | 7 |
Issue number | 3 |
Pages (from-to) | 431-446 |
ISSN | 0965-0393 |
Publication status | Published - 1999 |