Quasi-stationary numerical model of atomized metal droplets. I: model formulation

Abstract

A mathematical model for accelerating powder particles by a gas and for their thermal behaviour during flight has been developed. Usually, dealing with the solidification of metal droplets, the interaction between an array of droplets and the surrounding gas is not integrated into the modelling of such a process, for example, in the literature the gas temperature is often modelled by an empirical expression. In this model, however, the interaction between the enveloping gas and an array of droplets has been coupled and calculated numerically. The applicability of the empirical relation of the gas temperature proposed in the literature has been discussed in relation to the model. One of the major advantages of this modelling is that it provides a tool to predict the thermal behaviour of droplets during flight without the need for experimental parameters, i.e. gas temperature. Furthermore, the model predicts the effect of process parameters on the size distribution, temperature, velocity histories, fraction-solid and cooling rate for all droplet sizes characterizing the complete droplet size distribution.