Alessio Basso, Project Leader in TWI’s Numerical Modelling and Optimisation section, recently attended the UK Fluids Conference, held between 27-29 August at the University of Cambridge. The conference brought together experts involved in fluid mechanics research.
The conference covered a wide range of topics from computational fluid dynamics (CFD) modelling and computational methods, to turbulence and non-Newtonian simulations, as well as general industrial flow applications.
Alessio gave a presentation titled “CFD modelling to simulate the direct laser metal deposition (DLMD) process”, which explored an effective methodology to predict DLMD, particularly the co-axial powder-bed fusion process.
In a DLMD process, CFD simulation plays a vital role in determining the trajectory, mass flow rate and velocity distribution of metal particles, considering the complex flow interactions between the carrier gas, the nozzle gas and shield gas. CFD can also predict the local heat transfer and subsequent particle melting efficiency, which in turn, can determine the overall lack-of-fusion in the deposited material.
The methodology proposed using a validated simulation tool in order to achieve the desired results, such as the distortion of deposited material to be below a maximum pre-defined threshold. This is a unique way to optimise the process working parameters, for example laser power or the standoff distance between nozzle and substrate. The validated results showed the particle trajectories and mass flow rate distributions at different inlet gas velocities.