Study of an Additively Manufactured Permanent Strainer for Turbomachinery Application

Abstract Temporary inlet strainers are widely used during commissioning phase in turbomachinery applications to prevent dirt or debris from entering the machine. However, in the last years, there has been a growing request for permanent filters to be kept in the suction line and for this reason it is necessary to adapt the strainer design to the new operational requirements. Additive manufacturing technology was used to develop an innovative geometry and to pursue the optimization of the pressure drop and fatigue life, leveraging on the freedom of design given by metal laser-powder bed fusion (L-PBF). CFD analyses investigated the behavior of the strainer in terms of pressure drop and fluid dynamics optimization considering the potential accumulation of dirt around the strainer. FEM simulations were carried out to evaluate the mechanical resistance and fatigue life. An experimental campaign was conducted to validate the CFD numerical simulations with different operating conditions, using an additive manufactured filters made by nickel based super alloy. Finally, a conventional temporary conical strainer was tested to have a baseline for a direct comparison with the new filter. This innovative geometry demonstrated successful results showing a distinct decrease in pressure drop at increasing levels of clogging.