Abstract—This work presents an investigation on a flow phenomenon marked by in-plane velocity non-uniformity associated with a ported shroud turbocharger compressor observed upstream of the compressor inlet at lower operating speeds. The effect of structural struts in the ported shroud (PS) cavity and the location of the volute tongue on velocity non-uniformity is studied in this paper by numerically modelling the complete compressor stage using a (Un)steady Reynolds Averaged Navier-Stokes (RANS & URANS) approach. The results show that the amplitude of in-plane velocity non-uniformity is reduced by removing the struts from the PS cavity. Furthermore, the change in location of the volute tongue is shown to either substantially diminish or enhance the amplitude of velocity non-uniformity based on the relative position of the volute tongue and the struts. The study concludes that the velocity non-uniformity is dependent on the coupled effect of volute tongue and the strut position in the PS cavity.