Fig. 4
![Top: passage-averaged LES fields of the velocity magnitude in the r−ϑ plane (only radial and tangential components) at 77% of the diffuser span from the hub side for the design (a) and off-design (b) conditions, normalized using the tangential velocity of the impeller blades at their trailing edge, u2. Bottom: passage-averaged profiles of the velocity component, ut, tangential to the PS of blade 5 along the line f in Fig. 3 for the design (c) and the off-design (d) conditions (•: experiments by Boccazzi et al. [26]; : present computations). The horizontal axis refers to the distance, xn, from the PS of blade 5, scaled by the local width of the diffuser channel, h.](https://asmedc.silverchair-cdn.com/asmedc/content_public/journal/fluidsengineering/138/12/10.1115_1.4033843/10/fe_138_12_121101_f004.png?Expires=1716944597&Signature=emYvie9FpYE9f67-~WZMlXN0QmVcvNkfO0Gk0XcB~K0MuCu9ao29xVUXx6GtgHUSvlb8n6hq2Zuk9r6~VhKqfFTbKRyW45-Gkprnqf6by99pVr1sC~3fsOqm7RDTGYtV~sY9rmQ4uO704dAENsAMA4FkBAN7FBpy57~rQ0rk91bsDu1sEV1Fa-HyUe19FP0UfFZTdwnP0IL63vPNc5xWym6twksoyySofvTuD1DzdSdPkdLa339RfedDyZPxR2z67o0ts5QFCzL99EC47rlI91m2hjhjYg2VUJshjJqu-Lq4~ChqyYKpp3MZGm~Z2yiy7niJPAGS8azVUdsaRlzutA__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Top: passage-averaged LES fields of the velocity magnitude in the plane (only radial and tangential components) at 77% of the diffuser span from the hub side for the design (a) and off-design (b) conditions, normalized using the tangential velocity of the impeller blades at their trailing edge, u2. Bottom: passage-averaged profiles of the velocity component, ut, tangential to the PS of blade 5 along the line f in Fig. 3 for the design (c) and the off-design (d) conditions (: experiments by Boccazzi et al. [26]; 
: present computations). The horizontal axis refers to the distance, xn, from the PS of blade 5, scaled by the local width of the diffuser channel, h.
