Radial turbomachine with axial thrust compensation

Radial turbomachine with axial thrust compensation, comprising:

• a fixed casing (3);
• a plurality of main concentric bladed rings (9′, 9″, 9′″, 9″″) arranged in the fixed casing (3) around a central axis (X-X);
• a plurality of auxiliary concentric bladed rings (15′, 15″, 15′″) arranged in the fixed casing (3) around said central axis (X-X);
• wherein the auxiliary bladed rings (15′, 15″, 15′″) are radially alternated with the main bladed rings (9′, 9″, 9′″, 9″″);
• wherein blades (19) of said main bladed rings (9′, 9″, 9′″, 9″″) and of said auxiliary bladed rings (15′, 15″, 15′″) delimit a radial path (16) for a working fluid;
• at least one rotor (2, 2′) comprising a rotor disc (6, 6′) and a rotation shaft (4, 4′, 4″) integral with the rotor disc (6, 6′) and rotatable in the fixed casing (3) around the central axis (X-X), wherein the rotor disc (6, 6′) carries, on a front face (7, 7′), the main bladed rings (9′, 9″, 9′″, 9″″);
• wherein said main (9′, 9″, 9′″, 9″″) and auxiliary (15′, 15″, 15′″) bladed rings delimit, with the rotor disc (6, 6′), a plurality of concentric front main chambers (30, 33, 35, 36) at different pressures;
• wherein a plurality of concentric rear annular main chambers (41′, 41″, 41′″, 41″″), each in fluid communication with a respective front main chamber (30, 33, 35, 36) and at the same pressure as said front main chamber (30, 33, 35, 36), is delimited between a rear face (8, 8′) of the rotor disc (6, 6′) and the fixed casing (3);
• wherein a rear annular area (A_1p, A_2p, A_3p, A_4p, A′_4p) of the rotor disc (6, 6′) delimiting one of the rear annular main chambers (41′, 41″, 41′″, 41″″) is equal to or substantially equal to a front area (A_1f, A_2f, A_3f, A_4f) of said rotor disc (6, 6′) delimiting a respective front main chamber (30, 33, 35, 36), so that the force exerted by the pressure of the working fluid in each rear annular main chamber (41′, 41″, 41′″, 41″″) substantially balances the force exerted by the pressure of the working fluid in the respective front main chamber (30, 33, 35, 36).