| 摘要 |
<p>A centripetal turbine (1) comprises a housing (3) and a turbine wheel (4) mounted within the housing (3) and having turbine blades (5). The housing (3) defines an annular inlet passageway (7) arranged around a portion of the turbine wheel (4), and an outlet passageway (8) which has a generally cylindrical portion arranged around a portion of the turbine wheel (4). The housing (3) also defines a curved annular shoulder (9) curving radially outwards from the generally cylindrical portion of the outlet passageway (8) to the annular inlet passageway (7). The radially outer edge of each turbine blade (5) has a first portion (11) adjacent the generally cylindrical portion of the outlet passageway (8), and a second curved portion (12) adjacent the curved annular shoulder (9). The housing (3) is provided with an annular layer (13) of an abradable material covering substantially all of the substantially cylindrical portion of the outlet passageway (8) but at most only a relatively small annular portion of the curved shoulder (9) adjacent the cylindrical portion of the outlet passageway (8).</p> |
