Aircraft engine impeller with exducer shroud forward sweep
AssigneePratt & Whitney Canada Corp.
InventorHien Duong
Life of this patent
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Abstract
An impeller is provided for a centrifugal compressor of an aircraft engine. The impeller includes an impeller hub and an impeller shroud having an inducer portion, an exducer portion and a bend portion interposed between the inducer portion and the exducer portion. The impeller shroud is swept forwardly in the exducer portion, the impeller shroud and the impeller hub define a gap extending through the inducer portion, the bend portion and the exducer portion and the gap is characterized as having a passage area that exhibits about a 34.375% increase from 10% of the shroud chord to 45% of the shroud chord and exhibits about a −31.1628% decrease from 45% of the shroud chord to 92.5% of the shroud chord.
Claims14
An impeller for a centrifugal compressor of an aircraft engine, the impeller comprising:
- an impeller hub;
- and
- an impeller shroud having an inducer portion, an exducer portion and a bend portion interposed between the inducer portion and the exducer portion,
- the impeller shroud being swept forwardly in the exducer portion by a greater degree than any degree of forward sweep of the impeller hub such that a maximum forward sweep angle of the impeller shroud from a zero sweep point of the impeller shroud exceeds a maximum forward sweep angle of the impeller hub from a zero sweep point of the impeller hub,
- the impeller shroud and the impeller hub defining a gap extending through the inducer portion, the bend portion and the exducer portion, and
- the gap being characterized as having a passage area that exhibits a 34.375% increase from 10% of a shroud chord to 45% of the shroud chord and exhibits a −31.1628% decrease from 45% of the shroud chord to 92.5% of the shroud chord,
- wherein the impeller shroud is swept forwardly by an angle of 15° or 20° in the exducer portion from the zero sweep point of the impeller shroud and the impeller hub is swept forwardly by an angle of 10° in the exducer portion from the zero sweep point of the impeller hub.
An impeller for a centrifugal compressor of an aircraft engine, the impeller comprising:
- an impeller hub comprising impeller vanes;
- and
- an impeller shroud having an inducer portion, an exducer portion and a bend portion interposed between the inducer portion and the exducer portion,
- the impeller shroud and trailing edges of each of the impeller vanes being correspondingly swept forwardly by a greater degree than any degree of forward sweep of the impeller hub and away from the impeller hub in the exducer portion such that a forward sweep angle of the impeller shroud from a zero sweep point of the impeller shroud exceeds a forward sweep angle of the impeller hub from a zero sweep point of the impeller hub,
- wherein the impeller shroud is swept forwardly by a maximum angle of 15° or 20° in the exducer portion from the zero sweep point of the impeller shroud and the impeller hub is swept forwardly by an angle of 10° in the exducer portion from the zero sweep point of the impeller hub.
A gas turbine engine of an aircraft, the gas turbine engine comprising:
- a diffuser having an upstream portion and a downstream portion;
- and
- an impeller upstream from the diffuser and comprising an impeller hub comprising impeller vanes and an impeller shroud having an inducer portion, an exducer portion and a bend portion interposed between the inducer portion and the exducer portion,
- the impeller shroud and trailing edges of each of the impeller vanes being correspondingly swept forwardly by a greater degree than any degree of forward sweep of the impeller hub and away from the impeller hub in the exducer portion such that a forward sweep angle of the impeller shroud from a zero sweep point of the impeller shroud exceeds a forward sweep angle of the impeller hub from a zero sweep point of the impeller hub,
- the upstream portion of the diffuser being angled to smoothly interface with forward sweeps of the impeller shroud and the trailing edges of each of the impeller vanes, and
- the downstream portion of the diffuser being arranged in parallel with a gas turbine engine center axis,
- wherein the impeller shroud is swept forwardly by a maximum angle of 15° or 20° in the exducer portion from the zero sweep point of the impeller shroud and the impeller hub is swept forwardly by an angle of 10° in the exducer portion from the zero sweep point of the impeller hub.
Dependencies are inferred from the claim text.