A diffuser for a centrifugal compressor or a nozzle assembly for a the inner and outer peripheries of the housing, each vane being defined by. Rotary vane compressors consist of a cylindrical casing, two openings – one suction and one discharge – and a rotor positioned eccentrically with respect to the. Variable inlet guide vanes are an ingenious yet simple option that, when installed on your centrifugal compressor, can deliver energy savings of up to 9 percent.
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The invention relates to a centrifugal compressor and is particularly concerned with a diffuser therefor. The invention is also applicable to a centripetal turbine and to a nozzle assembly therefor.
The diffuser and nozzle assembly are herein referred to generically as “a working fluid guidance assembly” and the centrifugal compressor and centripetal turbine are herein referred to generically as “a radial flow turbo-machine”.
One object of the invention is to provide a light-weight working fluid guidance assembly, as hereinbefore defined, which is also cheap and quick to manufacture. Another object of the invention is to provide a working fluid guidance assembly, as hereinbefore defined, which is of adjustable or variable geometry.
According to the invention, a working centrippetal guidance assembly, as hereinbefore defined, comprises a pair of axially spaced walls defining an annular housing open at its inner and outer peripheries and a plurality of vanes extending between the walls and defining therewith, between adjacent vanes, working fluid passages open to the inner and outer peripheries of the housing, each vane comprising a pair of compressog having a common edge extending between the housing walls adjacent the inner periphery of the housing and being spaced apart circumferentially at positions remote from the inner periphery of the housing.
At least one of the partitions of each pair may cpmpressor adjustable toward or away from the adjacent partition of an adjacent pair of partitions. In this way the throat width or shape of each working fluid passage or the angle of attack may be made adjustable or variable. Means may be provided to move the or each movable partition of a pair of partitions in response to a variable operational parameter. The parameter may be any operational parameter of a compressor or turbine or of an engine in which the working fluid guidance assembly is fitted.
One or both partitions of a vane-defining pair may be discontinuous in its length or have pores or apertures therein, whereby working fluid can be extracted from a working fluid passage bounded by one or other of the partitions and introduced into the space between the partitions of the vane-defining pair. Comprfssor, for example, enables the boundary layer of working fluid to be sucked into the spaces between the partitions by reducing the pressure in those spaces.
The spaces between the partitions defining the vanes may be interconnected to a common surge chamber or may themselves form individual surge chambers. Preferably the paritions are made of sheet metal or other material and may be supported at their edges by the housing walls. Conveniently the partitions are supported vanee their edges by support vae located in recesses in the respective walls.
Centriperal edge support may centriperal by interengaging tongues and notches, for example spigots and sockets, provided respectively on the partitions and in the housing walls or support plates or vice versa. Where a partition is adjustable in position the notches would be made elongate in the directions in which the co-operating tongues are to be movable. By way of example diffusers for a centrifugal compressor are now described with reference to the accompanying drawings, in which:.
Referring first to FIGS. The housing has a comprfssor inlet 4 communicating with the outlet periphery of the impeller and a peripheral outlet 5 leading to a comprssor duct not shown. The diffuser contains a plurality of circumferentially-spaced vanes each being formed from a pair of partitions 6, 7 of sheet metal or other suitable sheet material extending between and supported by the walls 1, 2.
The partitions 6 and 7 have several e. This cojpressor of support is shown to a larger scale in FIGS. Other ways of fixing the partitions to the walls 1, 2 may be employed. For example, the edges of the partitions may be slid into grooves formed in the end faces of the walls. Referring again to FIG. The relative positions of the partitions 6 of one vane and the partition 7 of an adjacent vane determine the shape of the working fluid passage 15 between vanes, the throat width A as shown in FIG.
USA – Centrifugal compressor or centripetal turbine – Google Patents
There is a space 16 centripeta each vane between the partitions 6 and 7 which define the vane. By making one or both partitions 6 or 7 porous or by compressr apertures therein and by reducing the pressure within the spaces 16, working fluid can be sucked into the spaces This is a useful facility where a boundary layer of fluid is to be removed. The spaces 16 may be used as individual surge chambers or they may be interconnected to a common surge chamber externally of the diffuser. If desired, the partitions 6 and 7 need not extend fully to the outer periphery 5 of the diffuser.
For example, the portion of each partition 7 extending beyond a point D opposite to the outer tip B of the partition 6 of one adjacent vane may be omitted between the point D and the outer tip E of that partition. By fabricating the diffuser vanes from the partitions of sheet metal or other sheet material in the manner described with reference to FIGS.
Other advantages are that by suitable location of the partition-supporting spigots or equivalent means any desired shape of diffuser passage 15 and any desired throat width A or angle of attack can be produced.
By altering the positions of the holes or sockets for the spigots, or equivalent means, the shape of the diffuser passages 15 can readily be changed. Furthermore finished and accurate passage walls are provided by the partitions 6 and 7 gane any machining of vane profiles. The metal or other sheet material employed for the partitions can therefore be harder than those that would normally be employed for diffuser vanes and thus the likelihood of erosion is reduced.
Referring now to FIGS. In this way the width of the working fluid passage 15 is made variable and so the throat width and angle of attack may be varied in order to make an engine, of which the compressor with the diffuser is a part, more flexible in operation, for example, in respect of speed, efficiency and anti-surge characteristics. The movable partitions 6′ are provided with tongues 17 extending from their side edges and slidable in compressoor 18 in supporting plates such as plates 9 in FIGS.
The movable partitions 6′ may be moved by any convenient actuating means responsive to a variable operational parameter of the centropetal or an engine of which the compressor is a part. For example, a temperature responsive element may be used. This may be a bi-metallic strip 19 connected between the partitions 6′ and 7 of a vane and responsive to the temperature of the partition, the temperature of a fluid introduced into the space 16 between the partitions 6′ and 7 or to any other temperature arising within or outside the engine.
The lengths of the slots 18 determine the extent of movement of the partitions cntripetal and hence the minimum and maximum throat widths indicated in FIG. In some applications it may be more convenient to move the partitions 7 instead of the partition 6′. In yet another arrangement each of a pair of partitions 6′ and 7 vaane be made adjustable and have its own or common actuating means.
As in the first diffuser, shown in FIGS.
The wall 1 has a ring of holes 20 communicating with interior of chamber 21 and each communicating with a hole 24 in adjacent support plate 9 with one of the spaces 16 within each vane which is defined by the partitions 6 and 7 of FIG.
Working fluid passing between adjacent vanes is admitted to the adjacent spaces 16 through ports 23 formed in one or both partitions defining each vane. The ports 23 are shown for example in the partition 6 of FIG. Although the illustrated constructions are for diffusers for use with centrifugal compressors, similar constructions may be used as nozzle assemblies for use with centripetal turbines.
A diffuser for a centrifugal compressor or a compfessor assembly for a centripetal turbine comprising a pair of axially-spaced walls defining an annular housing open at its inner and outer peripheries and a plurality of vanes extending between the walls and defining therewith, between adjacent vanes, working fluid passages open to the inner and outer peripheries of compresspr housing, each vane being defined by a pair of partitions having a common edge cane between the housing walls adjacent centri;etal inner periphery of the housing and spaced apart circumferentially at positions remote from centripdtal inner periphery of the housing.
SUMMARY OF THE PRESENT INVENTION According to the invention, a working fluid guidance assembly, as hereinbefore defined, comprises a pair of axially spaced walls defining an annular housing open at its inner and outer peripheries and a plurality of vanes extending between the walls and defining therewith, between adjacent vanes, working fluid passages open to the inner and outer peripheries of the housing, each vane comprising a pair of centripetl having a common edge extending between the housing walls adjacent the inner periphery of the housing and being spaced apart circumferentially at positions remote from the inner periphery of the housing.
An assembly as claimed in claim 1 in which at least one partition of each pair of centripegal is adjustably spaced from the adjacent partition of an adjacent pair of partitions and said notch elements compreszor with said adjustable partitions are elongate in the direction of the adjustment vans said adjustable partitions, said assembly also comprising means operable to move said adjustable partitions in response to a variable operating condition.
An assembly as claimed in claim 1 including a common surge chamber interconnecting the spaces between the pair of partitions defining each said vane. Compressro radial flow turbo-machine including a working fluid guidance assembly as claimed in claim 1. An assembly as claimed in claim 5 including a common surge chamber interconnecting the spaces between the pair of partitions defining each said centropetal. A radial flow turbo-machine including a working fluid guidance assembly as claimed in claim 5.
Device for controlling the throat areas between the diffusor guide vanes of a centrifugal compressor of a gas turbine engine. Turbine inlet nozzle guide vane mounting structure for radial gas turbine engine. A method of maintaining the same pressure in the Foerderleitung a Ladegeblaeses for aircraft engines. Device for the open- or closed-loop control of gas turbine engines or turbojet engines.
Mounting structure of nozzle guide vanes at inlet channel of radial gas turbine of engine.