RU149749U1 - TURBOJET ENGINE COMPRESSOR ROTOR ROTOR BLADE - Google Patents

Abstract

1. The blade of the grooved disk of the impeller of the rotor of the low pressure compressor (LPC) of a turbojet engine (turbojet engine), including a flow part, limited by the peripheral contour of the engine housing, characterized in that it contains a feather with a radial axis and a shank with a longitudinal axis and is intended for installation in any of the grooves of the disk of the impeller of the second stage, for which the shank of the blade has a longitudinal axis, coaxial or parallel to the geometric axis of the groove and forming with the axis of the rotor in the projection on the conditional axis плоск plane normal to the radial axis of the blade feather, blade angle α, defined in the range α = (21 ÷ 27) °; a the feather of the blade is made with an axial twist variable with respect to the rotor axis, increasing with radial distance from the axis of the rotor shaft with a pen twist gradient G defined in the projection onto said conditional axial plane defined in the range where α is the projection of the twist angle of the chord of the root section of the blade pen relative to the axis the rotor in the conditional axial plane of the rotor normal to the radial axis of the blade; α is a similar projection of the swirl angle relative to the rotor axis of the most distant peripheral chord of the pen in a plane parallel to the axial one; L is the average radial length of the blade feather; in addition, the blade is equipped with an anti-vibration shelf located in the area of one third of the length from the peripheral end of the blade feather. 2. The blade according to claim 1, characterized in that the feather of the blade is made with lateral edges diverging to the peripheral end with a gradient of increasing the chord G, where L is the length of the peripheral chord connecting the edges of the feather blade; L- long

Description

The utility model relates to the field of aircraft engine manufacturing, namely, to low-pressure compressors of aircraft turbojet engines.

Known axial compressor of the engine containing the stator and the rotor of the drum-disk type, including impellers. Each impeller contains blades consisting of a profiled feather and a shank. The shank of the working blade is made in the form of a shelf with stiffeners and wedge-shaped annular protrusions. On the disks of the impellers, wedge-shaped annular recesses are made, which form an annular dovetail groove for contact with the wedge-shaped annular protrusions at the ends of the shelves of the blades (RU 2269678 C1, publ. 02.10.2006).

Known impeller of an axial compressor of the engine, containing a disk, blades with a shank, means of axial fixation of the blades in the castle connection type "dovetail". On the lateral contact faces of the shanks of the blades, chamfers are made along the chord of a smaller radius of rounding. The axial fixation tool for the blades is made in the form of a split ring and slots for a split ring in the thrust protrusion of the disk and the shank of the blades. The value of the radius of rounding and chamfer selected from the calculation of the ultimate standard strength (RU 2476729 C1, publ. 27.02.2013).

Known profiled compressor blade for the impeller disk having axial, tangential and radial orthogonal axes, containing high and low pressure sides, extending in the radial direction from the shank to the apex and in the axial direction between the front and rear edges, cross sections having corresponding chords and bending lines extending between the leading and trailing edges, and centers of gravity aligned along a pivot axis having a double bend. The low pressure side is curved along the trailing edge near the liner to reduce the separation of the flow on it (RU 2000130594 A, publ. 01.27.2003).

Known compressor blades, including a feather and a shank. The shank of the blade is located horizontally, and the feather is connected to the shank through an intermediate element - the leg. Between the leg and the feather there is a shelf forming the engine flow part (NN Sirotin, AS Novikov, AG Paykin, AN Sirotin. Fundamentals of designing the production and operation of aircraft gas turbine engines and power plants in the CALS system technologies. Book 1. Moscow. Science 2011. p. 257-263).

The disadvantages of the known solutions include the uncertainty in the ratios of the radial and angular parameters of the blades, including parameters expressing the configuration of the shape of the blade pen and the angular installation in the impeller, which reduces the determination of the effectiveness of the interaction of the blade with the flow of the working fluid compressed in the compressor, useful material consumption, manufacturability and work life blades in the compressor.

The problem solved by the utility model consists in developing the impeller blades of the second stage of the rotor shaft of a low-pressure compressor of a turbojet engine with improved geometric configuration, spatial stiffness, power and aerodynamic parameters, providing the possibility of increased supply of compressible air flow to the compressor at all engine operating modes, and also an increase in resource in combination with a decrease in the material consumption of the blade, the complexity of installation in the impeller and simplification of ontoprigodnosti during engine operation.

The problem is solved in that the blade of the rotor of a low-pressure compressor (KND) of a turbojet engine equipped with grooved disk of a rotor of a turbojet engine (TRD), including a flow part limited by a peripheral contour of the engine body, according to a utility model, contains a feather with a radial axis and a shank with a longitudinal axis and is intended for installation in any of the grooves of the disk of the impeller of the second stage, for which the shank of the blade has a longitudinal axis, coaxial or parallel to the geometric axis of the groove and forming with the axis rotor projection on a conditional axial plane normal to the radial axis of the blade feather, blade angle α ₀ , defined in the range α ₀ = (21 ÷ 27) °; and the blade feather is made with a variable axial twist relative to the axis of the rotor, increasing with radial distance from the axis of the rotor shaft with a gradient of twist of the pen G _s.p. defined in projection onto said conditional axial plane, defined in the range

G _s.p. = (α _p -α _k ) / L _cf = (159.2 ÷ 245.8) [deg / m],

where α _to is the projection of the angle of twist of the chord of the root section of the feather of the blade relative to the axis of the rotor in the conditional axial plane of the rotor normal to the radial axis of the blade; α _p - a similar projection of the swirl angle relative to the rotor axis of the most remote peripheral chord of the pen in a plane parallel to the axial one; L _cf - the average radial length of the feather blades; in addition, the blade is equipped with an anti-vibration shelf located in the area of one third of the length from the peripheral end of the blade feather.

In this case, the feather of the scapula can be made with lateral edges diverging to the peripheral end with a gradient of increase in the chord G _у.х. ,

G _u = (L _p.h.- L _c.h. ) / L _cf. = (1.6 ÷ 2.5) · 10 ^-2 [m / m],

where L _p.x is the length of the peripheral chord connecting the edges of the feather blade; L _c.h. - the length of the root chord connecting the edges of the feather blade in the conventional plane parallel to the axial plane of the rotor; L _cf - the average axial length of the feather blades.

The anti-vibration shelf can be oriented along the flow of the working fluid, and each end of the anti-vibration shelf can be mutually supported against the similar end face of an adjacent blade of the impeller facing it.

The blade feather can be made convex-concave with a concave surface in the form of a trough and with a convex surface forming the back of the feather, in addition, the chord connecting the lateral edges of the feather in the root zone forms an angle of installation of the pen with the axis of the rotor in projection onto the conditional plane mentioned above, practically not less than the angle α _{to the} installation of the shank of the blade.

The feather of the blade can be made variable in width and height of the feather thickness, defined in cross section as the difference between the heights of the back and trough relative to the conditional chord connecting the side edges of the feather blade.

The peripheral end face of the feather blade can be made with a variable radius along the width of the end face, repeating with a minimum clearance, providing the possibility of rotation of the wheel, the curvature of the inner surface of the engine duct in the zone of the second stage of the low pressure valve and with a decrease in the radius in the direction of flow of the working fluid.

The technical result achieved by the given set of features consists in the development of a blade of the impeller of the second stage of the rotor shaft of the low pressure turbojet engine with improved geometric configuration, spatial stiffness, power and aerodynamic parameters, which is achieved by the optimal variation of the radial values and thicknesses of the blade feather developed by the utility model, as well as gradients of axial twist varying along the length of the blade and expansion of the pen from the root to the peripheral section of the blade, which ensures ozhnost increased supply of compressed air in the compressor at a relative minimum energy consumption for all modes of engine operation and increase resource in combination with a reduction in material consumption of the blade, the complexity in installation impeller and provides design simplification maintainability developed blade during engine operation.

The essence of the utility model is illustrated by drawings, where:

in FIG. 1 shows a blade of the impeller of the second stage, side view;

in FIG. 2 - the blade of the impeller of the second stage, top view;

in FIG. 3 - feather blades of the impeller of the second stage, a cross section;

in FIG. 4 - a fragment of the disk of the impeller of the second stage, frontal projection.

A turbojet engine includes a housing with a flow part, limited along the peripheral contour of the engine housing. The rotor shaft of the low pressure rotor is made of a stepped drum-disk design, including no more than four disks with working blades.

The blade contains a feather 1 with a radial axis and a shank 2 with a longitudinal axis. The blade is designed for installation in any of the grooves 3 of the disk 4 of the impeller of the second stage. Why shank 2 of the blade has a longitudinal axis, coaxial or parallel to the geometric axis of the groove 3 of the disk 4 and forming with the axis of the rotor in the projection onto the conditional axial plane normal to the radial axis of the feather 1 of the blade, the blade angle α ₀ , defined in the range α ₀ = (17 ÷ 27) °.

The feather 1 of the blade is made with an axial twist variable relative to the axis of the rotor, increasing with a radial distance from the axis of the rotor shaft with the gradient of the twist of the pen G _zp defined in the range of the projected axial plane

G _s.p. = (α _p -α _k ) / L _cf = (159.2 ÷ 245.8) [deg / m],

where α _to - the projection angle of the twist of the chord of the root section of the pen 1 of the blade relative to the axis of the rotor in the conditional axial plane of the rotor normal to the radial axis of the blade; α _p - a similar projection of the swirl angle relative to the rotor axis of the most remote peripheral chord of the pen in a plane parallel to the axial one; L _cf - the average radial length of the feather blades.

The feather 1 of the blade is made with lateral edges 5 diverging to the peripheral end 6 with a gradient of increasing chords G _u.kh. ,

G _u = (L _p.h. -L _k.h. ) / L _cf = (1.6 ÷ 2.5) · 10 ^-2 [m / m], where

L _{P. x} - the length of the peripheral chord connecting the edges 5 of the pen 1 of the scapula; L _c.h. - the length of the root chord connecting the edges 5 of the pen 1 of the scapula in a conditional plane parallel to the axial plane of the rotor; L _cf - the average axial length of the pen 1 of the scapula.

The blade is equipped with an anti-vibration shelf 7 located in the area of one third of the length from the peripheral end 6 of the pen 1 of the blade and oriented along the flow of the working fluid. Each end 8 of the indicated shelf 7 is made with the possibility of mutual support on facing a similar end face of an adjacent blade of the impeller.

The feather 1 of the blade is convex-concave, with a concave surface in the form of a trough 9, endowed with a discharge function, and with a convex surface forming the backrest 10 of feather 1 with the function of diluting the pressure and suction of the flow of the working fluid during rotation of the impeller. The chord connecting the lateral edges 5 of the pen 1 in the root zone 11 forms, with the axis of the rotor in the projection onto the said conventional plane, the angle of installation of the pen 1, practically no less than the angle α _{to the} installation of the shank 2 of the blade.

Feather 1 of the blade is made variable in width and height of feather 1 with a thickness defined in cross section as the difference in height of the backrest 10 and trough 9 relative to the conditional chord 12 connecting the side edges 5 of the feather 1 of the blade.

The peripheral end face 6 of the pen 2 of the blade is made with a variable radius along the width of the end face, repeating with a minimum clearance providing the possibility of rotation of the wheel, the curvature of the inner surface of the engine duct in the area of the second stage of the low pressure valve and with a decrease in radius in the direction of flow of the working fluid.

The work is as follows.

During the operation of a turbojet engine, the rotor blades of a rotating impeller of the indicated KND stage interact with the working fluid. At the same time, a zone of increased pressure is created on a concave surface in the form of a trough 9 of feather 1 of each blade, and a zone of reduced pressure is created on a convex surface forming the backrest 10 of feather 1. Due to what there is a directed flow of the working fluid. Rotating rotor rotor blades transmit energy to the working fluid, directing the compressible air flow to the stator blades of the second stage, and after alignment in the latter, the flow enters the subsequent stages of the low pressure switch.

Claims (6)

1. The blade of the grooved disk of the impeller of the rotor of the low pressure compressor (LPC) of a turbojet engine (turbojet engine), including a flow part, limited by the peripheral contour of the engine housing, characterized in that it contains a feather with a radial axis and a shank with a longitudinal axis and is intended for installation in any of the grooves of the disk of the impeller of the second stage, for which the shank of the blade has a longitudinal axis, coaxial or parallel to the geometric axis of the groove and forming with the axis of the rotor in the projection on the conditional axis плоск plane normal to the radial axis of the blade feather, blade angle α ₀ , defined in the range α ₀ = (21 ÷ 27) °; a feather blade is made with a variable axial twist relative to the axis of the rotor, increasing with a radial distance from the axis of the rotor shaft with a gradient of twist of the pen G _s.p. defined in projection onto said conditional axial plane, defined in the range

where α _to is the projection of the angle of twist of the chord of the root section of the feather of the blade relative to the axis of the rotor in the conditional axial plane of the rotor normal to the radial axis of the blade; α _p - a similar projection of the swirl angle relative to the rotor axis of the most remote peripheral chord of the pen in a plane parallel to the axial one; L _cp is the average radial length of the blade feather; in addition, the blade is equipped with an anti-vibration shelf located in the region of one third of the length from the peripheral end of the blade feather. 2. The blade according to claim 1, characterized in that the feather of the blade is made with lateral edges diverging to the peripheral end with a gradient of increasing chord G _yx ,

where L _p.x - the length of the peripheral chord connecting the edges of the feather blades; L _c.x. - the length of the root chord connecting the edges of the feather blade in the conventional plane parallel to the axial plane of the rotor; L _cp - the average axial length of the feather blades. 3. The blade according to claim 1, characterized in that the anti-vibration shelf is oriented along the flow of the working fluid, and each end of the anti-vibration shelf is made with the possibility of mutual support against the similar end of the adjacent blade of the impeller facing it. 4. The blade according to claim 1, characterized in that the feather of the blade is convex-concave with a concave surface in the form of a trough and with a convex surface forming the back of the feather, in addition, the chord connecting the lateral edges of the feather in the root zone forms with the axis of the rotor in the projection onto the mentioned conditional plane, the angle of installation of the pen is practically not less than the angle α _{to the} installation of the shank of the blade. 5. The blade according to claim 1, characterized in that the feather of the blade is made variable in width and height of the feather with a thickness defined in cross section as the difference in height of the back and trough relative to the conditional chord connecting the lateral edges of the blade feather. 6. The blade according to claim 1, characterized in that the peripheral end face of the feather blade is made with a variable radius along the width of the end face, repeating with a minimum clearance that allows the wheel to rotate, the curvature of the inner surface of the engine duct in the second stage of the low pressure valve and with a decrease in radius direction of flow of the working fluid.

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