Transfer tube system routing through limited space for gas turbine engine bleed system

1 . A transfer tube system for connecting between a compressor and a bleed unit of a turbomachine defined about a longitudinal axis that extends in a longitudinal direction, the transfer tube system comprising:

a valve assembly with an inlet, the valve assembly disposed to control gas flow from the compressor through a bleed system, the valve assembly disposed outside the turbomachine;

a port in fluid communication with the compressor, the port disposed in the turbomachine at the compressor;

a strut having an interior space, the strut extending in a radial direction, at least partly, between the compressor and the valve assembly, the strut extending in the longitudinal direction across the compressor and radially outside from the compressor; and

a conduit connected between the port and the inlet, the conduit configured to convey gas between the compressor and the valve assembly,

wherein the conduit includes a first connection coupled with the port and a second connection coupled with the inlet,

wherein the conduit is curved so that the first connection and the second connection are not in line with one another in the radial direction and are at different locations along the longitudinal direction,

wherein the conduit passes through the interior space of the strut,

wherein the conduit includes a first bellows disposed in the interior space of the strut and a second bellows disposed in the interior space of the strut,

wherein, between the first bellows and the second bellows, the conduit has a central section with a non-circular shaped cross section in the interior space of the strut.

2 . The transfer tube system of claim 1 , wherein the conduit includes a radial bellows disposed adjacent to the inlet of the valve assembly and configured to adapt to movement of the central section relative to the inlet, wherein the radial bellows is disposed at about ninety degrees relative to the first bellows and is configured for radial directed deformation for movement perpendicular to a centerline of the conduit.

3 . The transfer tube system of claim 1 , wherein the conduit includes an internal baffle extending longitudinally in the central section, wherein the internal baffle is configured to provide structural support to the conduit, wherein the central section has an oval shape with flat sides and the internal baffle extends along the central section in its entirety and the internal baffle extends between and contacts the flat sides of the oval shape.

4 . The transfer tube system of claim 1 , further comprising a second conduit, wherein the second conduit extends through the interior space from a second port of the compressor to a second inlet of the valve assembly, wherein the second port is disposed at a point of the compressor that is at a different pressure as compared to the port.

5 . The transfer tube system of claim 1 , wherein:

the compressor is disposed in a core of the turbomachine,

a bypass duct is defined around the core;

the valve assembly is disposed on an outer wall of the bypass duct; and

the strut extends through the bypass duct from the core to the outer wall.

6 . The transfer tube system of claim 1 , wherein the conduit includes a cylindrical section disposed adjacent to the port, the cylindrical section having a circular cross section and including a third bellows, the third bellows disposed at about ninety degrees relative to the first bellows, the third bellows having a circular cross section, the conduit including a diffusion section that transitions the circular cross section to the non-circular cross section, wherein the diffusion section is disposed between the first bellows and the third bellows, wherein the non-circular cross section is provided at the central section and at both the first bellows and the second bellows.

7 . The transfer tube system of claim 6 , wherein the non-circular cross section has a flow area at least as large as the circular cross section, wherein the non-circular shaped cross section of the central section is constant in shape from the first bellows to the second bellows.

8 . The transfer tube system of claim 1 , wherein the central section has an axial dimension that is twice a magnitude of a lateral dimension of the central section.

9 . The transfer tube system of claim 1 , wherein the first bellows and the second bellows each have a first wall thickness that is thinner than a second wall thickness of the central section.

10 . The transfer tube system of claim 1 , wherein:

the strut extends, in the longitudinal direction, from a front frame assembly of the turbomachine,

the strut includes a leading end that is flat and abuts against an element of the front frame assembly and both the strut and the element have a lateral thickness that is the same,

the strut has a pair of side walls that are mirror images of one another and that extend from the leading end to a trailing end of the strut where the side walls join together,

the side walls are parallel to one another for a first straight section of the strut adjacent the front frame assembly,

the side walls diverge from one another downstream from the first straight section forming a diffusion section,

downstream from the diffusion section the strut includes a second straight section where the side walls are parallel to one another and where the side walls are spaced from one another defining, at least in part, the interior space,

downstream from the second straight section, the side walls converge toward one another forming a converging section,

the side walls join together at the trailing end in a curved tail,

the conduit has an oval shape at the central section with a first dimension in the longitudinal direction and a second dimension in a lateral direction perpendicular to the longitudinal direction,

the first dimension is about twice the second dimension in size so that the conduit is configured to enable minimizing a width of the strut,

the conduit has a spine configured as a smooth curve connecting an inlet vector at the port and an exit vector at the inlet, wherein the spine is substantially S-shaped, wherein the conduit is centered on the spine and the spine is disposed within the interior space in the second straight section.

11 . A transfer tube system for connecting between a compressor and a bleed unit of a turbomachine defined about a longitudinal axis that extends in a longitudinal direction, the transfer tube system comprising:

a valve assembly with a first inlet and a second inlet, the valve assembly disposed to control gas flow from the compressor through a bleed system, the valve assembly disposed outside the turbomachine;

a first port in fluid communication with the compressor, the first port disposed in the turbomachine at the compressor;

a second port in fluid communication with the compressor, the second port disposed in the turbomachine at the compressor;

a strut having an interior space, the strut extending in a radial direction, at least partly, between the compressor and the valve assembly, the strut extending in the longitudinal direction across the compressor and radially outside from the compressor;

a first conduit configured as a first bleed tube connected between the first port and the first inlet, the first conduit configured to convey a first gas flow between the compressor and the valve assembly; and

a second conduit configured as a second bleed tube connected between the second port and the second inlet, the second conduit configured to convey a second gas flow between the compressor and the valve assembly,

wherein both the first conduit and the second conduit extend through the interior space of the strut,

wherein the first conduit includes a first pair of bellows disposed in the interior space of the strut and the second conduit includes a second pair of bellows disposed in the interior space of the strut,

wherein the first conduit includes a first connection coupled with the first port and a second connection coupled with the first inlet,

wherein the second conduit includes a third connection coupled with the second port and a fourth connection coupled with the second inlet,

wherein each of the first conduit and the second conduit is curved and each extends from a respective inlet flange at the compressor to a respective exit flange at the valve assembly, each respective exit flange disposed at a different angle as compared to its respective inlet flange,

wherein, between the first pair of bellows, the first conduit has a first central section with a first non-circular shaped cross section in the interior space of the strut,

wherein, between the second pair of bellows, the second conduit has a second central section with a second non-circular shaped cross section in the interior space of the strut.

12 . The transfer tube system of claim 11 , wherein the first conduit includes a radial bellows disposed adjacent to the first inlet and configured to adapt to movement of the first central section relative to the first inlet, wherein the radial bellows is disposed at about ninety degrees relative to the first bellows and is configured for radial directed deformation for movement perpendicular to a centerline of the first conduit.

13 . The transfer tube system of claim 11 , wherein the first conduit includes a first internal baffle extending longitudinally in the first central section, the first internal baffle configured to provide structural support to the first conduit, and wherein the second conduit includes a second internal baffle extending longitudinally in the second central section, the second internal baffle configured to provide structural support to the second conduit, wherein the first central section has an oval shape with flat sides and the first internal baffle extends along the first central section in its entirety and the first internal baffle extends between and contacts the flat sides of the oval shape.

14 . The transfer tube system of claim 11 , wherein the second port is disposed at a point of the compressor that is at a lower pressure as compared to the first port.

15 . The transfer tube system of claim 11 , wherein:

the compressor is disposed in a core of the turbomachine,

a bypass duct is defined around the core;

the valve assembly is disposed on an outer wall of the bypass duct and comprises the bleed unit with a high pressure shutoff valve, and a pressure regulating valve; and

the strut extends through the bypass duct from the core to the outer wall.

16 . The transfer tube system of claim 11 , wherein the first conduit includes a cylindrical section disposed adjacent to the first port, the cylindrical section having a circular cross section and including a third bellows, the third bellows disposed at about ninety degrees relative to the first bellows, the third bellows having a circular cross section, wherein the first conduit includes a diffusion section that transitions the circular cross section to the first non-circular shaped cross section, wherein the diffusion section is disposed between the first bellows and the third bellows, wherein the first non-circular shaped cross section is provided at the first central section and at each bellows in the first pair of bellows.

17 . The transfer tube system of claim 16 , wherein the first non-circular shaped cross section has a flow area at least as large as the circular cross section, wherein the first non-circular shaped cross section of the central section is constant in shape from the first bellows to the second bellows.

18 . The transfer tube system of claim 11 , wherein the first central section has an axial dimension that is twice a magnitude of a lateral dimension of the first central section.

19 . The transfer tube system of claim 11 , wherein:

the strut extends, in the longitudinal direction, from a front frame assembly of the turbomachine,

the strut includes a leading end that is flat and abuts against an element of the front frame assembly and both the strut and the element have a lateral thickness that is the same,

the strut has a pair of side walls that are mirror images of one another and that extend from the leading end to a trailing end of the strut where the side walls join together,

the side walls are parallel to one another for a first straight section of the strut adjacent the front frame assembly,

the side walls diverge from one another downstream from the first straight section forming a diffusion section,

downstream from the diffusion section the strut includes a second straight section where the side walls are parallel to one another and where the side walls are spaced from one another defining, at least in part, the interior space,

downstream from the second straight section, the side walls converge toward one another forming a converging section,

the side walls join together at the trailing end in a curved tail,

the first conduit has an oval shape at the central section with a first dimension in the longitudinal direction and a second dimension in a lateral direction perpendicular to the longitudinal direction,

the first dimension is about twice the second dimension in size so that the first conduit is configured to enable minimizing a width of the strut,

the first conduit has a spine configured as a smooth curve connecting an inlet vector at the first port and an exit vector at the first inlet, wherein the spine is substantially S-shaped, wherein the first conduit is centered on the spine and the spine is disposed within the interior space in the second straight section.

20 . A transfer tube system for connecting between a compressor and a bleed unit of a turbomachine defined about a longitudinal axis that extends in a longitudinal direction, the transfer tube system comprising:

a valve assembly in the bleed unit that has a first inlet and a second inlet, the valve assembly disposed to control bleed air flow from the compressor through a bleed system, the valve assembly disposed outside the turbomachine;

a first port in fluid communication with the compressor and configured to receive a first pressure, the first port disposed in the turbomachine at the compressor;

a second port in fluid communication with the compressor and configured to receive a second pressure, wherein the second pressure is different than the first pressure, the second port disposed in the turbomachine at the compressor;

a strut having an interior space, the strut extending in a radial direction, at least partly, between the compressor and the valve assembly and through a bypass duct of the turbomachine, the strut extending in the longitudinal direction across the compressor and radially outside from the compressor;

a first conduit configured as a first bleed tube connected between the first port and the first inlet, the first conduit configured to convey a first flow of bleed air between the compressor and the valve assembly; and

a second conduit configured as a second bleed tube connected between the second port and the second inlet, the second conduit configured to convey a second flow of bleed air between the compressor and the valve assembly,

wherein both the first conduit and the second conduit extend through the interior space of the strut,

wherein the first conduit includes a first connection coupled with the first port and a second connection coupled with the first inlet,

wherein the second conduit includes a third connection coupled with the second port and a fourth connection coupled with the second inlet,

wherein the first conduit includes a first pair of bellows disposed in the interior space of the strut and the second conduit includes a second pair of bellows disposed in the interior space of the strut,

wherein, between the first pair of bellows, the first conduit has a first central section with a first non-circular shaped cross section in the interior space of the strut,

wherein, between the second pair of bellows, the second conduit has a second central section with a second non-circular shaped cross section in the interior space of the strut,

wherein each of the first conduit and the second conduit is curved and each extends from a respective inlet flange at the compressor to a respective exit flange at the valve assembly, each respective exit flange disposed at a different angle as compared to its respective inlet flange,

wherein the first conduit has a spine comprising a smooth curve connecting an inlet vector at the first port and an exit vector at the first inlet, wherein the spine is substantially S-shaped.