Turbocharger, nozzle vane for turbocharger, and turbine

Patent metadata

Field	Value
Publication number	US-10851797-B2
Application number	US-201616309669-A
Country	US
Kind code	B2
Filing date	Dec 21, 2016
Priority date	Dec 21, 2016
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

A turbocharger includes: a turbine wheel; a hub-side wall surface and a shroud-side wall surface which face each other and which together form a flow path for exhaust gas to flow into the turbine wheel; and a nozzle vane which has a shroud-side end surface facing the shroud-side wall surface and a hub-side end surface facing the hub-side wall surface and which is rotatably disposed in the flow path. The nozzle vane has a pressure surface which is, at least on a shroud side, oblique toward a downstream side of the exhaust gas with a distance in a vane height direction from the shroud-side end surface.

First claim

The invention claimed is:

1. A turbocharger comprising:
a turbine wheel;
a hub-side wall surface and a shroud-side wall surface which face each other and which together form a flow path for exhaust gas to flow into the turbine wheel; and
a nozzle vane which has a shroud-side end surface facing the shroud-side wall surface and a hub-side end surface facing the hub-side wall surface and which is rotatably disposed in the flow path,
wherein the nozzle vane has a pressure surface which is, at least on a shroud side, oblique toward a downstream side of the exhaust gas with a distance in a vane height direction from the shroud-side end surface, and
wherein an x-axis is taken along a normal direction of a camber line of the nozzle vane from the pressure surface toward a suction surface of the nozzle vane, and a y-axis is taken along the vane height direction from the hub-side end surface toward the shroud-side end surface, coordinates (x s , y s ) of the suction surface on a trailing edge side of the nozzle vane and coordinates (x p , y p ) of the pressure surface on a leading edge side of the nozzle vane satisfy the following relational expression within a positional range in the vane height direction including the shroud-side end surface:

0
<

dy
s

dx

s
⁢

<

dy
p

dx
p

.

2. The turbocharger according to claim 1 ,
wherein the nozzle vane has:
a first end surface which is one of the shroud-side end surface or the hub-side end surface; and
a second end surface which is the other of the shroud-side end surface or the hub-side end surface,

wherein the nozzle vane is rotatably supported on one of the hub-side wall surface or the shroud-side wall surface which faces the second end surface, and
wherein the suction surface on a trailing edge side of the nozzle vane has, in a cross-section including a normal direction of a camber line of the nozzle vane and the vane height direction, a concave shape from a position of the first end surface to a middle position between the first end surface and the second end surface.

3. The turbocharger according to claim 1 ,
wherein the nozzle vane has:
a first end surface which is one of the shroud-side end surface or the hub-side end surface; and
a second end surface which is the other of the shroud-side end surface or the hub-side end surface,

wherein the nozzle vane is rotatably supported on one of the hub-side wall surface or the shroud-side wall surface which faces the second end surface, and
wherein the pressure surface on a leading edge side of the nozzle vane has, in a cross-section including a normal direction of a camber line of the nozzle vane and the vane height direction, a concave shape from a position of the first end surface to a middle position between the first end surface and the second end surface.

4. The turbocharger according to claim 1 ,
wherein the nozzle vane has:
a first end surface which is one of the shroud-side end surface or the hub-side end surface; and
a second end surface which is the other of the shroud-side end surface or the hub-side end surface,

wherein the nozzle vane is rotatably supported on one of the hub-side wall surface or the shroud-side wall surface which faces the second end surface, and
wherein a throat formed between adjacent two of the nozzle vanes has a narrower throat width at a position of the first end surface than a throat width at a middle position between the first end surface and the second end surface.

5. The turbocharger according to claim 4 , wherein the throat width monotonically increases with an increase in a distance from the position of the first end surface toward the middle position.

6. A nozzle vane for a turbocharger, comprising:
a vane body having a shroud-side end surface and a hub-side end surface; and
a rotatable shaft to rotate the vane body,
wherein the vane body has a pressure surface which is, at least within a positional range in a vane height direction including the shroud-side end surface, oblique toward a side of a pressure surface of the vane body with a distance in the vane height direction from the shroud-side end surface, and
wherein an x-axis is taken along a normal direction of a camber line of the vane body from the pressure surface toward a suction surface of the vane body, and a y-axis is taken along the vane height direction from the hub-side end surface toward the shroud-side end surface, coordinates (x s , y s ) of the suction surface on a trailing edge side of the vane body and coordinates (x p , y p ) of the pressure surface on a leading edge side of the vane body satisfy the following relational expression within a positional range in the vane height direction including the shroud-side end surface:

0
<

dy
s

dx

s
⁢

<

dy
p

dx
p

.

7. The nozzle vane for a turbocharger according to claim 6 ,
wherein the vane body has:
a first end surface which is one of the shroud-side end surface or the hub-side end surface; and
a second end surface which is the other of the shroud-side end surface or the hub-side end surface,

wherein the rotatable shaft is disposed on the second end surface, and
wherein the suction surface on a trailing edge side of the vane body has, in a cross-section including a normal direction of a camber line of the vane body and the vane height direction, a concave shape from a position of the first end surface to a middle position between the first end surface and the second end surface.

8. The nozzle vane for a turbocharger according to claim 6 ,
wherein the vane body has:
a first end surface which is one of the shroud-side end surface or the hub-side end surface; and
a second end surface which is the other of the shroud-side end surface or the hub-side end surface,

wherein the rotatable shaft is disposed on the second end surface, and
wherein the pressure surface on a leading edge side of the vane body has, in a cross-section including a normal direction of a camber line of the vane body and the vane height direction, a concave shape from a position of the first end surface to a middle position between the first end surface and the second end surface.

9. A turbine, comprising:
a nozzle vane according to claim 6 ; and
a turbine wheel disposed on a downstream side of the nozzle vane.

Assignees

• Mitsubishi Heavy Ind Engine & Turbocharger Ltd

Inventors

• Gupta Bipin
• Yoshida Toyotaka
• Dammoto Yosuke
• Akiyama Yoji

Classifications

• F02B37/24 Primary

  by using pumps or turbines with adjustable guide vanes · CPC title

• F05D2220/40

  in turbochargers · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F05D2240/124

  related to the suction side of a stator vane · CPC title

• F01D17/165

  for radial flow, i.e. the vanes turning around axes which are essentially parallel to the rotor centre line (F01D17/167 takes precedence) · CPC title