Turbine

Patent metadata

Field	Value
Publication number	US-10731467-B2
Application number	US-201415329959-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2014
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A turbine includes a housing including an inlet, an outlet, and a shroud section having a shroud surface extending between the inlet and the outlet; and a turbine impeller housed in the housing and including a hub and a plurality of blades disposed on an outer peripheral surface of the hub, each of the blades having a side edge extending along the shroud surface. The side edge of each of the blades has a side-edge upstream portion disposed on a side of the inlet, and a side-edge downstream portion disposed on a side of the outlet. The shroud surface has a shroud upstream portion disposed on the side of the inlet and extending along the side-edge upstream portion, and a shroud downstream portion disposed on the side of the outlet and extending along the side-edge downstream portion. The shroud upstream portion has a meridional cross-sectional shape whose inclination angle (θ 1 ) with respect to an axis (L) of the hub at the side of the inlet is smaller than in a case where the shroud upstream portion has a meridional cross-sectional shape of an arc shape and the shroud downstream portion has a meridional cross-sectional shape of a linear shape along a direction of the axis of the hub.

First claim

The invention claimed is:

1. A turbine, comprising:
a housing including an inlet, an outlet, and a shroud section having a shroud surface extending between the inlet and the outlet; and
a turbine impeller housed in the housing and including a hub and a plurality of blades disposed on an outer peripheral surface of the hub, each of the blades having a side edge extending along the shroud surface,
wherein the side edge of each of the blades has
a side-edge upstream portion disposed on a side of the inlet, and
a side-edge downstream portion disposed on a side of the outlet,

wherein the shroud surface has
a shroud upstream portion disposed on the side of the inlet and extending along the side-edge upstream portions of the blades, and
a shroud downstream portion disposed on the side of the outlet and extending along the side-edge downstream portion, and

wherein the shroud upstream portion has a meridional cross-sectional shape having a curvature radius R defined by following expression 1:

R
≧

(

R
⁢

⁢
1

-

R
⁢

⁢
2
⁢
t

)

2

+

Ls
2

2
⁢

(

R
⁢

⁢
1

-

R
⁢

⁢
2
⁢
t

)

where R 1 is a distance in a radial direction from an axis of the hub to the inlet, R 2 t is a distance in the radial direction from the axis of the hub to the outlet, and Ls is a length of the shroud surface in a direction of the axis of the hub, and
wherein the shroud downstream portion has a meridional cross-sectional of an arc shape having a curvature radius R defined by following expression 2:

R
=

(

R
⁢

⁢
1

-

R
⁢

⁢
2
⁢
t

)

2

+

Ls
2

2
⁢

(

R
⁢

⁢
1

-

R
⁢

⁢
2
⁢
t

)

.

2. The turbine according to claim 1 ,
wherein a ratio Ls/D 1 of the length Ls to an inner diameter D 1 is greater than 0.16, provided that D 1 is an inner diameter of the shroud at the inlet.

3. The turbine according to claim 1 ,
wherein a ratio of a distance R 2 t to a distance R 1 is not more than 0.95, provided that R 1 is a distance in a radial direction from the axis of the hub to the inlet, and R 2 t is a distance in the radial direction from the axis of the hub to the outlet.

Assignees

• Mitsubishi Heavy Ind Engine & Turbocharger Ltd

Inventors

• Yoshida Toyotaka
• Yokoyama Takao

Classifications

• F01D5/14

  Form or construction (selecting particular materials, measures against erosion or corrosion F01D5/28) · CPC title

• F01D5/04 Primary

  for radial-flow machines or engines · CPC title

• F05D2220/40

  in turbochargers · CPC title

• F04D29/526

  Details of the casing section radially opposing blade tips (ducts F04D29/545) · CPC title

• F01D11/08

  for sealing space between rotor blade tips and stator (specially-shaped blade tips therefor F01D5/20) · CPC title