JPH10299403A - Variable capacity radial turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide constant turbine output from a lower flow rate area to a higher flow rate area, by arranging a shielding member which shields an inflow passage between fixed nozzles which are inflow passages to a turbine moving blade and vary turbine capacity by varying the shield amount, and by driving and controlling it. SOLUTION: Both ends along the width of each fixed nozzle 1 are in contact with inside of a scroll 2, a notch 1a is arranged at one end along the width of each fixed nozzle 1, and a throat wall 5 which shields an inflow passage into the turbine moving blade 3 and can vary the amount of shield of the inflow passage into the turbine moving blade 3 is arranged on the surface of the notch 1a. The throat wall 5 can move along the width of the fixed nozzle 1 by a driving device 7 via a coupling rod 6 penetrating through the scroll 2. When a flow rate of gas is low, the throat wall 5 is placed at a shield position contacting with the bottom of the notch 1a, moved to the right by the driving device 7 with increasing flow rate of gas, and controlled such that the inflow passage into the turbine moving blade 3 becomes wide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable displacement radial turbine used for small gas turbines, expanders, turbochargers and the like.

[0002]

2. Description of the Related Art A conventional radial turbine having a fixed nozzle is shown in FIGS. The gas that has entered from the scroll inlet portion 02a of the scroll 02 passes through the inner passage 02b of the scroll and is guided to the plurality of fixed nozzles 01 provided at intervals from each other over the entire periphery of the inner portion of the inner passage 02b of the scroll. Fixed nozzle 01
After being accelerated by the throat 01a, which is an inflow path to the turbine blade 03 formed by the above, the turbine rotor 04 flows into the rotatable turbine blade 03 provided inside the plurality of fixed nozzles 01, and the turbine rotor 04 Rotate to do work.

[0003]

FIG. 9 and FIG. 10 show a conventional radial turbine having a fixed nozzle.
As shown in the figure, the shape of the nozzle, the mounting angle and the throat area are shapes designed to work most efficiently at the rated flow rate of the used turbocharger turbine and the like. In a small flow rate region, since the throat area of the fixed nozzle is large, sufficient gas acceleration cannot be obtained in the throat portion, causing an extreme decrease in efficiency and no turbine output. If the nozzle shape, mounting angle and throat area are set in accordance with the small flow rate range at the time of starting the turbocharger, the supercharging pressure becomes too high at the rated flow rate.

In order to improve the above situation, there is a variable capacity (VG) turbine (variable geometry turbine) and the like, which is not a fixed nozzle but is indicated by a dotted line and an arrow in FIG. As described above, there is a device in which the throat area is changed by adjusting the throat width by rotating the nozzle to accelerate the gas with the nozzle from a small flow region to a large flow region and obtain a stable turbine output. The structure of this variable displacement turbine is complicated, such as having a link mechanism for rotating all nozzles, and has problems in terms of cost and durability.

The present invention solves the above-mentioned problems in the prior art, and provides a variable displacement radial turbine configured to obtain a stable turbine output from a small flow rate range to a large flow rate range by a simple mechanism. That is the task.

[0006]

In order to solve the above-mentioned problems, the present invention provides a turbine blade rotatably installed,
In a radial turbine having a plurality of fixed nozzles forming an inflow path of a fluid such as a gas for rotating the turbine blade to the turbine blade, an inflow path between the fixed nozzles serving as an inflow path to the turbine blade. Variable-capacity radial having a shielding member for varying the turbine capacity by variably setting a shielding amount of the inflow passage, and a driving unit for variably driving the shielding amount of the shielding member. Provide a wind turbine.

[0007] In the variable displacement radial turbine according to the present invention, the inflow passage between the fixed nozzles, which serves as the inflow passage to the turbine rotor blade, is shielded by a predetermined amount by a shielding member, thereby making the turbine capacity variable and controlling the fluid flow rate. Regardless of the change, the fluid can flow into the turbine blade at a predetermined flow velocity and inflow angle, and the turbine efficiency does not decrease.

Further, in the variable displacement radial turbine according to the present invention, it is sufficient to provide a driving means for only displacing the shielding member so as to change the shielding amount, and it is complicated to rotate the nozzle as in the conventional one. Since no link mechanism is required, the structure is simple, the cost is low, and the durability is excellent.

Further, the present invention has been made in order to solve the above-mentioned problems.
In a radial turbine having a turbine rotor blade rotatably installed and a plurality of fixed nozzles forming an inflow path of a fluid such as gas for rotating the turbine rotor blade to the turbine rotor blade, An annular throat wall having a shape overlapping with the fixed nozzle of the throat portion and movably arranged in the rotational axis direction so as to change the area of the throat portion, and variably driving the rotational axial position of the annular throat wall. A variable displacement radial turbine having driving means.

In the variable displacement radial turbine configured as described above, the inflow path area between the fixed nozzles is variably changed only by changing the position of the annular throat wall in the rotation axis direction by the driving means described above, and the turbine rotor blades are changed. Fluid can flow at a predetermined flow velocity and an inflow angle regardless of a change in the fluid flow rate, and the turbine efficiency does not decrease.

Further, in order to solve the above-mentioned problems, the present invention forms a turbine rotor blade rotatably installed and an inflow path of a fluid such as gas for rotating the turbine rotor blade into the turbine rotor blade. In the radial turbine having a plurality of fixed nozzles, a notch provided at one end of each of the fixed nozzles is fitted to each of the notches to shield an inflow path to a turbine rotor blade, and Provided is a variable displacement radial turbine having a configuration including a shielding member that varies a turbine capacity by variably setting a shielding amount of an inflow path and a driving unit that variably drives the shielding amount of the shielding member. .

In the variable displacement radial turbine having this configuration, the shielding member fits into the notch provided at one end of the fixed nozzle, and the fluid such as gas flows to the turbine blade formed by the plurality of fixed nozzles. The area of the inflow path is changed according to a change in the flow rate of a fluid such as gas by a shielding member that shields the inflow path and varies the amount of shielding of the inflow path, and enlarges or reduces the area.

Thus, even if the flow rate of the fluid such as gas changes, the fluid such as gas can flow into the turbine blade at a substantially constant flow velocity and an inflow angle. High turbine efficiency can be obtained even when the flow rate changes from the flow rate range to the large flow rate range.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A variable displacement radial turbine according to the present invention will be specifically described below based on the embodiment shown in FIGS.

(First Embodiment) First, a variable displacement radial turbine according to a first embodiment of the present invention will be described with reference to FIGS. The fixed nozzle 1, the scroll 2, the scroll passage 2b, the turbine rotor blades 3, and the turbine rotor 4 in the variable displacement radial turbine according to the first embodiment are different from the conventional one shown in FIGS. Since it does not exist, the description is omitted.

Both ends of each fixed nozzle 1 in the width direction (left-right direction in FIG. 1) are in contact with the inner surface of the scroll 2 as shown in FIG. Behind the part near the wing 3 (on the downstream side of the gas flow)
Is provided with a notch 1a toward the other end. The fixed nozzle 1 is fitted to the surface of the notch 1a to be in contact with the bottom surface of the notch 1a to cut off the inflow path to the turbine blade 3 and to be separated from the surface of the notch 1a and An annular throat wall 5 is provided as a shielding member that makes it possible to change the amount of shielding of the inflow path to the inflow path 3.

The throat wall 5 is connected to a connecting rod 6 penetrating the scroll 2, and the connecting rod 6 is fixed by a driving device 7 provided outside the scroll 2.
In the width direction. The connecting rod 6
An appropriate number of the driving devices 7 are provided at intervals in the circumferential direction of the annular throat wall 5.

The drive unit 7 fits the throat wall 5 through the connecting rod 6 to the surface of the notch 1a shown by a solid line in FIG. Can be moved to a position where the amount of shielding of the inflow path to the turbine bucket 3 can be made variable away from the bottom surface of the notch 1a as appropriate.

In the first embodiment configured as described above, when the flow rate of the gas is small, the throat wall 5 is located at the shielding position in contact with the bottom surface of the notch 1a shown by a solid line in FIG. The inflow path to the turbine blade 3 formed between the fixed nozzles 1 is minimized. When the gas flow rate increases, the throat wall 5 moves rightward in FIG. 1 away from the bottom surface of the notch 1 a by the driving device 7 via the connecting rod 6, and moves to the right in FIG. Enlarge the inflow channel to

As described above, in the first embodiment, the size of the inflow path to the turbine blade 3 is adjusted by the simple device as described above according to the gas flow rate, and the turbine capacity is made variable. Thus, the gas flows into the turbine blade 3 with a substantially constant flow velocity and an inflow angle even if the flow rate changes. Therefore, high turbine efficiency can be obtained from a small gas flow rate range to a large gas flow range.

The notch 1a in the first embodiment
Is located at an appropriate position in the width direction of the fixed nozzle 1 in accordance with the minimum value of the gas flow rate.
a may be provided over the entire length of the fixed nozzle 1 in the width direction.

(Second Embodiment) Next, a variable displacement radial turbine according to a second embodiment shown in FIGS. 3 and 4 will be described. 3 and 4, reference numeral 15 denotes an annular throat wall, which is formed in the throat 01a portion of the fixed nozzle 1 by cutting a portion overlapping the fixed nozzle. The annular throat wall 15 is displaced in the rotational axis direction by the driving device 7 via the connecting rod 6 while being fitted between the fixed nozzles, and partially blocks the inflow path between the adjacent fixed nozzles 1. It is configured as follows.

The fixed nozzle 1 is not provided with a notch. The other configuration is substantially the same as the configuration of the variable displacement radial turbine according to the first embodiment shown in FIGS.

In the variable displacement radial turbine according to the second embodiment having the above-described configuration, gas flowing into the scroll 2 from the scroll inlet of the radial turbine passes through the scroll internal passage 2b, is guided to the fixed nozzle 1, and is guided to the throat. It is accelerated at 01a. The annular throat wall 15 connected to the driving device 7 by the connecting rod 6 moves inside the throat 01a of the fixed nozzle 1 in the rotation axis direction by the operation of the driving device 7, and changes the height of the nozzle throat.

Since the throat area of the fixed nozzle 1 is determined by “throat width × nozzle height”, when the flow rate of the inflow gas is large, the annular throat wall 15 is separated from the nozzle end face 1b, so that the nozzle height increases and the throat area increases. The area is enlarged.

Conversely, when the flow rate is small, the annular throat wall 15
Is closer to the nozzle end face 1b, the nozzle height is reduced and the throat area is reduced, and even when the gas flow rate varies over a wide range, the inflow speed and the inflow angle to the turbine blades are kept almost constant, and the high turbine Efficiency is obtained.

(Third Embodiment) Next, a variable displacement radial turbine according to a third embodiment shown in FIG. 5 will be described. In FIG. 5, reference numeral 8 denotes an annular throat wall. The annular throat wall 8 is arranged on the inlet side of the fixed nozzle 1 and is connected to a driving device 7 via a connecting rod 6 so as to be movable in the direction of the rotation axis. It has become.

The annular throat wall 8 is connected to the driving device 7 by using two or more connecting rods 6. Scroll 2
Are divided into two parts for the annular throat wall 8, but are connected by the scroll connecting rod 2c. Other configurations are substantially the same as the configuration of the variable displacement radial turbine according to the first embodiment.

In the variable displacement radial turbine of the third embodiment having the above configuration, the annular throat wall 8 connected to the driving device 7 by the connecting rod 6 is moved in the direction of the rotation axis by the driving device 7. Thus, the height of the nozzle throat can be changed as shown in FIG.

Since the throat area of the fixed nozzle 1 is determined by “throat width × nozzle height”, when the flow rate of the inflow gas is large, the annular throat wall 15 is separated from the nozzle end face 1b, and the nozzle height becomes high and the throat area becomes large. The area is enlarged.
Conversely, when the flow rate is small, the annular throat wall 15 is brought closer to the nozzle end face 1b, the nozzle height is reduced, and the throat area is reduced.

As described above, according to the variable displacement radial turbine of the third embodiment, the area of the nozzle throat can be adjusted in accordance with the flow rate with a simple configuration as compared with the conventional VG turbine.

Fourth Embodiment Next, a variable displacement radial turbine according to a fourth embodiment shown in FIGS. 6 to 8 will be described. In the variable displacement radial turbine according to the fourth embodiment, the movable portions 9a, 9b
Are provided rotatably around pivot points 10a and 10b, respectively.

The movable part 9a is turned around a pivot point 10a by a driving device 7 via a connecting rod 6, and the movable part 9a
When a is rotated, the movable portion 9b is also configured to rotate around the pivot point 10b by an appropriate connection mechanism (not shown). Other configurations are substantially the same as the configuration of the variable displacement radial turbine according to the first embodiment shown in FIG.

In the variable displacement radial turbine according to the fourth embodiment having the above-described structure, the gas flowing into the scroll 2 from the scroll inlet of the radial turbine passes through the scroll inner passage 2b, is guided to the fixed nozzle 1, and is guided to the throat. It is accelerated at 01a.

With the operation of the movable part 9a, the other movable part 9b is also operated. The throat width 1a is increased by closing the movable portion 9a by rotating the connecting rod 6 by the driving device 7 as shown in FIG. Conversely, when the connecting rod 6 is rotated to open the movable part 9a as shown in FIG. 8, the width of the throat 01a becomes narrow.

Since the throat area of the fixed nozzle 1 is determined by “throat width × nozzle height”, when the inflow gas has a large flow rate, as shown in FIG.
Is closed, the movable portion 9b also operates in the closing direction following the movable portion 9a by the pressure of the inflow gas. Therefore, the width of the throat 01a is increased, and the throat area is increased. At this time, since the pressure is acting, the movable parts 9a and 9b always operate in conjunction with each other.

Conversely, when the flow rate is small, as shown in FIG. 8, by opening the movable portion 9a, the movable portion 9b is actuated, the width of the throat 01a is reduced, and the throat area is reduced. Even when the gas flow rate changes, the inflow speed and the inflow angle into the turbine bucket 3 lean substantially constant, and high turbine efficiency can always be obtained.

[0038]

As described above, according to the present invention, the inflow path between the fixed nozzles serving as the inflow path to the turbine blade is shielded, and the amount of shielding of the inflow path is variably set. The present invention provides a variable displacement radial turbine provided with a shielding member that makes the turbine capacity variable, and a drive unit that drives the shielding member so that the shielding amount is variable.

In this variable displacement radial turbine,
The inflow path between the fixed nozzles is shielded by a predetermined amount by a shielding member to make the turbine capacity variable, so that the fluid can flow into the turbine blade at a predetermined flow velocity and an inflow angle regardless of a change in the fluid flow rate. Does not decrease.

Further, another variable displacement radial type turbine of the present invention has an annular throat wall having a shape overlapping with the fixed nozzle and movably disposed in the direction of the rotation axis so as to change the area of the throat portion. Drive means for variably driving the position of the annular throat wall in the direction of the rotation axis.

In this variable displacement radial turbine,
By simply changing the position of the annular throat wall in the rotation axis direction by the driving means, the inflow path area between the fixed nozzles can be changed variably, and the fluid flows into the turbine blade at a predetermined flow rate and the inflow angle regardless of the change in the fluid flow rate. And does not reduce turbine efficiency.

In still another variable displacement radial turbine according to the present invention, a notch provided at one end of each of the plurality of fixed nozzles, and an inflow path to the turbine blade by fitting into the notch. A shield member is provided which shields and variably sets a shielding amount of the inflow passage, thereby varying a turbine capacity, and a driving means for variably driving the shielding member with the shielding amount.

In the variable displacement radial turbine having the above configuration, the shielding member fits into the notch provided at one end of the fixed nozzle to variably shield the inflow path of the fluid to the turbine blade. The area of the inflow path is changed in accordance with the change in the flow rate of the fluid such as gas, so that even if the flow rate of the fluid such as gas changes, the flow rate of the fluid such as gas to the turbine blade is substantially constant. And an inflow angle, so that high turbine efficiency can always be obtained.

[Brief description of the drawings]

FIG. 1 is an axial longitudinal sectional view of a turbine rotor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is an axial longitudinal sectional view of a turbine rotor according to a second embodiment of the present invention.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2;

FIG. 5 is an axial longitudinal sectional view of a turbine rotor according to a third embodiment of the present invention.

FIG. 6 is an axial longitudinal sectional view of a turbine rotor according to a fourth embodiment of the present invention.

7 is a sectional view taken along the line VII-VII in FIG. 6, showing a state in which a movable part is closed.

FIG. 8 is a sectional view taken along the line VII-VII of FIG. 6, showing a state where a movable part is opened.

FIG. 9 is a vertical cross-sectional view in a direction orthogonal to the axis of a turbine rotor of a conventional radial turbine having a fixed nozzle.

FIG. 10 is an axial longitudinal sectional view of a turbine rotor of a radial turbine having a conventional fixed nozzle.

FIG. 11 is an explanatory view of a nozzle portion in a conventional variable displacement turbine.

[Explanation of symbols]

 01a Throat 1 Fixed nozzle 1a Notch 1b Nozzle end face 2 Scroll 2b Scroll passage 2c Scroll connecting rod 3 Turbine rotor blade 4 Turbine rotor 5 Annular throat wall 6 Connecting rod 7 Drive unit 8 Annular throat wall 9a Movable part 9b Movable Part 10a pivot point 10b pivot point 15 annular throat wall

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Shozo Maekawa 5-717-1 Fukahori-cho, Nagasaki City, Mitsubishi Heavy Industries, Ltd.

Claims (3)

[Claims] 1. A turbine blade rotatably installed,
A plurality of fixed nozzles forming an inflow path of a fluid such as gas for rotating the turbine rotor blade to the turbine rotor blade, wherein the plurality of fixed nozzles form an inflow path to the turbine rotor blade. A shielding member that shields the inflow path of the above and variably installs the amount of shielding of the inflow path, and a driving unit that variably drives the amount of shielding of the shielding member. A variable capacity radial turbine characterized by the following. 2. A turbine blade rotatably installed,
A radial turbine having a plurality of fixed nozzles forming an inflow path of a fluid such as a gas for rotating the turbine blade to the turbine blade, wherein the throat portion of the fixed nozzle has a shape overlapping the fixed nozzle. A variable capacity comprising: an annular throat wall movably disposed in a rotation axis direction so as to change an area of the throat portion; and driving means for variably driving a position in the rotation axis direction of the annular throat wall. Type radial turbine. 3. A turbine blade rotatably installed,
In a radial turbine having a plurality of fixed nozzles forming an inflow path of a fluid such as a gas for rotating the turbine blade to the turbine blade, a notch provided at one end of each of the fixed nozzles, A shielding member that fits into the notch of the turbine blade to shield the inflow path to the turbine rotor blade, and that the amount of shielding of the inflow path is variably installed to change the turbine capacity, and that the shielding member is shielded. And a drive means for driving the amount variably.