U.S. patent application number 13/643775 was filed with the patent office on 2013-10-24 for aerated swirling vertical shaft with double volute chambers.
This patent application is currently assigned to SICHUAN UNIVERSITY. The applicant listed for this patent is Jiangang Chen, Jun Deng, Gang Lei, Shanjun Liu, Jingxue Qu, Yu Ren, Zhong Tian, Wei Wang, Weilin Xu, Jianmin Zhang. Invention is credited to Jiangang Chen, Jun Deng, Gang Lei, Shanjun Liu, Jingxue Qu, Yu Ren, Zhong Tian, Wei Wang, Weilin Xu, Jianmin Zhang.
Application Number | 20130276926 13/643775 |
Document ID | / |
Family ID | 41520800 |
Filed Date | 2013-10-24 |
United States Patent
Application |
20130276926 |
Kind Code |
A9 |
Zhang; Jianmin ; et
al. |
October 24, 2013 |
Aerated Swirling Vertical Shaft with Double Volute Chambers
Abstract
An aerated swirling vertical shaft with double volute chambers
comprises an upper volute chamber (2) and a first shrinking section
(3) beneath the upper volute chamber (2), a venting passage (4)
outside the upper volute chamber (2), a vertical shaft section (7)
beneath the first shrinking section (3), as well as an aerated
lower volute chamber (5) and a second shrinking section (6)
communicated with the aerated lower volute chamber (5) between the
first shrinking section (3) and the vertical shaft section (7),
wherein the upper end of the aerated lower volute chamber (5) is
connected with the first shrinking section (3), the lower end of
the second shrinking section (6) is connected with the vertical
shaft section (7); the upper end of the venting passage (4) is
communicated with the atmosphere and the lower end is communicated
with the aerated lower volute chamber (5). The water stream in the
vertical shaft can be discharged smoothly and the wall surface of
the vertical shaft may avoid being destroyed due to cavitation and
cavitation erosion.
Inventors: |
Zhang; Jianmin; (Chengdu,
CN) ; Xu; Weilin; (Chengdu, CN) ; Liu;
Shanjun; (Chengdu, CN) ; Wang; Wei; (Chengdu,
CN) ; Qu; Jingxue; (Chengdu, CN) ; Deng;
Jun; (Chengdu, CN) ; Tian; Zhong; (Chengdu,
CN) ; Chen; Jiangang; (Chengdu, CN) ; Lei;
Gang; (Chengdu, CN) ; Ren; Yu; (Chengdu,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Zhang; Jianmin
Xu; Weilin
Liu; Shanjun
Wang; Wei
Qu; Jingxue
Deng; Jun
Tian; Zhong
Chen; Jiangang
Lei; Gang
Ren; Yu |
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu
Chengdu |
|
CN
CN
CN
CN
CN
CN
CN
CN
CN
CN |
|
|
Assignee: |
SICHUAN UNIVERSITY
Chengdu, Sichuan Province
CN
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20130068332 A1 |
March 21, 2013 |
|
|
Family ID: |
41520800 |
Appl. No.: |
13/643775 |
Filed: |
July 28, 2010 |
PCT Filed: |
July 28, 2010 |
PCT NO: |
PCT/CN2010/075520 PCKC 00 |
371 Date: |
October 26, 2012 |
Current U.S.
Class: |
137/808 |
Current CPC
Class: |
F03B 11/002 20130101;
Y10T 137/2087 20150401; F03B 13/105 20130101; E02B 9/06 20130101;
F16L 9/00 20130101; Y02E 10/22 20130101; Y02E 10/226 20130101; Y02E
10/20 20130101 |
Class at
Publication: |
137/808 |
International
Class: |
F16L 9/00 20060101
F16L009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 28, 2009 |
CN |
200910060125.2 |
Claims
1. An aerated swirling vertical shaft with double volute chambers,
comprising: an upper volute chamber (2) and a first shrinking
section (3) beneath the upper volute chamber (2), a venting passage
(4) outside the upper volute chamber (2), a vertical shaft section
(7) beneath the first shrinking section (3), and further comprising
an aerated lower volute chamber (5) and a second shrinking section
(6) communicated with the aerated lower volute chamber (5) between
the first shrinking section (3) and the vertical shaft section (7),
wherein the upper end of the aerated lower volute chamber (5) is
connected with the first shrinking section (3), the lower end of
the second shrinking section (6) is connected with the vertical
shaft section (7); the upper end of the venting passage (4) is
communicated with the atmosphere and the lower end is communicated
with the aerated lower volute chamber (5).
2. The aerated swirling vertical shaft with double volute chambers
according to claim 1, wherein the axis projection of the lower end
surface of the venting passage (4) is located within the aerated
lower volute chamber (5).
3. The aerated swirling vertical shaft with double volute chambers
according to claim 2, wherein the venting passage (4) extends
linearly.
4. The aerated swirling vertical shaft with double volute chambers
according to claim 3, wherein both the upper volute chamber and the
aerated lower volute chamber (5) are cylindrical.
5. The aerated swirling vertical shaft with double volute chambers
according to claim 4, wherein there are at least two venting
passages (4), which are provided around the upper volute chamber
(2) uniformly.
6. The aerated swirling vertical shaft with double volute chambers
according to claim 1, wherein a diameter D.sub.2 of the aerated
lower volute chamber (5) is greater than or equal to a diameter
D.sub.1 of the upper volute chamber (2).
7. The aerated swirling vertical shaft with double volute chambers
according to claim 6, wherein the length L.sub.1 of the upper
volute chamber (2) is 2.0 D.sub.1 to 3.0 D.sub.1, the ratio of the
length L.sub.2 of the first shrinking section (3) to the length
L.sub.1 of the upper volute chamber (2) is 1:2 to 1:1, the gradient
i.sub.1 of the first shrinking section (3) is 1:15 to 1:10, wherein
D.sub.1 is the diameter of the upper volute chamber (2).
8. The aerated swirling vertical shaft with double volute chambers
according to claim 7, wherein the length L.sub.3 of the aerated
lower volute chamber (5) is 0.4 D.sub.2 to 1.0 D.sub.2, the ratio
of the length L.sub.4 of the second shrinking section (6) to the
length L.sub.3 of the aerated lower volute chamber (5) is 2:1 to
4:1, the gradient i.sub.2 of the second shrinking section (6) is
1:15 to 1:10, wherein D.sub.2 is the diameter of the aerated lower
volute chamber.
9. The aerated swirling vertical shaft with double volute chambers
according to claim 1, wherein the length L.sub.1 of the upper
volute chamber (2) is 2.0 D.sub.1 to 3.0 D.sub.1, the ratio of the
length L.sub.2 of the first shrinking section (3) to the length
L.sub.1 of the upper volute chamber (2) is 1:2 to 1:1, the gradient
i.sub.1 of the first shrinking section (3) is 1:15 to 1:10, wherein
D.sub.1 is the diameter of the upper volute chamber (2).
10. The aerated swirling vertical shaft with double volute chambers
according to claim 9, wherein the length L.sub.3 of the aerated
lower volute chamber (5) is 0.4 D.sub.2 to 1.0 D.sub.2, the ratio
of the length L.sub.4 of the second shrinking section (6) to the
length L.sub.3 of the aerated lower volute chamber (5) is 2:1 to
4:1, the gradient i.sub.2 of the second shrinking section (6) is
1:15 to 1:10, wherein D.sub.2 is the diameter of the aerated lower
volute chamber.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to a swirling vertical shaft,
which is an energy dissipating facility used for hydraulic and
hydropower engineering, in particular to an aerated swirling
vertical shaft which is suitable for high head and large
discharge.
BACKGROUND OF THE INVENTION
[0002] The engineering practice shows that, under the condition of
large discharge and high head, the energy dissipation of the
swirling vertical shaft encounters the following problems, that is,
1) excessive flow velocity in the vertical shaft increases the
risks of cavitation and cavitation erosion on the wall surface; 2)
due to the centrifugal force of water stream, it is difficult to
perform aeration by using the conventional annular aeration ridge,
the function of aeration and cavitation mitigation can not
work.
[0003] Chinese patent application with publishing No. CN 101294377A
provides a swirling vertical shaft provided with an aeration ridge.
The aeration ridge is arranged on the wall surface of the lower
middle section of the vertical shaft, and formed by gradually
shrinking the vertical shaft connecting with the upper flat section
of a flood discharging tunnel from the middle part to the lower
middle part and then suddenly expanding the wall surface. Compared
to the swirling vertical shaft provided with a conventional annular
aeration ridge, although the aeration condition of the water stream
can be improved to enable near-wall water layer at the lower
reaches to become into aerated water streams and mitigate the
damage of overflowing section at the lower middle part of the
vertical shaft caused by cavitation erosion. However, the swirling
vertical shaft of such a structure is only suitable for small
discharge for the small volume of the cavity for containing air
formed by suddenly expanding makes the amount of air aerated into
the water stream small. Under the condition of large discharge and
high head, it is difficult to fully aerate the water stream in the
vertical shaft, the water stream in the vertical shaft cannot be
discharged smoothly, and the concentration of the air mixed in the
water stream cannot be increased effectively under the condition of
large discharge and high head.
SUMMARY OF THE INVENTION
[0004] The objective of the present invention is to overcome the
defects of the prior art and provide an aerated swirling vertical
shaft with double volute chambers to solve the problem of
insufficient aeration on the wall surface caused by a sealed cavity
of the swirling vertical shaft under the condition of large
discharge and high head, so that the water stream in the vertical
shaft can be discharged smoothly and the wall surface of the
vertical shaft may avoid being destroyed due to cavitation and
cavitation erosion.
[0005] The present invention provides an aerated swirling vertical
shaft with double volute chambers, comprising an upper volute
chamber and a first shrinking section beneath the upper volute
chamber, a venting passage outside the upper volute chamber, a
vertical shaft section beneath the first shrinking section, and
further comprising an aerated lower volute chamber and a second
shrinking section communicated with the aerated lower volute
chamber between the first shrinking section and the vertical shaft
section, wherein the upper end of the aerated lower volute chamber
is connected with the first shrinking section, the lower end of the
second shrinking section is connected with the vertical shaft
section; the upper end of the venting passage is communicated with
the atmosphere and the lower end is communicated with the aerated
lower volute chamber.
[0006] By experiments, the aerated swirling vertical shaft with
double volute chambers provided by the present invention preferably
adopts the following structural parameters:
[0007] 1. The diameter D.sub.1 of the upper volute chamber is
determined according to the flow rate of water stream entering into
the vertical shaft, and the aerated lower volute chamber has a
diameter D.sub.2 which is greater than or equal to the diameter
D.sub.1 of the upper volute chamber.
[0008] 2. The length L.sub.1 of the upper volute chamber is 2.0
D.sub.1 to 3.0 D.sub.1, the ratio of the length L.sub.2 of the
first shrinking section to the length L.sub.1 of the upper volute
chamber is 1:2 to 1:1, the gradient i.sub.1 of the first shrinking
section (3) is 1:15 to 1:10, wherein D.sub.1 is the diameter of the
upper volute chamber.
[0009] 3. The length L.sub.3 of the aerated lower volute chamber is
0.4 D.sub.2 to 1.0 D.sub.2, the ratio of the length L.sub.4 of the
second shrinking section to the length L.sub.3 of the aerated lower
volute chamber is 2:1 to 4:1, the gradient i.sub.2 of the second
shrinking section is 1:15 to 1:10, wherein D.sub.2 is the diameter
of the aerated lower volute chamber.
[0010] The present invention has the following technical
effects:
[0011] 1. Since the aerated lower volute chamber is provided
beneath the first shrinking section which is provided beneath the
lower part of the upper volute chamber, the air flows through the
venting passage and flows into the aerated lower volute chamber. As
the aerated lower volute chamber can contain more air to be mixed
with the water stream spouted out of the first shrinking section,
the content of air entering the water stream in the vertical shaft
section is effectively increased, and the problem of insufficient
aeration on the wall surface caused by a sealed cavity of the
swirling vertical shaft is avoided. The aerated swirling vertical
shaft with double volute chambers has more remarkable aeration
effects under the condition of large discharge and high head, is
capable of fully mixing water and air, increases the content of air
in the water stream significantly, stabilizes the water stream
form, and further achieves the effect of eliminating the damage on
the wall surface of the vertical shaft caused by cavitation
erosion, and ensuring the safe operation of the vertical shaft and
the flood discharge tunnel.
[0012] 2. Optimization of structural parameters ensures the
stability of aeration and cavitation mitigation effects of the
aerated swirling vertical shaft with double volute chambers
provided by the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a structure diagram of the aerated swirling
vertical shaft with double volute chambers according to the present
invention (viewed from section VI-VI of FIG. 2);
[0014] FIG. 2 is a top view of FIG. 1, showing a connection
relation between the aerated swirling vertical shaft with double
volute chambers and an approach channel, a pressing slope section
and a flood discharging tunnel according to the present
invention;
[0015] FIG. 3 is a I-I sectional view of FIG. 1, in which the
section is the section of an upper volute chamber;
[0016] FIG. 4 is a II-II sectional view of FIG. 1, in which the
section is the section of an aerated lower volute chamber;
[0017] FIG. 5 is a III-III sectional view of FIG. 1, in which the
section is the section of a vertical shaft section;
[0018] FIG. 6 is a IV-IV sectional view of FIG. 1, in which the
section is the section of a pressing slope section; and
[0019] FIG. 7 is a V-V sectional view of FIG. 1, in which the
section is the section of a flood discharging tunnel.
[0020] In these figures, 1-approach channel, 2-upper volute
chamber, 3-first shrinking section, 4-venting passage, 5-aerated
lower volute chamber, 6-second shrinking section, 7-vertical shaft
section, 8-anti-arc section, 9-pressing slope section, 10-flood
discharging tunnel, D.sub.1-diameter of upper volute chamber,
D.sub.2-diameter of aerated lower volute chamber, D.sub.3-diameter
of vertical shaft section, L.sub.1-length of upper volute chamber,
L.sub.2-length of first shrinking section, i.sub.1-gradient of
first shrinking section, L.sub.3-length of aerated lower volute
chamber, L.sub.4-length of second shrinking section,
i.sub.2-gradient of second shrinking section, L.sub.5-length of
vertical shaft section, L.sub.6-height from bottom plate of
vertical shaft to downstream connection section, L.sub.7-length of
pressing slope, i.sub.3-gradient of pressing slope section,
R-radius of anti-arc section, B-width of flood discharging tunnel,
H-height of flood discharging tunnel.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The embodiments of the present invention will be described
in detail below as shown in drawings. The structure of the aerated
swirling vertical shaft with double volute chambers of the present
invention will be further described below as shown in drawings. The
aerated swirling vertical shaft with double volute chambers in the
following embodiments is designed based on a flood discharging
tunnel in a pivotal project of a certain hydropower station. The
flood discharging tunnel of the vertical shaft is of swirling flow
internal energy dissipation type, the elevation of the bottom plate
of the flood discharging tunnel of the vertical shaft is 2690 m,
the elevation of the top is 2852 m, and the flow velocity V of the
approach channel is 12 m/s to 20 m/s.
[0022] Embodiment 1 is described as follows:
[0023] In this embodiment, the structure of the aerated swirling
vertical shaft with double volute chambers is shown in FIG. 1 and
FIG. 2, which comprises an upper volute chamber 2, a first
shrinking section 3 beneath the upper volute chamber 2, an aerated
lower volute chamber 5, a second shrinking section 6 beneath the
aerated lower volute chamber 5, a vertical shaft section 7 and a
venting passage 4. The first shrinking section 3 beneath the upper
volute chamber is connected with the aerated lower volute chamber
5, and the second shrinking section 6 beneath the aerated lower
volute chamber is connected with the vertical shaft section 7.
There are two venting passages 4, which are symmetrically installed
on the outer walls of the upper volute chamber and the first
shrinking section beneath the upper volute chamber. The upper ends
of the venting passages are communicated with the atmosphere, and
the lower ends are connected with the top of the aerated lower
volute chamber. The upper volute chamber 2 is connected with the
approach channel 1, and the water stream in the approach channel is
introduced into the vertical shaft from the upper volute chamber
tangentially. The lower part of the vertical shaft section 7 is
communicated with the flood discharging tunnel 10 through the
anti-arc section 8 and pressing slope section 9.
[0024] It can also be seen from the figure that, both of the upper
volute chamber 2 and the aerated lower volute chamber 5 are
preferably cylindrical to facilitate the manufacture. The venting
passage 4 is designed such that the axial projection of the lower
end surface of the venting passage 4 is located within the aerated
lower volute chamber, so as to expand the volume for containing air
as large as possible. Moreover, a jet flow is formed when the water
stream from the upper volute chamber 2 flows through the first
shrinking section 3. The volume of the jet flow in the suddenly
expanded cylindrical aerated lower volute chamber 5 is small, so
the usable volume of the aerated lower volute chamber 5 for
containing air from the venting passage is increased. Then, during
the advancing process, the jetted water flow diffuses and air
aerates in the jetted water flow to form an aerated layer. At the
same time, the air is entrapped during the downward process, so
that the near-wall water layers at the lower reaches become into
aerated water streams, resulting in the air mixing concentration in
the water stream being not less than the minimum concentration
value effective for corrosion prevention, thereby achieving the
improvement in corrosion prevention performance under the condition
of high head and of large discharge. It can also be seen from the
figure that, the venting passage 4 extends linearly, which makes it
easy to manufacture. In this embodiment, two venting passages 4 are
taken as an example, which are arranged around the upper volute
chamber 2 uniformly. In practical use, the number of the venting
passages 4 is not limited to two. The second shrinking section 6 is
used for transitionally connecting the cylindrical aerated lower
volute chamber 5 and the vertical shaft section 7.
[0025] In this embodiment, the flow rate of water stream is 400
m.sup.3/s, and the aerated swirling vertical shaft with double
volute chambers has relevant structural parameters as follows:
[0026] The cross section of the upper volute chamber 2 is shown in
FIG. 3, in which the diameter D.sub.1 is 10 m, and the length
L.sub.1 is 30 m; the length L.sub.2 of the first shrinking section
3 on the lower part of the upper volute chamber is 15 m, and the
gradient i.sub.1 is 1:10. The cross section of the aerated lower
volute chamber 5 is shown in FIG. 4, in which the diameter D.sub.2
is 10 m, and the length L.sub.3 is 5 m; the length L.sub.4 of the
second shrinking section 6 on the lower part of the upper volute
chamber is 20 m, and the gradient i.sub.2 is 1:15. The cross
section of the vertical shaft section 7 is shown in FIG. 5, wherein
the diameter D.sub.3 is 7 m, the length L.sub.5 is 92 m, the height
L.sub.6 from the bottom plate of vertical shaft to the downstream
connection section is 10 m, and the radius R of the anti-arc
section 8 is 15 m. The cross section of the pressing slope section
9 is shown in FIG. 6, in which the length L.sub.7 is 35 m, and the
gradient i.sub.3 is 1:15. The cross section of the flood
discharging tunnel 10 is shown in FIG. 7, in which the width B is 5
m, and the height H is 7 m.
[0027] Proved by the experiments, the aerated swirling vertical
shaft with double volute chambers according to the embodiment of
the present invention has remarkable aeration effects under the
condition of large discharge and high head, and is capable of
increasing the content of air in the water stream effectively by 4%
or more.
[0028] Embodiment 2 is described as follows:
[0029] In this embodiment, the structure of the aerated swirling
vertical shaft with double volute chambers is shown in FIG. 1 and
FIG. 2. Its components and connection position of each component
are the same as those in Embodiment 1, differing from Embodiment 1
in that the flow rate of water stream in the vertical shaft is 600
m.sup.3/s, thereby changing the structural parameters. The aerated
swirling vertical shaft with double volute chambers has relevant
structural parameters as follows:
[0030] The cross section of the upper volute chamber 2 is shown in
FIG. 3, in which the diameter D.sub.1 is 12 m, and the length
L.sub.1 thereof is 24 m; the length L.sub.2 of the first shrinking
section 3 on the lower part of the upper volute chamber is 24 m,
and the gradient i.sub.1 is 1:12. The cross section of the aerated
lower volute chamber 5 is shown in FIG. 4, in which the diameter
D.sub.2 is 14 m, and the length L.sub.3 thereof is 12 m; the length
L.sub.4 of the second shrinking section 6 on the lower part of the
aerated upper volute chamber is 30 m, and the gradient i.sub.2 is
1:10. The cross section of the vertical shaft section 7 is shown in
FIG. 5, in which the diameter D.sub.3 is 8 m, and the length
L.sub.5 is 72 m, the height L.sub.6 from the bottom plate of
vertical shaft to the downstream connection section is 10 m, and
the radius R of the anti-arc section 8 is 20 m. The cross section
of the pressing slope section 9 is shown in FIG. 6, in which the
length L.sub.7 is 30 m, and the gradient i.sub.3 is 1:10. The cross
section of the flood discharging tunnel 10 is as shown in FIG. 7,
in which the width B is 5 m, and the height H is 7 m.
[0031] Proved by the experiments, the aerated swirling vertical
shaft with double volute chambers according to the embodiment of
the present invention has remarkable aeration effects under the
condition of large discharge and high head, and is capable of
increasing the content of air in the water stream effectively by 4%
or more.
[0032] Above contents only describe the preferred embodiments of
the present invention and are not intended to limit the present
invention; for one skilled in the art, the present invention may
have various modifications and changes. Any modifications,
equivalent replacements and improvements made within the spirit and
principle of the present invention should be included within the
protection scope of the present invention.
* * * * *