JP2000064994A - Centrifugal compressor - Google Patents

Centrifugal compressor

Info

Publication number
JP2000064994A
JP2000064994A JP10235534A JP23553498A JP2000064994A JP 2000064994 A JP2000064994 A JP 2000064994A JP 10235534 A JP10235534 A JP 10235534A JP 23553498 A JP23553498 A JP 23553498A JP 2000064994 A JP2000064994 A JP 2000064994A
Authority
JP
Japan
Prior art keywords
diffuser
volute
vane
outlet
impeller
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP10235534A
Other languages
Japanese (ja)
Inventor
Kazumi Hasegawa
和三 長谷川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
IHI Corp
Original Assignee
IHI Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by IHI Corp filed Critical IHI Corp
Priority to JP10235534A priority Critical patent/JP2000064994A/en
Publication of JP2000064994A publication Critical patent/JP2000064994A/en
Pending legal-status Critical Current

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Abstract

PROBLEM TO BE SOLVED: To reduce incurring of a loss by pointing a flow to a peripheral direction right before entrance to a volute and through reduction of a revolution speed component in the volute by a method wherein a diffuser and the volute are disposed on the outside in a radial direction of an impeller and an outlet vane is disposed in the vicinity of the volute of the diffuser. SOLUTION: A diffuser 3 is disposed on the outside in a radial direction of an impeller 2, and a volute (a vortex chamber) 4 is disposed on the outside in a radial direction of the diffuser 3. When an impeller 2 is rotationally driven, fluid is sucked from an axial direction and discharged to the outside in a radial direction. The diffuser 3 decelerates high speed fluid discharged from the impeller 2 and speed energy thereof is converted into pressure energy. Further, a plurality of intermediate vanes 7 are disposed in the intermediate position in a radial direction of the diffuser 3 and a plurality of outlet vanes 8 are disposed on the outside in a radial direction of an intermediate vane 7. This constitution points a flow in a peripheral direction right before outgoing of fluid from the diffuser 3 and reduces incurring of a loss through reduction of a revolving component in the volute 4.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、エア等の各種流体
の加圧供給に用いる遠心圧縮機に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal compressor used for pressurizing and supplying various fluids such as air.

【0002】[0002]

【従来の技術】遠心圧縮機では、インペラの径方向外側
にディフューザとボリュート(渦巻室)とを設け、イン
ペラから出た高速流体をディフューザで減速し、圧力に
変換させ、ボリュートに集めて外部に吐出するようにな
っている。
2. Description of the Related Art In a centrifugal compressor, a diffuser and a volute (vortex chamber) are provided radially outside of an impeller, and high-speed fluid discharged from the impeller is decelerated by the diffuser, converted into pressure, collected into a volute, and collected outside. It discharges.

【0003】[0003]

【発明が解決しようとする課題】ところで、ディフュー
ザ内の流体は半径方向と周方向(接線方向)との速度成
分を持ちながらボリュート内に流入し、ボリュート内を
周方向に流れて外部に吐出される。このとき図4に示す
ように、半径方向の速度成分V1 がボリュートU内での
旋回を生じさせ、損失を生じさせている。即ち、ボリュ
ート内を周方向に流れる速度成分のみが有効に仕事をす
るため、これに直交する旋回速度成分は何等仕事をせ
ず、ロスとなってしまう。
By the way, the fluid in the diffuser flows into the volute while having velocity components in the radial direction and the circumferential direction (tangential direction), flows in the volute in the circumferential direction, and is discharged to the outside. You. As shown in FIG. 4 at this time, velocity components V 1 of the radial cause swirling in the volute U, and causing loss. That is, only the velocity component flowing in the circumferential direction in the volute works effectively, so that the turning velocity component orthogonal to this does not perform any work and is lost.

【0004】[0004]

【課題を解決するための手段】本発明に係る遠心圧縮機
は、インペラの径方向外側にディフューザとボリュート
とを設け、上記ディフューザの上記ボリュート近傍に出
口ベーンを設けたものである。
A centrifugal compressor according to the present invention is provided with a diffuser and a volute radially outside an impeller, and an outlet vane near the volute of the diffuser.

【0005】これによれば、ボリュートに入る直前で流
れを周方向に向けられるため、ボリュート内での旋回速
度成分を減らし、ロスを低減できる。
[0005] According to this, since the flow can be directed in the circumferential direction immediately before entering the volute, the turning speed component in the volute can be reduced, and the loss can be reduced.

【0006】なお、上記ディフューザにおいて、上記出
口ベーンの径方向内側に中間ベーンが設けられ、上記出
口ベーンの出口の向きが、上記中間ベーンの出口の向き
より接線方向に近付けられるのが好ましい。
In the diffuser, it is preferable that an intermediate vane is provided radially inward of the outlet vane, and the outlet of the outlet vane is closer to the tangential direction than the outlet of the intermediate vane.

【0007】また、上記インペラの半径をR2 、その半
径方向における上記出口ベーンの入口位置をR4 とし
て、1.5≦R2 /R4 ≦1.7の関係が満たされるよ
う上記出口ベーンが配置されるのが好ましい。
[0007] Further, assuming that the radius of the impeller is R 2 and the inlet position of the outlet vane in the radial direction is R 4 , the outlet vane satisfies the relationship of 1.5 ≦ R 2 / R 4 ≦ 1.7. Is preferably arranged.

【0008】また、上記ディフューザの半径方向の長さ
をLとしたとき、その半径方向外側端の位置から0以上
L/10以下の位置に上記出口ベーンの出口が位置され
るのが好ましい。
When the length of the diffuser in the radial direction is L, it is preferable that the outlet of the outlet vane is located at a position of 0 to L / 10 from the position of the radially outer end.

【0009】[0009]

【発明の実施の形態】以下、本発明の好適な実施の形態
を添付図面に基づいて詳述する。
Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

【0010】図1、図2に示すように、かかる遠心圧縮
機1では、インペラ2の径方向外側にディフューザ3
が、ディフューザ3の径方向外側にボリュート(渦巻
室)4が設けられる。インペラ2は図示しない駆動装置
(モータ、タービン等)により回転駆動され、流体を軸
方向から吸入して半径方向外側に吐出する。ディフュー
ザ3は、インペラ2から吐出された高速流体を減速し、
その速度エネルギを圧力エネルギに変換するものであ
る。ディフューザ3を出た流体はボリュート4に流入
し、ボリュート4内を周方向に流れ、ボリュート出口5
から吐出される。なおディフューザ3及びボリュート4
はコンプレッサケーシング6によって区画される。
As shown in FIGS. 1 and 2, in such a centrifugal compressor 1, a diffuser 3 is provided radially outside an impeller 2.
However, a volute (vortex chamber) 4 is provided radially outside the diffuser 3. The impeller 2 is rotationally driven by a drive device (motor, turbine, or the like) (not shown), and sucks fluid from the axial direction and discharges the fluid outward in the radial direction. The diffuser 3 decelerates the high-speed fluid discharged from the impeller 2,
The velocity energy is converted into pressure energy. The fluid that has exited the diffuser 3 flows into the volute 4, flows in the volute 4 in the circumferential direction, and has a volute outlet 5.
Is discharged from. Diffuser 3 and Volute 4
Is partitioned by the compressor casing 6.

【0011】ここではディフューザ3がベーン付ディフ
ューザとなっている。即ち、ディフューザ3の半径方向
中間位置に複数の中間ベーン7が設けられる。ただし、
ここでは中間ベーン7の半径方向外側に複数の出口ベー
ン8が追加して設けられる。出口ベーン8はディフュー
ザ3のボリュート4近傍に設けられる。
Here, the diffuser 3 is a diffuser with vanes. That is, a plurality of intermediate vanes 7 are provided at radially intermediate positions of the diffuser 3. However,
Here, a plurality of outlet vanes 8 are additionally provided radially outside the intermediate vane 7. The outlet vane 8 is provided near the volute 4 of the diffuser 3.

【0012】中間ベーン7及び出口ベーン8は、インペ
ラ2から出た流体を周方向に方向付け、その半径方向速
度成分を減じると共に周方向(接線方向)速度成分を増
し、ボリュート4内での流れの周方向速度成分を増すた
めのものである。従来のベーン付ディフューザでは中間
ベーン7に相当するものしかなかったため、ディフュー
ザ3内の流れの半径方向速度成分を十分消失しきれず、
前述したようなボリュート4内での旋回流を生じさせ、
ロスとなっていた。本案では、ボリュート4近傍ないし
入口直前に出口ベーン8を設けたため、ディフューザ3
を出る直前で流れをより周方向に向けられ、ボリュート
4内での旋回成分を減少し、周方向成分を増してロスを
低減できる。
The intermediate vane 7 and the outlet vane 8 direct the fluid exiting the impeller 2 in the circumferential direction, reduce its radial velocity component and increase its circumferential (tangential) velocity component, and flow in the volute 4. In order to increase the circumferential velocity component of In the conventional diffuser with vanes, only the one corresponding to the intermediate vane 7 was used, so that the radial velocity component of the flow in the diffuser 3 could not be completely eliminated,
Causing a swirling flow in the volute 4 as described above,
Lost. In the present invention, since the outlet vane 8 is provided near the volute 4 or immediately before the inlet, the diffuser 3
Immediately before exiting, the flow can be directed in the circumferential direction, the swirling component in the volute 4 can be reduced, and the loss can be reduced by increasing the circumferential component.

【0013】ここで図3に示すように、インペラ2の半
径をR2 とすると、ボリュート4の入口の半径R5
1.8≦R5 /R2 ≦2.0を満たす程度とされるのが
通常である。そして中間ベーン7の入口9の半径R3
3 /R2 =約1.1を満たす程度である。よって中間
ベーン7の入口9の上流側にベーンレス部分が設けられ
る。
As shown in FIG. 3, if the radius of the impeller 2 is R 2 , the radius R 5 of the inlet of the volute 4 is set to a value satisfying 1.8 ≦ R 5 / R 2 ≦ 2.0. Is usually the case. The radius R 3 of the inlet 9 of the intermediate vane 7 is such that R 3 / R 2 = about 1.1 is satisfied. Therefore, a vaneless portion is provided upstream of the inlet 9 of the intermediate vane 7.

【0014】中間ベーン7の半径方向に対する角度はそ
れほど大きくできず、中間ベーン7はいわゆる立った状
態にある。これは、中間ベーン7をあまり寝かすと流体
の移動距離が増しロスが増えるし、中間ベーン7には半
径方向速度成分の多い高速流体が当たるからである。し
かし、これでは半径方向速度成分を十分消失することが
できない。また中間ベーン7を寝かしても中間ベーン7
を出た後は流体が再び半径方向外側に流れてしまう。
The angle of the intermediate vane 7 with respect to the radial direction cannot be so large, and the intermediate vane 7 is in a so-called standing state. This is because if the intermediate vane 7 is laid too much, the moving distance of the fluid increases and the loss increases, and the intermediate vane 7 is hit by a high-speed fluid having a large radial velocity component. However, this cannot sufficiently eliminate the radial velocity component. Even if the intermediate vane 7 is laid down, the intermediate vane 7
After flowing out, the fluid flows again radially outward.

【0015】これに対し、出口ベーン8はボリュート4
近傍に位置するので、中間ベーン7より寝かすことがで
きる。即ち出口ベーン8には、十分減速され、中間ベー
ン7で予め周方向に向けられた後の流体が当たるし、出
口ベーン8を出た後の流体も即座にボリュート4内に流
入し、移動距離が増えないからである。よって出口ベー
ン8は中間ベーン7より半径方向に対する角度を増し、
周方向ないし接線方向に近付けるようにする。これによ
りボリュート4内の旋回速度成分を効果的に減じ、ロス
を低減できると共に、周方向速度成分を増して圧縮機全
体の効率を改善できる。
On the other hand, the outlet vane 8 is
Since it is located in the vicinity, it can be laid down from the intermediate vane 7. That is, the outlet vane 8 is sufficiently decelerated, and the fluid that has been directed in the circumferential direction in advance by the intermediate vane 7 hits, and the fluid that has exited the outlet vane 8 immediately flows into the volute 4 and travels a distance Is not increasing. Therefore, the outlet vane 8 has a larger angle with respect to the radial direction than the intermediate vane 7,
Be close to the circumferential or tangential direction. As a result, the turning speed component in the volute 4 can be effectively reduced, the loss can be reduced, and the circumferential speed component can be increased to improve the efficiency of the entire compressor.

【0016】このように、かかる圧縮機1ではディフュ
ーザ3内の流れを2段階で周方向に方向付けるようにな
っている。
As described above, in the compressor 1, the flow in the diffuser 3 is circumferentially directed in two stages.

【0017】図3に示すように、出口ベーン8の向きと
しては、その出口10を代表位置にとると、接線方向長
さAと半径方向長さBとの比B/Aが1/20≦B/A
≦1/15となるようにするのが好ましい。この値は当
然中間ベーン7のもの(B1/A1 )より小さい。
As shown in FIG. 3, when the outlet 10 is located at a representative position, the ratio B / A of the tangential length A to the radial length B is 1/20 ≦ B / A
It is preferable to satisfy ≦ 1/15. This value is naturally smaller than that of the intermediate vane 7 (B 1 / A 1 ).

【0018】また、出口ベーン8の配置位置としては、
半径方向における出口ベーン8の入口11の位置をR4
として1.5≦R4 /R2 ≦1.7の関係が満たされる
ようにするのが好ましい。
The position of the outlet vane 8 is as follows.
The position of the inlet 11 of the outlet vane 8 in the radial direction is R 4
It is preferable that the relationship 1.5 ≦ R 4 / R 2 ≦ 1.7 is satisfied.

【0019】或いは、ディフューザ3の半径方向の長さ
をLとしたとき、その半径方向外側端(出口端)の位置
から0以上、LB =L/10以下の位置に、出口ベーン
8の出口10を位置させるのが好ましい。ここでL=0
とは、出口ベーン8の出口10がディフューザ3の出口
端に接することを意味する。
Alternatively, assuming that the length of the diffuser 3 in the radial direction is L, the outlet of the outlet vane 8 is located between 0 and L B = L / 10 or less from the position of the radially outer end (outlet end). Preferably, 10 is located. Where L = 0
Means that the outlet 10 of the outlet vane 8 contacts the outlet end of the diffuser 3.

【0020】以上、本発明は上記実施の形態に限らず他
の実施の形態を採ることもできる。例えば、通常のベー
ン無ディフューザ(中間ベーン無し)に出口ベーンのみ
を追加してもよい。中間ベーンの長さや角度等も任意で
ある。
As described above, the present invention is not limited to the above-described embodiment, and can adopt other embodiments. For example, only an outlet vane may be added to a normal vaneless diffuser (no intermediate vane). The length and angle of the intermediate vane are also arbitrary.

【0021】[0021]

【発明の効果】本発明は次の如き優れた効果を発揮す
る。
The present invention exhibits the following excellent effects.

【0022】(1) ボリュート内の流れの旋回速度成
分を減じ、ロスを低減できる。
(1) The swirling speed component of the flow in the volute can be reduced to reduce the loss.

【0023】(2) ボリュート内の流れの周方向速度
成分を増し、圧縮機全体の効率を高められる。
(2) The circumferential velocity component of the flow in the volute can be increased, and the efficiency of the entire compressor can be increased.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明に係る遠心圧縮機を示す正面図である。FIG. 1 is a front view showing a centrifugal compressor according to the present invention.

【図2】本発明に係る遠心圧縮機を示す側面図である。FIG. 2 is a side view showing a centrifugal compressor according to the present invention.

【図3】本発明に係る遠心圧縮機の各部の位置関係を示
す正面図である。
FIG. 3 is a front view showing a positional relationship of each part of the centrifugal compressor according to the present invention.

【図4】ボリュート内の流れの旋回速度成分を示す側面
図である。
FIG. 4 is a side view showing a swirl speed component of a flow in the volute.

【符号の説明】[Explanation of symbols]

1 遠心圧縮機 2 インペラ 3 ディフューザ 4 ボリュート 7 中間ベーン 8 出口ベーン 10 出口 L ディフューザの半径方向の長さ R2 インペラの半径 R4 出口ベーンの入口位置DESCRIPTION OF SYMBOLS 1 Centrifugal compressor 2 Impeller 3 Diffuser 4 Volute 7 Intermediate vane 8 Exit vane 10 Exit L Radial length of diffuser R 2 Radius of impeller R 4 Inlet position of exit vane

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 インペラの径方向外側にディフューザと
ボリュートとを設け、上記ディフューザの上記ボリュー
ト近傍に出口ベーンを設けたことを特徴とする遠心圧縮
機。
1. A centrifugal compressor comprising: a diffuser and a volute provided radially outside an impeller; and an outlet vane provided near the volute of the diffuser.
【請求項2】 上記ディフューザにおいて、上記出口ベ
ーンの径方向内側に中間ベーンが設けられ、上記出口ベ
ーンの出口の向きが、上記中間ベーンの出口の向きより
接線方向に近付けられる請求項1記載の遠心圧縮機。
2. The diffuser according to claim 1, wherein an intermediate vane is provided radially inward of the outlet vane, and an outlet of the outlet vane is closer to a tangential direction than an outlet of the intermediate vane. Centrifugal compressor.
【請求項3】 上記インペラの半径をR2 、その半径方
向における上記出口ベーンの入口位置をR4 として、
1.5≦R4 /R2 ≦1.7の関係が満たされるよう上
記出口ベーンが配置される請求項1又は2記載の遠心圧
縮機。
3. The radius of the impeller is R 2 , and the inlet position of the outlet vane in the radial direction is R 4 .
3. The centrifugal compressor according to claim 1, wherein the outlet vane is arranged so as to satisfy a relationship of 1.5 ≦ R 4 / R 2 ≦ 1.7.
【請求項4】 上記ディフューザの半径方向の長さをL
としたとき、その半径方向外側端の位置から0以上L/
10以下の位置に上記出口ベーンの出口が位置される請
求項1又は2記載の遠心圧縮機。
4. The radial length of the diffuser is L
From the position of the radially outer end, L / L
3. The centrifugal compressor according to claim 1, wherein the outlet of the outlet vane is located at 10 or less.
JP10235534A 1998-08-21 1998-08-21 Centrifugal compressor Pending JP2000064994A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10235534A JP2000064994A (en) 1998-08-21 1998-08-21 Centrifugal compressor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10235534A JP2000064994A (en) 1998-08-21 1998-08-21 Centrifugal compressor

Publications (1)

Publication Number Publication Date
JP2000064994A true JP2000064994A (en) 2000-03-03

Family

ID=16987410

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP2000064994A (en)

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EP3299634A4 (en) * 2015-10-29 2018-08-15 Mitsubishi Heavy Industries, Ltd. Scroll casing and centrifugal compressor
US10655637B2 (en) 2015-10-29 2020-05-19 Mitsubishi Heavy Industries, Ltd. Scroll casing and centrifugal compressor
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