JPS6098198A - Impeller - Google Patents

Abstract

PURPOSE:To prevent occurrence of the surging phenomenon which occurs earlier on the side remote from a core plate, by changing the blade outlet angle of blades of the impeller of a compressor of centrifugal type, mixed flow type or the like, widthwise of the blade so that the shift between the angle of the vane inlet and the angle of the inlet flow at the diffuser is eliminated. CONSTITUTION:An impeller comprises a core plate 1, a plurality of badles 2, an end plate 3 and a diffuser provided with vanes 4 in the outlet section of the impeller. As to the impeller having a wide blade width so that a specific speed is high widthwise of the blades 2 or in the outlet in the direction from the core plate side 1 to the side plate 3, there occures a more possible risk of deffects in the speed, resulting in variations in the actual angle of outlet flow which is therefore shifted from the inlet angle of the vane 4. Therefore, the more the position advanced to the side plate 3 from the core plate 1, the outlet angle of the blades 2 are made larger to eliminate the shift between the angle of outlet flow in the blade widthwise direction and the inlet angle of the vanes 4. Thus, earlier surging on the side plate 3 side is prevented from occurring, thereby the impeller having a high degree of efficiency may be obtained.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、羽根車に係り、特に高効率化に適した比速度
の大きな遠心式または斜流式の羽根車に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an impeller, and particularly to a centrifugal or mixed flow impeller with a large specific speed suitable for high efficiency.

〔発明の背景〕[Background of the invention]

遠心圧縮機、斜流圧縮様等の流体機械の羽根車は、高効
率化を狙って比速度が大きくなるにつれ、羽根車の内径
と外径の比が大きくなり、羽根中も広くなる。In the impellers of fluid machines such as centrifugal compressors and mixed flow compressors, as the specific speed increases with the aim of increasing efficiency, the ratio of the inner diameter to the outer diameter of the impeller increases, and the inside of the blade also becomes wider.

まず、従来の遠心式羽根車について、第１〜４図を参照
して説明する。First, a conventional centrifugal impeller will be explained with reference to FIGS. 1 to 4.

第１図は、一般的な遠心羽根車とベーン付きディフュー
ザの子牛断面図、第２図は第１図のＡ−Ａ断面図、第３
図は、従来の遠心羽根車の出口流れ速度三角形を示す線
図、第４図は、第３図の絶対流れ角αヨの羽根卓出ｌコ
ｒｌＪ方向の分布を示す線図である。Figure 1 is a cross-sectional view of a general centrifugal impeller and a diffuser with vanes, Figure 2 is a cross-sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view of a general centrifugal impeller and a diffuser with vanes.
The figure is a diagram showing the exit flow velocity triangle of a conventional centrifugal impeller, and FIG. 4 is a diagram showing the distribution of the absolute flow angle α y in the blade output direction L C R R J direction of FIG. 3.

第１図において、ｌは各板、２は羽根で、羽根車円周で
複数枚設けられている。３は側板で、これら各板ｌ、羽
根２、側板３で羽根車が形成されている。In FIG. 1, 1 is each plate, 2 is a blade, and a plurality of blades are provided around the circumference of the impeller. Reference numeral 3 denotes a side plate, and the plates 1, blades 2, and side plate 3 form an impeller.

第２図に示すように、羽根車出口における、羽根２と羽
根車の半径方向とのなす角度β（以下羽根出口角という
）は、必要とされる圧力係数の大きさに応じて、０°か
ら６０”てぃどの値がとられている。As shown in Fig. 2, the angle β between the blade 2 and the radial direction of the impeller at the impeller exit (hereinafter referred to as the blade exit angle) is 0° depending on the required pressure coefficient. The value is taken from 60”.

羽根出口角βは、通常は加工性などの点から、側板３側
から各板１側にかけて一定の値とするようにしている。The blade exit angle β is usually set to a constant value from the side plate 3 side to each plate 1 side from the viewpoint of workability.

また、このような羽根車を図示しないケーシングに収納
した高効率を要求される圧縮機などでは、静圧に回復さ
ぜるために、第１図に示すようなベーン４を備えたベー
ンイ１きデイフーザをケーシングに設けることが太い。In addition, in compressors that require high efficiency and have such an impeller housed in a casing (not shown), a vane 1 equipped with vanes 4 as shown in Fig. 1 is used to restore static pressure. It is important to provide a day fuser in the casing.

この場合、ベーンの入口と羽根車の半径方向とのなす角
度（以下ベーン入口角という）は、羽根車を出た流体の
流れの角度（以下ベーン入口流］を角ともいう）に合わ
せて設３１される。こｔシら羽根車出口における流れの
状態を第３図の速度三角形に示す。In this case, the angle between the vane inlet and the radial direction of the impeller (hereinafter referred to as vane inlet angle) is set in accordance with the angle of the flow of fluid exiting the impeller (hereinafter referred to as vane inlet flow). 31. The flow state at the impeller outlet is shown by the velocity triangle in FIG.

第３図において、原点Ｏは羽根車出口である。In FIG. 3, the origin O is the impeller outlet.

実線矢印ｕ２および破線矢印ｕ′２は羽根車周速、実線
矢印ｖ２は各板１側の羽根車出口絶対流れ方向における
流れ速度、破線矢印ｖ′２は側板３側の羽根卓出］コ絶
対流」を方向における流れ速度、実線矢印ｗ２は各板１
側の羽根車出口相対流れ方向における流れ速度、破線矢
印ｗ′２は側板３側の羽根口出１」相対流れ方向におけ
る流れ速度である。図において羽根車の半径方向とｖ２
とのなす角α３は羽根車出口絶対流れ角、すなわち、ベ
ーン入口流れ角１羽根車の半径方向とｗ２とのなす角α
′３は羽根車出口相対流れ角である。The solid line arrow u2 and the broken line arrow u'2 are the circumferential speed of the impeller, the solid line arrow v2 is the flow velocity in the absolute flow direction at the impeller outlet on each plate 1 side, and the broken line arrow v'2 is the blade output on the side plate 3 side] absolute Flow velocity in the direction of ``flow'', solid line arrow w2 indicates each plate 1
The flow velocity in the flow direction relative to the side impeller outlet, the dashed arrow w'2 is the flow velocity in the flow direction relative to the impeller outlet 1'' on the side plate 3 side. In the figure, the radial direction of the impeller and v2
The angle α3 formed by the impeller exit is the absolute flow angle at the impeller exit, that is, the angle α between the vane inlet flow angle 1 and the radial direction of the impeller and w2.
'3 is the relative flow angle at the impeller outlet.

羽根車出口相対流れ角α′３は、すべりのために羽根出
口角βよりやや大きな角度になる。ベーン入口角は、ベ
ーン入口流れ角α３ど同じが、やや大きい角度に改削さ
れる。The impeller exit relative flow angle α'3 becomes a slightly larger angle than the blade exit angle β due to slippage. The vane inlet angle is the same as the vane inlet flow angle α3, but has been revised to a slightly larger angle.

このような設８１法は、羽根車出口流れ角、すなほちベ
ーン入口流れ角α３が、側ｖｉ３側から各板ｌ側まで一
定であれば、ベーン入口角に対し適正な流れとなり効率
も高く、作動範囲も広くなることが期待できる。しかし
、羽根車の内径と外径の比が大きく、羽根＋ｌＪの広い
比速度の大きな羽根車においては、側板３側で速度欠陥
が生しるため、第３図の破線で示すｖ′２のように、ベ
ーン人口流れ角α３が大きくなり、ベーン人１」角との
間にずれを生じる。In this setting method, if the impeller outlet flow angle and the flat vane inlet flow angle α3 are constant from side vi3 to each plate l side, the flow will be appropriate for the vane inlet angle and the efficiency will be high. , it can be expected that the operating range will become wider. However, in an impeller with a large ratio of the inner diameter to the outer diameter of the impeller and a large specific speed of the blades +lJ, a speed defect occurs on the side plate 3 side, so that the value of v'2 shown by the broken line in FIG. As a result, the Vane population flow angle α3 increases, causing a deviation from the Vane population flow angle α3.

このような状態になると、設計仕様の流量においても、
羽根車出口流］し角α′３は、第４図の線図に示すよう
な分布が生じ、ベーン入口角に対し適正なベーン入に１
流才し角となっている部分が狭くなるため、効率低下を
きたすとともに、側板側でもつともベーン人１−」角と
のずれが大きいため、側板３側か心板Ｊ側より〒、くサ
ージング曳糸を生じ、結果どしで、圧縮機の作動範囲が
狭くなるという欠点がある。In such a situation, even at the design specification flow rate,
The impeller exit flow] angle α'3 has a distribution as shown in the diagram in Fig.
Because the part that is the flowing angle becomes narrower, efficiency decreases, and since there is a large deviation from the Vane angle on the side plate side, the side plate side 3 side or the core plate J side is surged. This has the disadvantage of creating stringiness, which in turn reduces the operating range of the compressor.

〔発明の目的〕[Purpose of the invention]

本発明は、前述の従来技術の問題六１、（に焦みなされ
たものＣ１羽根巾出し」の流路１１Ｊ全体にわたってベ
ーン人［」流Ｊし角が、ディユーザーのヘーン入口角に
列し適正な角度となる羽根車を提（，１（シ、流体機械
の効率と作動範囲を高めるｍ−と“を、その目的として
いる。The present invention solves the above-mentioned problem 61 of the prior art. Its purpose is to provide an impeller with an appropriate angle to increase the efficiency and operating range of fluid machinery.

〔発明の慨要〕[Summary of the invention]

本発明に係る羽根ｊｊｉの溝底は、少なくとも各板およ
び腹数枚の羽根からなる羽根車において、当該羽根車の
出口にお（ブる、前記羽根の羽恨面が前記羽根車の半径
方向となす羽根出口角度を、羽根の合板側でｔＪｒさく
各板から遠ざかるにつれて大きくなるように形成したも
のである。In an impeller consisting of at least each plate and several blades, the groove bottom of the blade jji according to the present invention is located at the outlet of the impeller (the groove bottom of the blade is located in the radial direction of the impeller). The blade exit angle tJr is formed on the plywood side of the blade and increases as the distance from each plate increases.

〔発明の実施例〕[Embodiments of the invention]

以下、本発明の一実施例を第５図ないし第８図を参照し
て説明する。Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 5 to 8.

第５図は、本発明の一実施例に係る遠心羽根車とベーン
付きディフューザの子牛断面図、第６図は、第５図のＢ
　−Ｆ３断面図、第７図は、羽根出し１角度の羽根車出
口方向の分布を示す線図、第８図は、本発明の一実施例
に係る遠心羽根車の出１」流れ速度三角形を示す線図で
ある。各図において、先の第１〜第４図と同一符号のも
のは従来技術と同等部分゛Ｃあるから、その説明を省略
する。FIG. 5 is a calf sectional view of a centrifugal impeller and a diffuser with vanes according to an embodiment of the present invention, and FIG.
-F3 cross-sectional view, FIG. 7 is a diagram showing the distribution in the impeller exit direction at one angle of blade extension, and FIG. 8 is a diagram showing the flow velocity triangle of the centrifugal impeller according to an embodiment of the present invention. FIG. In each figure, the same reference numerals as those in FIGS. 1 to 4 are the same parts as in the prior art, so the explanation thereof will be omitted.

第５図において、Ｘは、各板１から側板３へ軸方向にｆ
ｌ＋！１つだ羽根卓出口の距離Ｃある。In FIG. 5, X is f in the axial direction from each plate 1 to the side plate 3.
l+! There is one blade table exit distance C.

第７図の線図は、横軸に各板から側板への距離Ｘをとり
、縦軸に羽根出１」角βをとっている。本実施例では、
羽根出し１角βを、合板ｊ側で小ごく、ル）板から遠ざ
かるにつれて大きく、側板３側で大きくなるよう形成し
ている。In the diagram of FIG. 7, the horizontal axis represents the distance X from each plate to the side plate, and the vertical axis represents the blade projection angle β. In this example,
The blade extension angle β is small on the plywood j side, becomes large as it moves away from the plywood board, and becomes large on the side plate 3 side.

このような羽根車の出口における流体の流れの状態を第
８図の速度三角形に示す。The state of fluid flow at the outlet of such an impeller is shown by the velocity triangle in FIG.

第８図において、実線は心根１側の羽根車出口０での速
度三角形、破線は側板３側の羽根車出口Ｏ′での速度三
角形である。In FIG. 8, the solid line is the velocity triangle at the impeller outlet 0 on the core root 1 side, and the broken line is the velocity triangle at the impeller outlet O' on the side plate 3 side.

実線矢印ｖ２は心根ｌ側の羽根卓出１」羅列流れ方向に
おける流れ速度、破線矢印ｖ′２は側板３８Ｎ！Ｉの羽
根「１（出「」絶対流れ方向における流Ａし速度、実線
矢印Ｗ２は心根１側の羽根卓出１」相対流イ′シ方向に
おける流２し速度、破線矢印ｗ′２ば側板３側の羽根卓
出［」相対流れ方向における流産し速度℃・ある。The solid line arrow v2 indicates the flow velocity in the flow direction of the blades on the core root l side, and the broken line arrow v'2 indicates the side plate 38N! The flow A speed in the absolute flow direction of the blade I "1 (exit"), the solid line arrow W2 is the flow A speed in the relative flow I' direction, the solid line arrow W2 is the flow 2 speed in the relative flow I' direction, the dashed line arrow W'2 is the side plate The blades on the third side have a miscarriage velocity in the relative flow direction [°C].

側板側羽根卓出１」で羽根出口角βを大きく噌ることに
より、側板側の羽根車出口相対流れ角α′３は右板側の
羽根車出口相対流れ角より大きくなり、速度三角形は第
８図の破線で示づ−ようになる。したがって羽根出口角
度’ｂ’＋Ｅ　Ａ”一方向を側１反側と右板側とほぼ同
じに４−ることかできる。ずなわち心根１側と側板３側
とのベーン人１コ１流れ角（羅列流れ角）αヨがほぼ同
じになるので　ティノユーザベーン４のベーン入１」角
とのすＡしがなくなる。By increasing the blade outlet angle β with the blade angle 1 on the side plate side, the relative flow angle α'3 at the impeller outlet on the side plate side becomes larger than the relative flow angle at the impeller outlet on the right plate side, and the speed triangle becomes The result is as shown by the broken line in Figure 8. Therefore, the blade exit angle 'b' + E A'' can be made in one direction to be approximately the same as the opposite side of side 1 and the right plate side.In other words, one vane person and one flow between the core root 1 side and the side plate 3 side. Since the angles (flow angles) α and y are almost the same, there is no difference between the vane-included angle of Tino-User Vane 4 and the angle of A.

本実施例によれは、羽根東出口におりるベーン入１」流
れ角、釘なわち絶対流れ角αヨを、側板３側から右板側
１にかけて一様にすることができるので、股引流量にお
いては、流体流れのディフューザ・ベーンに対する衝突
損失を減することができ、効率を向上させることになる
。また、非設Ｈ１流足においても、流星＋ｌｊ全域にわ
たって、羽根車出口相対流Ｊし角α３が一様であるこ−
とから、側板３側で早くサージングに入ることを防ぐこ
とにより、流体機械の作動範囲を広くすることが可能と
なる。According to this embodiment, the flow angle of the vane entering the vane at the east exit of the vane, that is, the absolute flow angle α yo, can be made uniform from the side plate 3 side to the right plate side 1, so the crotch pulling flow rate can be made uniform. In this case, impingement losses of the fluid flow to the diffuser vanes can be reduced, resulting in improved efficiency. In addition, even in the non-installed H1 flow foot, the impeller exit relative flow angle α3 is uniform over the entire meteor +lj region.
Therefore, by preventing early surging on the side plate 3 side, it is possible to widen the operating range of the fluid machine.

なお、前記実施例においては、側板イ」きの遠心羽根車
の例を説明したが、本発明は側板付きの羽根車に限るも
のではなく、側板無しの羽根車に対しても同様の効果が
期待できるものである。In the above embodiments, an example of a centrifugal impeller with side plates has been described, but the present invention is not limited to impellers with side plates, and similar effects can be obtained on impellers without side plates. This is something to look forward to.

また、本発明は、遠心羽根車に限らず、斜流式の羽根車
にも適応できるものである。Furthermore, the present invention is applicable not only to centrifugal impellers but also to mixed flow type impellers.

〔発明の効果〕〔Effect of the invention〕

以上述べたように、本発明によれば、羽根車出口の流路
１１Ｊ全体にわたって、ベーン人ロ流！シ角が、ディフ
ューザのベーン入口角に対し適正となる羽根車を提供で
き、当該羽根車を適用する流体機械の効率と作動範囲を
高めることができる。As described above, according to the present invention, the entire flow path 11J at the impeller outlet is flown in a vane style! It is possible to provide an impeller whose angle is appropriate for the vane inlet angle of the diffuser, and it is possible to improve the efficiency and operating range of a fluid machine to which the impeller is applied.

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

第１図は、一般的な遠心羽根車とベーン付きディフュー
ザの子午断面図、第２図は、第１図のＡ−Ａ断面図、第
３図は、従来の遠心羽根車の出口流れ速度二角形を示を
線ｌｂ！、第４図は、第３図の絶対流れ角の羽根卓出Ｌ
：ｌｌ　１１１方向のイ）布を示す線図、第５図は、本
発明の一実施例に係る遠心羽根車どベーン伺きディフュ
ーザの子午〜１面図、第６図は、第５図の１３−Ｂ断面
図、第７図は、羽根出口角度の羽根出［」角度の羽イｊ
Ｊ車出ｒｌ　Ｉｌｊ、／Ｊ向のづ）布を示すｌｆ：！、
回、第８０目、本発明の一某ＪＪ＆例に係る遠心調相、
Ｉの呂「１流れ速度三角形４示す線図である。 ｆＪＩ　図 第Ｚ図 猶　３　図 第４図 第５　図　ｒｆＪｌ　図 第７　口Figure 1 is a meridional cross-sectional view of a typical centrifugal impeller and a diffuser with vanes, Figure 2 is a cross-sectional view taken along line A-A in Figure 1, and Figure 3 is a diagram showing the exit flow velocity of a conventional centrifugal impeller. Line lb indicates a square! , Figure 4 shows the absolute flow angle of the blade L in Figure 3.
Figure 5 is a meridian-first view of a centrifugal impeller and vane diffuser according to an embodiment of the present invention, and Figure 6 is a diagram showing the cloth in the 111 direction. 13-B sectional view, Fig. 7 shows the blade exit angle of the blade exit angle.
J car exit rl Ilj, /J direction) lf showing cloth:! ,
No. 80, Centrifugal phase modulation according to a certain JJ & example of the present invention,
This is a diagram showing flow velocity triangle 4.

Claims (1)

【特許請求の範囲】 ■、少なくとも各板および複数枚の羽根からなる羽根車
において、当該羽根車の出口にお【ブる、前記羽根の羽
根面が前記羽根車の半径方向となす羽根出口角度を、羽
根の各板側で小さく各板から遠ざかるにつれて大きくな
るように形成したことを特徴とする羽根車。[Scope of Claims] (1) In an impeller consisting of at least each plate and a plurality of blades, the blade exit angle formed by the blade surface of the blade with the radial direction of the impeller; An impeller characterized in that the impeller is formed such that it is small on each plate side of the blade and becomes larger as it moves away from each plate.