JP3817625B2 - Burner equipment - Google Patents

Description

【００４８】
本実施の形態では、点火後にパイロットノズル孔４６の燃料ガスの供給を停止しているけれども、これに限定されるものではなく、点火後も常時パイロットノズル孔４６へ燃料ガスを供給して燃焼するようにしてもよい。また燃料ガスを外流路４７に導くガス導入孔５０は、内筒体１０の内突起３４に形成されているけれども、管状体を内筒体１０の内周面に設けるように構成してもよい。また主ノズル孔４８およびガス導入孔５０の軸線は、同一であり、内筒体１０の軸線１０ａを含む仮想平面内に存在するように構成されているけれども、アウタスワラ４０からの空気の旋回流に沿って仮想平面に対して交差するように傾斜させてもよい。
【００４９】
図８は、本発明の他の実施の形態であるバーナ装置の主要部の構成を簡略化して示す断面図である。本実施の形態のバーナ装置６５の構成は、図１〜３に示すバーナ装置１の構成と類似し、対応する部分には同一の参照符号を付して説明を省略する。注目すべきは、仕切筒体６６の上流側一端部の外径が絞られており、その他の部分の外径よりも小さくなるように形成されている点である。これによって、第２流路５５に流入する空気流量が減少するので、ガス導入孔５０を介して外流路４７に流入する燃料ガス流量が少ないとき、燃料ガスの主流路となる第２流路５５内において少ない燃料ガスとそれに見合う減少した空気とを混合させることができる。したがって混合ガスの当量比が燃焼可能範囲よりも過小になることが防止され、燃焼火炎の消炎を防止することができる。その結果、混合ガスを安定して燃焼させることができ、燃料ガスを完全燃焼させることが可能となる。
【００５０】
図９は、本発明のさらに他の実施の形態であるバーナ装置の主要部の構成を簡略化して示す断面図である。本実施の形態のバーナ装置６８の構成は、前記バーナ装置１の構成と類似し、対応する部分には同一の参照符号を付して説明を省略する。注目すべきは、本実施の形態では仕切筒体が３個設けられている点である。第１〜第３仕切筒体６９，７０，７１は、内筒体１０と外筒体１２との間に内側からこの順序で設けられ、外流路４７を４つに仕切って第２〜第５流路５５，５６，７３，７４を内側からこの順序で規定する。また各流路の断面積は、外側になるほど大きくなるように形成されており、第５流路７４の断面積が最も大きい。このため、外側の流路になるほど供給される空気流量が多くなる。
【００５１】
第３仕切筒体７１の一端部は、主ノズル孔４８の軸線４９よりも下流側にずらして取付けられている。前記ずれの大きさは、前記軸線４９と第３仕切筒体７１の延長との交点をＰとすると、交点Ｐから第３仕切筒体７１の一端部までの距離Ｌ３によって表される。前記ずれの大きさＬ３の第３仕切筒体７１の全長Ｌ４に対する比率Ｒ１（＝Ｌ３／Ｌ４×１００）は、前記バーナ装置１の場合と同様に０≦Ｒ１≦８０％の範囲の値であることが好ましく、５％≦Ｒ１≦５０％の範囲であることが特に好ましい。第１および第２仕切筒体６９，７０のガス流れ方向設置位置および全長は第３仕切筒体７１と同一である。
【００５２】
ガス導入孔５０を介して外流路４７に流入した燃料ガスは、流入量が少ないときには第２流路５５に主として流入し、流入量が増大するにつれて順次外側の流路に主として流入する。これによって、本実施の形態では前記バーナ装置１に比べてさらにきめ細かく主流入流路を切換えることができるので、各流路に供給される空気流量に見合った燃料ガスを流入させることができ、各流路における混合ガスの当量比は燃焼可能範囲よりも過小になることがさらに確実に防止される。
【００５３】
以上述べたように、本発明はガスタービンの燃焼器のバーナ装置として好適に用いることができる。しかしながら、本発明の用途はガスタービンのみに限定されるものではなく加熱炉のバーナ装置など広範囲な用途に好適に用いることが可能である。
【００５４】
実施例
本発明のバーナ装置の効果を確認するために、実施例として図１〜図３に示すバーナ装置１を用いて燃料ガスの燃焼実験を行った。用いたバーナ装置１における各部材の寸法などは表２に示す通りであった。内筒体１０の内突起３４の傾斜部３４ｂと、ノズル体２０の中間テーパ部３３との間隙３９は０．５ｍｍに設定した。仕切筒体５４の一端部と、主ノズル孔４８の軸線４９とのずれＬ２の仕切筒体５４の長さＬ１に対する比率Ｒ（＝Ｌ２／Ｌ１×１００）は１０％に設定した。これに対して比較例として、仕切筒体を省略した点を除いて実施例と同一の構成を有するバーナ装置を用いて燃料ガスの燃焼実験を行った。
【００５５】
【表２】

【００５６】
このようなバーナ装置を用いた燃焼実験では、空気流路８を介して温度３５０℃の空気を流量７００Ｎｍ³ ／ｈで供給した。供給された空気は、第１流路４５、外流路４７および燃焼筒１４の外側の流路５１を介して下流側に流れた。この燃焼筒１４の外側の流路５１を流れる空気は、燃焼筒１４の空気孔５２を介して燃焼筒１４内に流入した。燃料ガスとしてメタンを用い、流量１Ｎｍ³／ｈでノズル体２０のパイロットノズル孔から噴出させるとともに、流量２４．７Ｎｍ³／ｈでノズル体２０の主ノズル孔から噴出させた。供給した空気とメタンとを混合して混合ガスとし、点火プラグ５８で点火させて混合ガスを燃焼させて燃焼ガスを生成した。点火後、パイロットノズル孔４６からのメタンの噴出を停止し、主ノズル孔４８から噴出されるメタンの噴出流量を２５．７Ｎｍ³／ｈにした。このときの混合ガスの当量比は０．３５であった。その後メタン供給量を漸減して、換言すれば当量比を漸減して燃焼状態の変化を調べた。燃焼状態の評価は、燃焼効率と排出ガス中のＮＯｘ含有率で行った。その結果を図１０および図１１に示す。
【００５７】
図１０は混合ガスの当量比と燃焼効率との関係を示すグラフであり、図１１は混合ガスの当量比と排ガス中のＮＯｘ含有率との関係を示すグラフである。燃焼効率は、混合ガス中の燃料ガスの完全燃焼の程度を表す指標であり、排ガス中の不完全燃焼生成物であるＣＯおよびＨＣの含有率（％）を測定することによって算出される。これらの成分は、燃焼火炎の消炎などによって不完全燃焼が生じていることを表す。したがって、排ガス中にＣＯおよびＨＣが含まれないとき燃焼効率は１００％となる。図１０および図１１中において、実施例の実験結果を参照符７５で表し、比較例の実験結果を参照符７６で表す。図１０中における参照符７７は、実施例の第１流路４５に燃料ガスが主として流入する当量比範囲を表しており、参照符７８は実施例の第２流路５５に燃料ガスが主として流入する当量比範囲を表しており、参照符７９は実施例の第３流路５６に燃料ガスが主として流入する当量比範囲を表している。また図１０中における参照符８０は、比較例の第１流路すなわち内筒体１０内に燃料ガスが主として流入する当量比範囲を表しており、参照符８１は比較例の第２流路すなわち外流路に燃料ガスが主として流入する当量比範囲を表している。
【００５８】
図１０から、当量比０．３０〜０．３５の範囲では実施例７５および比較例７６とも燃焼効率が１００％であること、当量比０．３０未満では実施例および比較例とも当量比が低くなるほど燃焼効率が低下すること、実施例７５は比較例７６に比べて当量比の低下に対する燃焼効率の低下度合いが小さいこと、したがって同一の当量比で比較すると実施例７５は比較例７６に比べて燃焼効率が良好であること、この傾向は特に当量比０．１〜０．２５において、すなわち実施例のバーナ装置１の第２流路５５に主として燃料ガスが流入しているときに顕著であることなどが判る。また図１１から、排ガス中のＮＯｘ含有率は実施例７５および比較例７６ともほぼ同一であること、排ガス中のＮＯｘ含有率はともに低水準であることなどが判る。このように実施例のバーナ装置１は、当量比を低くしてもすなわちメタンの供給量を少なくしても低ＮＯｘ性を保ったまま良好な燃焼効率を維持することができる。
【００５９】
【発明の効果】
以上のように請求項１記載の本発明によれば、主ノズル孔からの燃料ガスの噴出量が少ないとき、燃料ガスが空気流入量の少ない内流路に主に流入するので、混合ガスの当量比が燃焼可能範囲よりも過小になることが防止され、燃焼火炎は消炎することなく安定的に燃焼を続けることができる。また外流路に流入する燃料ガスの流入量の増減につれて燃料ガスの主に流入する流路が切換わるので、各流路における混合ガスの当量比が適正に保たれる。これによって、外流路に流入する燃料ガスの流量が少ないときでも当量比が燃焼可能範囲よりも過小になることが防止されるので、外流路における燃焼火炎の消炎が防止される。したがって、燃料ガスの供給流量にかかわらず、混合ガスを安定して燃焼させることができ、燃料ガスの不完全燃焼を防止することができる。
【００６０】
また請求項２記載の本発明によれば、主ノズル孔およびガス導入孔の軸線は共通の一直線上に存在し、ガス導入孔の内径は主ノズル孔の内径よりも大きく、かつ前記主ノズル孔の軸線と内筒体の軸線とのなす角度が適正に設定されているので、主ノズル孔から噴出された燃料ガスは、噴出量が多いとき確実にガス導入孔に導かれ外流路に流入することができる。
【００６１】
また請求項３記載の本発明によれば、仕切筒体の一端部は前記主ノズル孔の軸線よりも下流側にずらして取付けられており、かつずれの大きさが適正に設定されているので、外流路に流入した燃料ガスを流入量に応じて所望の流路に確実に導くことができる。
【００６２】
また請求項４記載の本発明によれば、仕切筒体の一端部の外径はそれ以外の部分の外径よりも小さく設定されているので、外流路の内側の流路における入側断面積が小さくなり、外流路の内側の流路に流入する空気量を減少させることができる。また外流路に流入する燃料ガスの流入量が少ないとき、流入した燃料ガスは外流路の内側の流路に流入するので、外流路の内側の流路では燃料ガスの流入量と空気量とが見合い、混合ガスの当量比が燃焼可能範囲よりも過小になることが防止される。
【００６３】
また請求項５記載の本発明によれば、内流路の空気の流速は、外流路の空気の流速よりも低速である。また内流路に流入する空気流量は、外流路に流入する空気流量よりも小流量である。したがって、内流路に流入する燃料ガスの流量が少ないときでも、混合ガスの当量比が燃焼可能範囲よりも過小になることが防止され、内流路における燃焼火炎の消炎が防止される。
【００６４】
また請求項６記載の本発明によれば、仕切筒体が半径方向に間隔をあけて複数同軸に設けられているのでガス導入孔を介して外流路に流入した燃料ガスは流入量が少ないときには最も内側の流路に主として流入し、流入量が増大するにつれて順次外側の流路に主として流入する。また複数の仕切筒体によって仕切られる各流路の断面積が半径方向外方になるほど大きくなるように設定されているので、外側の流路に供給される空気流量は内側の流路に供給される空気流路よりも多くなる。これによって、きめ細かく主流入流路を切換えることができるとともに、各流路に供給される空気流量に見合った燃料ガスを流入させることができる。したがって、各流路における混合ガスの当量比が燃焼可能範囲よりも過小になることが確実に防止される。
【図面の簡単な説明】
【図１】本発明の実施の一形態であるバーナ装置の主要部の構成を簡略化して示す断面図である。
【図２】図１に示すバーナ装置の全体構成を簡略化して示す断面図である。
【図３】図１に示すバーナ装置の主要部を拡大して示す断面図である。
【図４】図３の切断面線ＩＶ−ＩＶから見た断面図である。
【図５】図４からノズル体を取外した状態の断面図である。
【図６】インナスワラの構成を簡略化して示す斜視図である。
【図７】ガスタービンに対するバーナ装置の配置状況を示す斜視図である。
【図８】本発明の他の実施の形態であるバーナ装置の主要部の構成を簡略化して示す断面図である。
【図９】本発明のさらに他の実施の形態であるバーナ装置の主要部の構成を簡略化して示す断面図である。
【図１０】混合ガスの当量比と燃焼効率との関係を示すグラフである。
【図１１】混合ガスの当量比と排ガス中のＮＯｘ含有率との関係を示すグラフである。
【符号の説明】
１，６５，６８ バーナ装置
８ 空気流路
１０ 内筒体
１２ 外筒体
１４ 燃焼筒
２０ ノズル体
２７ ガス供給装置
２９ 流量制御弁
３４ 内突起
３６ インナスワラ
４０ アウタスワラ
４５ 第１流路
４６ パイロットノズル孔
４７ 外流路
４８ 主ノズル孔
５０ ガス導入孔
５２ 空気孔
５４ 仕切筒体
５５ 第２流路
５６ 第３流路
５８ 点火プラグ
６０ 導出筒[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a burner device for burning fuel gas that is preferably used in a gas turbine, a heating furnace, and the like.
[0002]
[Prior art]
Various cogeneration systems have been proposed and put into practical use for local power generation, district heating, and the like. One typical system of such a cogeneration system includes a burner device for burning fuel gas, and a gas turbine that is rotationally driven by the combustion gas combusted by the burner device, and rotates the gas turbine. Electricity is generated using it.
[0003]
The burner apparatus in such a cogeneration system includes a primary nozzle means to which the fuel gas from the first gas supply means is supplied, and a secondary nozzle means to which the fuel gas from the second gas supply means is supplied. There is something with. The primary nozzle means defines a first flow path, and the fuel gas from the first gas supply means is ejected into the air flow flowing through the first flow path, thereby generating a combustible mixed gas. The secondary nozzle means defines a second flow path, and the fuel gas from the second gas supply means is ejected into the air flow flowing through the second flow path, so that the mixed gas of the primary nozzle means is larger. A combustible gas mixture with a low gas concentration is produced. In such a burner apparatus, since the gas concentration of the mixed gas of the primary nozzle means is higher than the gas concentration of the mixed gas of the secondary nozzle means, the mixed gas of the primary nozzle means is burned, and the primary nozzle means The mixed gas of the secondary nozzle means is burned using the combustion gas. By burning the fuel gas in this manner, lean combustion becomes possible, and the combustion temperature of the combustion gas can be lowered, thereby enabling highly efficient combustion with reduced generation of nitrogen oxides (NOx). .
[0004]
[Problems to be solved by the invention]
In such a burner device, the combustion output of the burner device is controlled by controlling the amount of fuel gas ejected into the second flow path. If the amount of fuel gas jetted is reduced in order to reduce the combustion output, the air is excessive with respect to the fuel gas and the combustion flame from the secondary nozzle means disappears, or the fuel gas jetting control cannot be followed. Therefore, at a low load, there is a problem that the combustion state of the secondary nozzle means becomes unstable and incomplete combustion tends to occur.
[0005]
Further, if the combustion flame from the secondary nozzle means is extinguished or burned while burning the fuel gas from the primary nozzle means, the temperature fluctuation of the combustion gas is caused, and the load fluctuation is caused in the gas turbine to which this combustion gas is fed. Cause.
[0006]
The objective of this invention is providing the burner apparatus which can burn fuel gas stably irrespective of the supply flow rate of fuel gas, and can burn fuel gas completely.
[0007]
[Means for Solving the Problems]
The present invention , A nozzle body having a main nozzle hole for ejecting fuel gas and a pilot nozzle hole;
An inner cylinder that surrounds the nozzle body and defines an inner flow path, and an introduction flow path that is connected to the inner flow path is defined between the nozzle body and the inner cylinder, An inner cylinder in which a gas introduction flow hole is formed on the peripheral wall of the cylinder so as to face the main nozzle hole and sandwich the introduction flow path;
An outer cylinder that is provided radially outwardly of the inner cylinder and that defines an outer flow path; and
Provided between the inner cylinder and the outer cylinder, One end portion on the upstream side in the gas flow direction is provided on the downstream side in the gas flow direction with respect to the axis of the main nozzle hole and the gas introduction hole, and a cylindrical shape that divides the outer flow path into a plurality of flow paths in the radial direction A partition cylinder;
Gas supply means for supplying fuel gas to the nozzle body;
An air supply means for supplying air to the introduction flow path and the external flow path.
[0008]
According to the present invention, the inner cylinder that defines the inner flow path is provided so as to surround the nozzle body, and an introduction flow path that is connected to the inner flow path is formed between the inner cylinder and the nozzle body, Air is supplied to the introduction channel and the outer channel. Since the introduction channel is formed in the gap between the inner cylinder and the nozzle body, the cross-sectional area is smaller than that of the outer channel, and the air flow rate flowing into the inner channel via the introduction channel is smaller than that of the outer channel. . Further, since the main nozzle hole and the gas introduction hole are provided to face each other across the introduction flow path, the fuel gas is ejected from the main nozzle hole toward the gas introduction hole via the introduction flow path. As a result, when the amount of fuel gas ejected from the main nozzle hole is small, that is, when the fuel gas ejection speed is low, the fuel gas from the main nozzle hole is subjected to the action of the airflow flowing through the introduction flow path and is combined with the airflow. It flows toward the inner flow path on the downstream side in the gas flow direction. When the amount of fuel gas ejected from the main nozzle hole increases, that is, when the fuel gas ejection speed increases, the fuel gas from the main nozzle hole overcomes the air flow flowing through the introduction channel and crosses the introduction channel. It flows into the gas introduction hole and flows toward the outer flow path. When the amount of inflow is small, the fuel gas that has flowed into the outer channel mainly flows into the inner channel partitioned by the partition cylinder, and when the amount of inflow increases, the fuel gas mainly flows into the outer channel. In this way, when the amount of fuel gas ejected from the main nozzle hole is small, the fuel gas mainly flows into the inner flow path with a small amount of air inflow, so the equivalence ratio of the mixed gas (reciprocal of the air ratio) can be burned. The combustion flame can be stably burned without being extinguished. Further, as the flow rate of the fuel gas flowing into the outer flow path is increased or decreased, the flow path where the fuel gas mainly flows is switched, so that the air supply amount corresponding to the flow rate of the fuel gas can be obtained with the cross-sectional area of each flow path. If set to, the equivalence ratio of the mixed gas is maintained properly. As a result, even when the flow rate of the fuel gas flowing into the outer flow path is small, the equivalence ratio is prevented from becoming smaller than the combustible range, so that the extinguishing of the combustion flame in the outer flow path is prevented. Therefore, the burner device of the present invention can burn in a stable combustion state regardless of the supply flow rate of the fuel gas, and can prevent incomplete combustion of the fuel gas.
[0009]
The axis of the main nozzle hole and the gas introduction hole of the present invention is present on a common straight line, the inner diameter of the gas introduction hole is larger than the inner diameter of the main nozzle hole, and the axis of the main nozzle hole and the inner cylinder The angle θ formed with the axis is a value in the range of 10 degrees ≦ θ ≦ 90 degrees.
[0010]
According to the present invention, the axes of the main nozzle hole and the gas introduction hole exist on a common straight line, the inner diameter of the gas introduction hole is larger than the inner diameter of the main nozzle hole, and the axis of the main nozzle hole and the inner cylindrical body Since the angle formed with the axis is appropriately set, the fuel gas ejected from the main nozzle hole can be reliably guided to the gas introduction hole and flow into the outer flow path when the discharge amount is large.
[0011]
Also, one end of the partition cylinder of the present invention on the upstream side in the fuel gas flow direction is attached to the downstream side of the axis of the main nozzle hole, and is attached to the entire length of the partition cylinder of the size of the deviation. The ratio R is a value in the range of 0 ≦ R ≦ 80%.
[0012]
According to the present invention, the one end portion of the partitioning cylinder is attached to be shifted downstream from the axis of the main nozzle hole, and the size of the deviation is set appropriately, so that it flows into the outer flow path. The fuel gas can be reliably guided to a desired flow path according to the inflow amount.
[0013]
Moreover, the outer diameter of the one end part of the said partition cylinder of this invention is smaller than the outer diameter of the other part, It is characterized by the above-mentioned.
[0014]
According to the present invention, since the outer diameter of the one end portion of the partitioning cylinder is narrowed to be smaller than the outer diameter of the other portion, the inlet side cross-sectional area in the inner channel of the outer channel becomes smaller, and the outer channel The amount of air flowing into the inner flow path can be reduced. Further, when the amount of fuel gas flowing into the outer flow path is small, the flow of fuel gas flows into the flow path inside the outer flow path due to the action of the air flow. The amount and the air amount are commensurate with each other, and the equivalent ratio of the mixed gas is prevented from becoming smaller than the combustible range.
[0015]
The flow rate of air in the outer flow path of the present invention is higher than the flow speed of air in the internal flow path.
[0016]
According to the present invention, the air flowing into the inner flow path is supplied via the introduction flow path, so that the air flow rate of the inner flow path is determined by the cross-sectional area of the inlet portion of the introduction flow path. Since the introduction flow path is formed between the nozzle body and the inner cylinder, the cross-sectional area of the inlet portion is small and smaller than the cross-sectional area of the inlet portion of the outer flow path. Therefore, the air flow rate flowing into the inner flow path is smaller than the air flow rate flowing into the outer flow path. In the inner flow path, air flows from the introduction flow path having a small cross-sectional area into the internal flow path having a relatively large cross-sectional area. Slower than the flow rate of air. As described above, since the flow velocity and flow rate of air in the inner flow path are lower than those in the outer flow path and smaller, the fuel gas and the air flow are reduced even when the flow rate of the fuel gas flowing into the inner flow path is small. The equivalence ratio of the mixed gas is prevented from becoming smaller than the combustible range, and the extinction of the combustion flame in the inner flow path is prevented.
[0017]
Further, the present invention is characterized in that a plurality of the partition cylinders are provided coaxially at intervals in the radial direction, and the cross-sectional area of each flow path partitioned by the plurality of partition cylinders is larger toward the outside in the radial direction. To do.
[0018]
According to the present invention, since the plurality of partition cylinders are provided coaxially at intervals in the radial direction, the amount of fuel gas that has flowed into the outer flow path through the gas introduction hole is reduced by the action of the air flow. It mainly flows into the innermost flow path, and mainly flows into the outer flow path sequentially as the amount of flow increases. In addition, since the cross-sectional area of each flow path partitioned by the plurality of partitioning cylinders is set so as to increase outward in the radial direction, the air flow rate supplied to the outer flow path is supplied to the inner flow path. More than the air flow. As a result, the main inflow channel can be finely switched, and fuel gas corresponding to the air flow rate supplied to each channel can be introduced. Therefore, it is reliably prevented that the equivalent ratio of the mixed gas in each flow path is smaller than the combustible range, and the extinction of the combustion flame is prevented.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view showing a simplified configuration of a main part of a burner apparatus according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a simplified overall configuration of the burner apparatus shown in FIG. . The burner device 1 includes a diffuser 2, and a cylindrical holding case 4 is attached to the diffuser 2 via a flange 5. A combustion case 6 is disposed in the holding case 4, and one end of the combustion case 6 is attached to the diffuser 2. An air passage 8 is formed in the diffuser 2, and combustion air is supplied to one end portion of the combustion case 6 through the air passage 8. Combustion air (hereinafter abbreviated as “air”) is supplied in a compressed state by an air compressor 9.
[0020]
An attachment support block 16 is attached to the diffuser 2, and one end of an external gas supply pipe 18 is attached to the attachment support block 16. A nozzle body 20 is attached to the other end of the outer gas supply pipe 18. A space 22 is formed inside the nozzle body 20, and a partition sleeve 24 is mounted through the internal space 22 in the axial direction. The internal space 22 is partitioned by a partition sleeve 24 into an inner first space 22a and an outer second space 22b of the first space 22a. The other end of the outer gas supply pipe 18 communicates with the second space 22 b of the injection nozzle body 20. An inner gas feed pipe 26 is disposed inside the outer gas feed pipe 18, one end of which is attached to the mounting support block 16, and the other end is attached to the nozzle body 20. The inner gas supply pipe 26 communicates with the first space 22 a of the nozzle body 20.
[0021]
A gas supply device 27 that is a gas supply means for supplying fuel gas is connected to the inner gas supply pipe 26 and the outer gas supply pipe 18. The gas supply device 27 includes a gas supply source 25 in which fuel gas is stored, and first and second gas supply pipes 28 that individually guide the fuel gas from the gas supply source 25 to the internal gas and external gas supply pipes 26 and 18. , 30 and flow control valves 29a, 29b for controlling the flow rate of the gas supplied from the gas supply source 25. As the fuel gas, for example, city gas can be suitably used.
[0022]
An inner cylinder 10 is mounted on the outside of the nozzle body 20. The inner cylinder 10 is a substantially cylindrical member made of stainless steel, and the inner space defines an inner flow path 45 (hereinafter referred to as a first flow path). An outward projecting portion 11 is formed at one end of the inner cylinder 10, and the outward projecting portion 11 allows air to flow into the inner flow path. The first flow path 45 is Make it easier to flow into. Inner protrusions 34 that protrude radially inwardly with an interval in the circumferential direction are integrally provided on the inner peripheral surface of the peripheral wall at one end of the inner cylinder 10. The inner cylinder 10 is coaxially supported by the nozzle body 20 via a plurality (eight in the present embodiment) of inner protrusions 34.
[0023]
3 is an enlarged cross-sectional view showing the main part of the burner device shown in FIG. 1, FIG. 4 is a cross-sectional view taken along the section line IV-IV in FIG. 3, and FIG. 5 is for convenience of illustration. FIG. 5 is a cross-sectional view of a state where the nozzle body is removed from FIG. 4. The nozzle body 20 includes a large-diameter portion 31 having a large outer diameter, an intermediate taper portion 33 extending in a taper shape inward in the radial direction, a small-diameter portion 35 having a small outer diameter, and a tip tapered portion 37, and these are the tip portions. It is provided in this order toward the side. The nozzle body 20 is attached with the tip portion directed downstream in the gas flow direction (hereinafter referred to as the downstream side). In relation to this, each inner protrusion 34 of the inner cylinder 10 has a support portion 34a whose tip surface extends in the axial direction, and an inclined portion 34b extending from the support portion 34a so as to incline radially inward. The large-diameter portion 31 of the nozzle body 20 is attached to the support portion 34a. In such a mounted state, the inclined portion 34b of the inner protrusion 34 is located opposite to the intermediate tapered portion 33 of the nozzle body 20, and a slight amount is between the intermediate tapered portion 33 and the inclined portion 34b of the inner protrusion 34. There is a gap 39. Further, between the inner cylinder 10 and the nozzle body 20, as shown in FIGS. 4 and 5, it is substantially annular in a region excluding the region where the support portion 34 a of the inner protrusion 34 exists over a predetermined range in the circumferential direction. Gap 38 is present. The gap 38 and the gap 39 between the intermediate taper portion 33 and the inclined portion 34b form an introduction channel. Air from the air flow path 8 flows in from the inlet portion of the introduction flow path, passes through the introduction flow path, and is guided to the first flow path 45 in the inner cylindrical body 10.
[0024]
An inner wall 36 is disposed between the small diameter portion 35 of the nozzle body 20 and one end portion of the inner cylinder 10. The inner wall 36 is composed of a plurality (eight in this embodiment) of swirling blades 32 arranged at intervals in the circumferential direction as shown in FIG. Adjacent to the downstream side of the inclined portion 34b, it is integrally provided on the inner peripheral surface of the inner cylindrical body 10. Therefore, the air flowing through the gap 38 between the nozzle body 20 and the inner cylinder 10 which is the introduction flow path becomes a swirl flow by the inner swirler 36, and the inside of the first flow path 45 in the swirl flow state is shown in FIG. And flows downstream in FIG. The inner wall 36 may be formed separately from the inner cylinder 10 and interposed between them.
[0025]
Referring to FIGS. 1 and 2 again, the outer cylinder 12 is mounted on the outer side in the radial direction of the inner cylinder 10 with a gap therebetween. The outer cylinder 12 is a substantially cylindrical member made of stainless steel, and defines an outer flow path 47 between the outer cylinder 12 and the inner cylinder 10. An outer wall 40 is integrally provided on the inner peripheral surface of one end of the outer cylindrical body 12, that is, the inlet portion of the outer flow path 47, and the outer cylindrical body 12 is disposed on the outer peripheral surface of the inner cylindrical body 10 via the outer wall 40. Is mounted coaxially. The outer wall 40 is composed of a plurality of (12 in the present embodiment) swirl blades disposed at intervals in the circumferential direction, like the inner wall 36. Since the outer swirler 40 is thus provided, the air introduced from the inlet portion of the outer flow path 47 becomes a swirling flow by the action of the outer swirler 40, and the outer flow path 47 is swung in the swirling state in FIGS. 1 and 2. Flows downstream. The outer swirler 40 may be formed separately from the outer cylinder 12 and interposed between the inner cylinder 10 and the outer cylinder 12.
[0026]
An annular flange 42 that protrudes radially outward is integrally provided at one end of the outer cylinder 12, and one end of the combustion cylinder 14 is attached to the tip of the annular flange 42 with an attachment screw. The combustion cylinder 14 is disposed coaxially with the inner cylinder 10 and the outer cylinder 12, and a substantially annular space 51 exists between the combustion cylinder 14 and the combustion cylinder 6. A substantially straight cylindrical tube portion 41 is provided at the central portion in the length direction of the outer cylindrical body 12, and a ring plate-shaped outer portion is connected to the other end portion of the outer cylindrical body 12 via a curved portion 43. A facing protrusion 44 is formed.
[0027]
In the present embodiment, as shown in FIGS. 3 and 4, a plurality (eight in this embodiment) of pilot nozzle holes 46 are formed in the tip tapered portion 37 of the nozzle body 20 at intervals in the circumferential direction. These pilot nozzle holes 46 communicate with the first space 22a of the nozzle body 20. A plurality (eight in this embodiment) of main nozzle holes 48 extending in a substantially radial direction are formed in the intermediate taper portion 33 of the nozzle body 20 at intervals in the circumferential direction. These main nozzle holes 48 are communicated with the second space 22 b of the nozzle body 20. Further, corresponding to each of the main nozzle holes 48, a gas introduction hole 50 is formed in the inclined portion 34 b of the inner protrusion 34 of the inner cylinder 10 so as to penetrate the peripheral wall of the inner cylinder 10. The introduction holes 50 are arranged opposite to each other with the gap 39 interposed therebetween.
[0028]
The axes of the main nozzle hole 48 and the gas introduction hole 50 exist in a virtual plane including the axis 10a of the inner cylinder 10 and are on a common straight line in the virtual plane. The common axis 49 extends away from the axis 10a of the inner cylinder 10 toward the downstream side, and an angle θ formed by the axis 49 and the axis 10a (hereinafter referred to as a main nozzle hole ejection angle) is 10 degrees. It is set to a value in the range of ≦ θ ≦ 90 degrees. The upper limit value of the main nozzle hole ejection angle θ is limited to 90 degrees because the main nozzle hole 48 and the gas introduction hole 50 are inclined to the intermediate tapered portion 33 and the inner protrusion 34 of the nozzle body 20 at an angle exceeding the upper limit value. This is because it is physically difficult to form the portion 34b. The reason for limiting the lower limit value of the main nozzle hole ejection angle θ will be described later. The inner diameter D1 of the gas introduction hole 50 is preferably set to be substantially equal to or larger than the inner diameter D2 of the main nozzle hole 48 of the nozzle body 20. As a result, the fuel gas ejected from the main nozzle hole 48 easily flows into the gas introduction hole 50.
[0029]
A partition cylinder 54 is provided between the inner cylinder 10 and the outer cylinder 12. The partition cylinder 54 is a substantially cylindrical member made of stainless steel, and partitions the outer flow path 47 in the radial direction. The cross-sectional area of the inner flow path 55 (hereinafter referred to as the second flow path) partitioned by the partition cylinder 54 is smaller than the cross-sectional area of the outer flow path 56 (hereinafter referred to as the third flow path). Formed as follows. The reason for this will be described later. One end of the partitioning cylinder 54 on the upstream side in the gas flow direction is attached to the downstream side of the axis 49 as shown in FIG. The magnitude of the shift is represented by a distance L2 from the intersection K to one end of the partition cylinder, where K is the intersection of the axis 49 and the extension of the partition cylinder 54. In the present embodiment, it is preferable that the ratio R (= L2 / L1 × 100) to the total length L1 of the partition cylinder 54 having the displacement L2 is set to a value in the range of 0 ≦ R ≦ 80%. The reason for this will also be described later.
[0030]
With this configuration, the fuel gas supplied via the gas supply pipe 28 is supplied to the first space 22a of the nozzle body 20 via the internal gas supply pipe 26, and the pilot nozzle hole 46 is supplied. Is ejected through. The inner cylinder 10 defines a first flow path 45 as shown in FIGS. 1 and 2, and one end portion, that is, the upstream side portion of the first flow path 45 is between the nozzle body 20 and the inner cylinder body 10. And the introduction channel is formed. Part of the air flowing through the air flow path 8 passes through the introduction flow path and flows into the first flow path 45 on the downstream side. The fuel gas ejected from the pilot nozzle hole 46 is ejected toward the air flow forming the swirling flow by the inner wall 36 and is substantially uniformly mixed by the action of the swirling flow to become a lean mixed gas. The amount of fuel gas ejected from the pilot nozzle hole 46 can be controlled by operating the flow control valve 29a of the gas supply device 27.
[0031]
The fuel gas supplied through the gas supply pipe 30 is supplied to the nozzle body 20 through the outer gas supply pipe 18. 2 It is supplied to the space 22 b and is ejected from the main nozzle hole 48. As shown in FIGS. 1 to 3, the outer cylindrical body 12 and the partitioning cylindrical body 54 define substantially annular second and third flow paths 55 and 56, and a part of the air flowing through the air flow path 8 is an outer wall. It flows into the 2nd and 3rd flow paths 55 and 56 via 40, and flows downstream. As will be described later, the fuel gas ejected from the main nozzle hole 48 passes through the gap 39 to the first flow path 45 and crosses the gap 39 to the outer flow path 47 through the gas introduction hole 50. . The fuel gas ejected into the outer flow path 47 is ejected toward the air flow forming the swirl flow by the outer swirler 40, and is uniformly mixed by the action of the swirl flow to become a lean mixed gas. The amount of fuel gas ejected from the main nozzle hole 48 can be controlled by operating the flow control valve 29b of the gas supply device 27.
[0032]
The remaining air flowing through the air flow path 8 flows through the space 51 between the combustion cylinder 14 and the combustion case 6. In the present embodiment, a plurality of air holes 52 are formed in the combustion cylinder 14 at intervals in the circumferential direction and the axial direction, and the air flowing through the space 51 passes through these air holes 52 and burns. It is introduced into the cylinder 14. The air introduced through the air holes 52 forms an air layer that flows along the inner peripheral surface of the combustion cylinder 14, and the combustion cylinder 14 is cooled by this air layer. The combustion cylinder 14 is provided with a dilution hole 53 so that air flowing through the space 51 passes through the dilution hole 53 and is introduced into the combustion cylinder 14 so that the temperature of the combustion gas does not rise abnormally due to the introduced air. Is lowered.
[0033]
The other end portions of the inner cylinder body 10, the partition cylinder body 54, and the outer cylinder body 12 (hereinafter sometimes referred to as the front end portions) are downstream to substantially the same position or substantially the same position as shown in FIGS. The other end of the combustion cylinder 14 extends further downstream than these. Therefore, the combustion flame by the mixed gas flowing through the first flow path 45 is generated downstream from the inside or the front end portion of the inner cylinder 10, and the combustion flame by the mixed gas flowing through the second and third flow paths 55 and 56 is The partition cylinder 54 and the outer cylinder 12 are generated downstream from the distal ends.
[0034]
In the present embodiment, the gas concentration of the mixed gas flowing through the first flow path 45 is set to be higher than the gas concentration of the mixed gas flowing through the second and third flow paths 55 and 56. In connection with this, a spark plug 58 for igniting the mixed gas is provided so as to protrude into the first flow path 45. The spark plug 58 has a base portion attached to the holding case 4, and a tip portion that penetrates the combustion case 6, the combustion cylinder 14, the outer cylinder body 12, the partition cylinder body 54, and the inner cylinder body 10, and the first flow path 45. Protrusively inside. The front ignition part of the spark plug 58 generates a spark toward the mixed gas flowing through the first flow path 45, and the mixed gas in the first flow path 45 is ignited and burned by this spark. Further, the flame of the combustion gas generated in the first flow path 45 is propagated to the mixed gas flowing in the second and third flow paths 55 and 56, and the mixed gas of the second and third flow paths 55 and 56 is propagated by this flame propagation. Is burned.
[0035]
The gap between the nozzle body 20 and the inner cylinder 10 that defines the introduction flow path is set to be smaller than the gap between the inner cylinder 10 and the partition cylinder 54 and the gap between the partition cylinder 54 and the outer cylinder 12. ing. As a result, the cross-sectional area of the inlet portion of the introduction flow path is smaller than the cross-sectional area of the inlet portion of the outer flow path 47, so that the air flow rate flowing into the first flow path 45 that is the inner flow path via the introduction flow path is The flow rate is smaller than the flow rate of air flowing into the outer flow path 47. In addition, the air flowing in from the inlet portion of the introduction flow path passes through the narrow gap of the introduction flow path and then flows into the first flow path 45 having a relatively wide cross-sectional area on the downstream side. The flow rate of the air flow through 45 is relatively slow. On the other hand, the flow velocity of the airflow flowing through the second and third flow paths 55 and 56 forming the outer flow path 47 is relatively high. That is, in the present embodiment, the air flow rate in the outer flow path 47 is configured to be higher than the air flow rate in the first flow path 45. Thus, since the flow velocity and flow rate of air in the first flow path 45 are lower than those in the outer flow path 47 and smaller, even when the flow rate of the fuel gas flowing into the first flow path 45 is small, It is prevented that the equivalent ratio of the mixed gas of fuel gas and air is less than the combustible range. Therefore, the extinguishing of the combustion flame in the 1st flow path 45 is prevented, and a mixed gas can be burned stably.
[0036]
A cylindrical lead-out cylinder 60 is further provided at the tip of the combustion cylinder 14. The lead-out cylinder 60 extends to the downstream side, and its tip is tapered. The leading end of the lead-out cylinder 60 is supported by a support plate 64 attached to the leading end of the combustion case 6. The combustion gas guided from the combustion cylinder 14 to one end of the lead-out cylinder 60 passes through the lead-out cylinder 60 and is collected at the tapered tip and flows downstream. A gas turbine 62 is disposed on the leading end side of the lead-out cylinder 60, and the combustion gas burned in the combustion cylinder 14 passes through the lead-out cylinder 60 and is supplied to the gas turbine 62. As shown in FIG. 7, a plurality of such burner apparatuses 1, for example, six, are disposed with a gap in the circumferential direction of the virtual circle 63 with respect to the blades of the gas turbine 62. The gas turbine 62 is rotationally driven by the combustion gas from each burner device 1.
[0037]
In such a burner device 1, the fuel gas from the ignition gas supply device 27 is supplied to the first space 22 a of the nozzle body 20 through the inner gas supply pipe 28, and from the first space 22 a to the pilot nozzle hole 46. Fuel gas is ejected through Therefore, the fuel gas is jetted toward the air flow flowing through the first flow path 45, and a mixed gas having a relatively high concentration flows through the first flow path 45. When a spark is generated from the spark plug 58 toward the mixed gas flow, the mixed gas is combusted by the spark, and the mixed gas flowing through the first flow path 45 is combusted to become a combustion gas.
[0038]
After ignition, the fuel gas from the gas supply device 27 is supplied to the second space 22b of the nozzle body 20 through the outer gas supply pipe 18, and the fuel gas is ejected from the second space 22b through the main nozzle hole 48. Is done. The amount of fuel gas ejected is, for example, that the fuel gas crosses the gap 39 between the intermediate taper portion 33 of the nozzle body 20 and the inclined portion 34b of the inner protrusion 34 of the inner cylinder 10, passes through the gas introduction hole 50, and passes through the second flow path. It is set so that it can flow into 55. As a result, the fuel gas is ejected toward the air flow flowing through the second flow path 55, and a mixed gas having a concentration lower than the gas concentration of the mixed gas flowing through the first flow path 45 flows through the second flow path 55. . The mixed gas flowing through the second flow path 55 is combusted and becomes combustion gas when the flame from the first flow path 45 propagates to the second flow path 55.
[0039]
Thus, when the mixed gas flowing through the second flow path 55 starts to burn, the supply of the fuel gas supplied from the gas supply device 27 to the pilot nozzle hole 46 via the inner gas supply pipe 26 is stopped. In such a combustion state, if the amount of fuel gas supplied from the gas supply device 27 is reduced in order to reduce the combustion output of the burner device 1, the amount of fuel gas injected from the main nozzle hole 48 of the nozzle body 20 is reduced. The eruption speed is also reduced. When the ejection speed decreases, as is clear from FIG. 3, the fuel gas ejected from the main nozzle hole 48 passes between the large-diameter portion 31 of the nozzle body 20 and the inner cylindrical body 10 and the inner tapered portion 33 and the inner tapered portion 33. The air flow that flows through the gap 39 between the protrusion 34 and the inclined portion 34b is greatly affected, and flows toward the first flow path 45 together with the air flow. As a result, most of the fuel gas ejected from the main nozzle hole 48 flows through the first flow path 45 and the amount ejected to the second flow path 55 through the gas introduction hole 50 is reduced. Accordingly, the gas concentration of the mixed gas generated in the first flow path 45 having a relatively slow air flow and a low air flow rate becomes high, and the first flow path 45 has a small supply amount of fuel gas. The mixed gas burns stably.
[0040]
On the other hand, when the amount of fuel gas supplied from the gas supply device 27 is increased in order to increase the combustion output of the burner device 1, the amount of fuel gas injected from the main nozzle hole 48 of the nozzle body 20 increases. As a result, the ejection speed is also increased. As the fuel gas ejection speed increases, the fuel gas ejected from the main nozzle hole 48 flows through the gap 39 between the intermediate taper portion 33 of the nozzle body 20 and the inclined portion 34b of the inner protrusion 34 as is apparent from FIG. Overcoming the action of the flow, the gas flows across the gap 39 into the gas introduction hole 50 of the inclined portion 34b of the inner cylinder 10. The supply amount supplied through the gas introduction hole 50 increases as the supply amount of the fuel gas increases.
[0041]
In the present embodiment, the fuel gas flowing into the outer flow path 47 through the gas introduction hole 50 is configured so that the main inflow flow path is switched depending on the inflow amount. That is, when the inflow amount of the fuel gas is small and the inflow rate is low, the fuel gas mainly flows into the second flow path 55 by the action of the air flow from the outer wall 40, and when the inflow amount of the fuel gas is large and the inflow rate is high. The fuel gas overcomes the air flow from the outuswara 40 and mainly flows into the third flow path 56. As a result, the fuel gas mainly flows into the third flow path 56 having a large cross-sectional area and a large air flow rate when the fuel gas inflow amount is large, and the cross-sectional area is small and the air amount is small when the fuel gas inflow amount is small. Since the fuel gas mainly flows into the second flow path 55, the equivalence ratio of the mixed gas is prevented from becoming too small, and the extinction of the combustion flame on the outlet side of each flow path is prevented. Accordingly, it is possible to maintain a stable combustion state and to prevent occurrence of incomplete combustion due to extinguishing. As described above, the reason why the cross-sectional area of the third flow path 56 is formed larger than the cross-sectional area of the second flow path 55 is due to this reason.
[0042]
In order to smoothly switch the inflow passage in the outer passage 47, it is preferable to set the main nozzle hole ejection angle θ to a value in the range of 10 degrees ≦ θ ≦ 90 degrees as described above. The reason why the lower limit value of the main nozzle hole ejection angle θ is limited to 10 degrees is that when the angle is less than the lower limit value, the fuel gas flowing into the outer flow path 47 flows downstream along the outer peripheral surface of the inner cylinder 10. This is because most of the liquid flows into the second flow path 55 and does not easily flow into the third flow path 56 even if the inflow flow rate increases. Therefore, it becomes impossible to smoothly switch the main inflow channel according to the flow rate of the fuel gas. The main nozzle hole ejection angle θ is more preferably 30 degrees ≦ θ ≦ 60 degrees, and most preferably θ = 45 degrees.
[0043]
Further, in order to smoothly switch the inflow channel, as described above, the ratio R (= L2 / L1 × 100) with respect to the total length L1 of the partition cylinder 54 of the displacement size L2 with respect to the partition cylinder 54 is set. It is preferable to set a value in the range of 0 ≦ R ≦ 80%. The reason why the lower limit value of the ratio R is limited to zero is that, in the ratio R less than the lower limit value, one end portion of the partitioning cylinder 54 is upstream of the intersection K, in other words, upstream of the axis 49 of the main nozzle hole 48. This is because the fuel gas ejected from the main nozzle hole 48 along the axis 49 is less likely to flow into the third flow path 56. The reason why the upper limit value of the ratio R is limited to 80% is that when the ratio cylinder R exceeds the upper limit value, the position of the partitioning cylinder 54 is separated to the downstream side, so that the fuel gas flowing into the outer flow path 47 is uniformly mixed with air. This is because the second and third flow paths are supplied and the partition effect of the partition cylindrical body 54 cannot be exhibited. The ratio R is particularly preferably in the range of 5% ≦ R ≦ 50%.
[0044]
As described above, in the present embodiment, when the supply amount of the fuel gas is increased to increase the combustion output, the fuel gas flows into the second and third flow paths 55 and 56 of the outer flow path 47, and the fuel gas The fuel gas flows into the first flow path 45 when the supply amount of the fuel is reduced to reduce the combustion output. The air flow rate supplied to the outer flow path 47 is configured to be larger than the air flow rate supplied to the first flow path 45 that is the inner flow path. Therefore, the fuel gas corresponding to the air flow rate is supplied in each flow path, and the mixed gas can be stably burned without causing problems such as extinction of the combustion flame.
[0045]
As described above, in order to allow the fuel gas ejected from the main nozzle hole 48 of the nozzle body 20 to flow into the first flow path 45 and the outer flow path 47 in accordance with the ejection amount, the fuel gas flows through the first flow path 45. It is necessary to appropriately set the air flow velocity, the size of the main nozzle hole 48, and the gap 39 between the intermediate tapered portion 33 of the nozzle body 20 and the inclined portion 34b of the inner cylindrical body 10. These are set based on the combustion output required for the burner device 1, and for example, the gap 39 can be set to about 0.1 to 1.0 mm. In addition, in order to overcome the airflow flowing through the gap 39 and sufficiently eject the fuel gas ejected from the main nozzle hole 48 of the nozzle body 20 into the outer flow path 47, the maximum ejection speed of the fuel gas from the main nozzle hole 48 Is preferably in the range of 1 to 1000 m / s.
[0046]
As described above, in the burner device 1 of the present embodiment, as shown in Table 1, when the supply amount of the fuel gas is small, the fuel gas becomes a relatively rich mixed gas and is burned mainly in the first flow path 45, and the fuel. When the supply amount of gas is medium, it becomes a relatively thin mixed gas and burns mainly on the outlet side of the second flow path 55, and when the supply amount of fuel gas is large, it becomes a relatively thin mixed gas and mainly the second mixture gas. Combustion is performed on the outlet side of the three flow paths 56. As a result, even if the amount of fuel gas supplied from the gas supply device 27 changes greatly, the fuel gas can be stably burned. The circles in Table 1 represent flow paths through which fuel gas is mainly supplied.
[0047]
[Table 1]

[0048]
In the present embodiment, the supply of the fuel gas to the pilot nozzle hole 46 is stopped after the ignition. However, the present invention is not limited to this, and the fuel gas is always supplied to the pilot nozzle hole 46 and combusted after the ignition. You may do it. Further, the gas introduction hole 50 for guiding the fuel gas to the outer flow path 47 is formed in the inner protrusion 34 of the inner cylinder 10, but the tubular body may be provided on the inner peripheral surface of the inner cylinder 10. . The main nozzle hole 48 and the gas introduction hole 50 have the same axis, and are configured to exist in a virtual plane including the axis 10a of the inner cylindrical body 10. You may make it incline so that it may cross | intersect with respect to a virtual plane along.
[0049]
FIG. 8 is a cross-sectional view showing a simplified configuration of a main part of a burner apparatus according to another embodiment of the present invention. The structure of the burner apparatus 65 of this Embodiment is similar to the structure of the burner apparatus 1 shown in FIGS. 1-3, and attaches | subjects the same referential mark to the corresponding part, and abbreviate | omits description. It should be noted that the outer diameter of the upstream one end portion of the partitioning cylinder 66 is narrowed and formed so as to be smaller than the outer diameters of the other portions. As a result, the flow rate of air flowing into the second flow path 55 decreases, so that when the flow rate of the fuel gas flowing into the outer flow path 47 through the gas introduction hole 50 is small, the second flow path 55 that becomes the main flow path of the fuel gas. It is possible to mix less fuel gas and correspondingly reduced air. Therefore, it is possible to prevent the equivalent ratio of the mixed gas from becoming smaller than the combustible range and to prevent the combustion flame from being extinguished. As a result, the mixed gas can be combusted stably, and the fuel gas can be combusted completely.
[0050]
FIG. 9 is a cross-sectional view showing a simplified configuration of a main part of a burner apparatus according to still another embodiment of the present invention. The configuration of the burner device 68 of the present embodiment is similar to the configuration of the burner device 1, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in this embodiment, three partition cylinders are provided. The first to third partition cylinders 69, 70, 71 are provided in this order from the inside between the inner cylinder 10 and the outer cylinder 12, and the second to fifth partitions the outer flow path 47 into four. The flow paths 55, 56, 73 and 74 are defined in this order from the inside. Moreover, the cross-sectional area of each flow path is formed so as to increase toward the outside, and the cross-sectional area of the fifth flow path 74 is the largest. For this reason, the air flow rate supplied increases so that it becomes an outside channel.
[0051]
One end of the third partition cylinder 71 is attached to be shifted downstream from the axis 49 of the main nozzle hole 48. The magnitude of the deviation is represented by a distance L3 from the intersection P to one end of the third partition cylinder 71, where P is the intersection of the axis 49 and the extension of the third partition cylinder 71. The ratio R1 (= L3 / L4 × 100) with respect to the total length L4 of the third partition cylinder 71 of the displacement size L3 is a value in the range of 0 ≦ R1 ≦ 80% as in the case of the burner device 1. It is preferable that the range is 5% ≦ R1 ≦ 50%. The gas flow direction installation position and the total length of the first and second partition cylinders 69 and 70 are the same as those of the third partition cylinder 71.
[0052]
The fuel gas that has flowed into the outer flow path 47 through the gas introduction hole 50 mainly flows into the second flow path 55 when the flow rate is small, and flows into the outer flow path as the flow rate increases. As a result, in the present embodiment, the main inflow passage can be switched more finely than in the burner device 1, so that fuel gas corresponding to the flow rate of air supplied to each passage can be introduced. It is further reliably prevented that the equivalent ratio of the mixed gas in the passage becomes smaller than the combustible range.
[0053]
As described above, the present invention can be suitably used as a burner device for a combustor of a gas turbine. However, the application of the present invention is not limited to a gas turbine, and can be suitably used for a wide range of applications such as a burner device for a heating furnace.
[0054]
Example
In order to confirm the effect of the burner apparatus of the present invention, a fuel gas combustion experiment was performed using the burner apparatus 1 shown in FIGS. 1 to 3 as an example. The dimensions of each member in the burner device 1 used are as shown in Table 2. The gap 39 between the inclined portion 34b of the inner protrusion 34 of the inner cylinder 10 and the intermediate taper portion 33 of the nozzle body 20 was set to 0.5 mm. The ratio R (= L2 / L1 × 100) of the deviation L2 between the one end of the partition cylinder 54 and the axis 49 of the main nozzle hole 48 to the length L1 of the partition cylinder 54 was set to 10%. On the other hand, as a comparative example, a fuel gas combustion experiment was performed using a burner device having the same configuration as the example except that the partition cylinder was omitted.
[0055]
[Table 2]

[0056]
In a combustion experiment using such a burner device, air having a temperature of 350 ° C. is supplied through the air flow path 8 at a flow rate of 700 Nm. ^Three / H. The supplied air flowed downstream via the first flow path 45, the outer flow path 47, and the flow path 51 outside the combustion cylinder 14. The air flowing through the flow path 51 outside the combustion cylinder 14 flows into the combustion cylinder 14 through the air holes 52 of the combustion cylinder 14. Using methane as fuel gas, flow rate 1Nm ^Three / H from the pilot nozzle hole of the nozzle body 20 and a flow rate of 24.7 Nm ^Three / H from the main nozzle hole of the nozzle body 20. The supplied air and methane were mixed to form a mixed gas, which was ignited by a spark plug 58 to burn the mixed gas to generate a combustion gas. Pilot nozzle hole after ignition 46 The methane ejection from the main nozzle hole 48 was stopped and the methane ejection flow rate from the main nozzle hole 48 was reduced to 25.7 Nm. ^Three / H. The equivalent ratio of the mixed gas at this time was 0.35. Thereafter, the methane supply amount was gradually decreased, in other words, the equivalence ratio was gradually decreased, and the change in the combustion state was examined. The combustion state was evaluated based on the combustion efficiency and the NOx content in the exhaust gas. The results are shown in FIGS.
[0057]
FIG. 10 is a graph showing the relationship between the equivalent ratio of the mixed gas and the combustion efficiency, and FIG. 11 is a graph showing the relationship between the equivalent ratio of the mixed gas and the NOx content in the exhaust gas. The combustion efficiency is an index that represents the degree of complete combustion of the fuel gas in the mixed gas, and is calculated by measuring the contents (%) of CO and HC that are incomplete combustion products in the exhaust gas. These components represent that incomplete combustion occurs due to extinction of the combustion flame or the like. Therefore, when CO and HC are not included in the exhaust gas, the combustion efficiency is 100%. In FIG. 10 and FIG. 11, the experimental result of the example is represented by reference numeral 75, and the experimental result of the comparative example is represented by reference numeral 76. A reference numeral 77 in FIG. 10 represents an equivalence ratio range in which fuel gas mainly flows into the first flow path 45 of the embodiment, and a reference numeral 78 indicates that fuel gas mainly flows into the second flow path 55 of the embodiment. The reference numeral 79 represents the equivalence ratio range in which the fuel gas mainly flows into the third flow path 56 of the embodiment. Further, reference numeral 80 in FIG. 10 represents the first flow path of the comparative example, that is, the equivalence ratio range in which the fuel gas mainly flows into the inner cylinder 10, and reference numeral 81 represents the second flow path of the comparative example, An equivalent ratio range in which fuel gas mainly flows into the outer flow path is shown.
[0058]
From FIG. 10, the combustion efficiency is 100% in both the example 75 and the comparative example 76 in the range of the equivalent ratio of 0.30 to 0.35, and the equivalent ratio is low in both the example and the comparative example below the equivalent ratio of 0.30. The lower the combustion efficiency, the lower the combustion efficiency with respect to the lowering of the equivalent ratio in Example 75 than in Comparative Example 76. Therefore, when compared at the same equivalent ratio, Example 75 is compared with Comparative Example 76. This tendency is particularly good when the combustion efficiency is good, particularly when the fuel gas is mainly flowing into the second flow path 55 of the burner device 1 of the embodiment at an equivalence ratio of 0.1 to 0.25. I understand that. In addition, it can be seen from FIG. 11 that the NOx content in the exhaust gas is substantially the same as in Example 75 and Comparative Example 76, and that the NOx content in the exhaust gas is both low. Thus, the burner device 1 of the embodiment can maintain good combustion efficiency while maintaining low NOx even if the equivalence ratio is lowered, that is, the supply amount of methane is reduced.
[0059]
【The invention's effect】
As described above, according to the first aspect of the present invention, when the amount of fuel gas ejected from the main nozzle hole is small, the fuel gas mainly flows into the inner flow path having a small air inflow amount. The equivalence ratio is prevented from becoming less than the combustible range, and the combustion flame can continue to burn stably without extinguishing. In addition, since the flow path of the fuel gas mainly switches as the flow rate of the fuel gas flowing into the outer flow path increases or decreases, the equivalence ratio of the mixed gas in each flow path is maintained appropriately. Accordingly, even when the flow rate of the fuel gas flowing into the outer flow path is small, the equivalence ratio is prevented from becoming smaller than the combustible range, so that the combustion flame in the outer flow path is prevented from being extinguished. Therefore, the mixed gas can be stably burned regardless of the supply flow rate of the fuel gas, and incomplete combustion of the fuel gas can be prevented.
[0060]
According to the second aspect of the present invention, the axes of the main nozzle hole and the gas introduction hole are on a common straight line, the inner diameter of the gas introduction hole is larger than the inner diameter of the main nozzle hole, and the main nozzle hole Since the angle formed between the axis of the inner cylinder and the axis of the inner cylinder is set appropriately, the fuel gas ejected from the main nozzle hole is reliably guided to the gas introduction hole and flows into the outer flow path when the ejection amount is large be able to.
[0061]
According to the third aspect of the present invention, the one end portion of the partitioning cylinder is attached to be shifted downstream from the axis of the main nozzle hole, and the size of the shift is set appropriately. The fuel gas that has flowed into the outer flow path can be reliably guided to a desired flow path in accordance with the amount of flow.
[0062]
Further, according to the present invention as set forth in claim 4, since the outer diameter of the one end portion of the partitioning cylinder is set smaller than the outer diameter of the other portion, the inlet side cross-sectional area in the channel inside the outer channel And the amount of air flowing into the flow channel inside the outer flow channel can be reduced. In addition, when the amount of fuel gas flowing into the outer flow path is small, the flow of fuel gas flows into the flow path inside the outer flow path, so that the amount of fuel gas flowing in and the amount of air are reduced in the flow path inside the outer flow path. Accordingly, it is prevented that the equivalent ratio of the mixed gas becomes smaller than the combustible range.
[0063]
According to the fifth aspect of the present invention, the air flow rate in the inner flow path is lower than the air flow rate in the outer flow path. The air flow rate flowing into the inner flow path is smaller than the air flow rate flowing into the outer flow path. Accordingly, even when the flow rate of the fuel gas flowing into the inner flow path is small, the equivalence ratio of the mixed gas is prevented from becoming smaller than the combustible range, and the extinction of the combustion flame in the inner flow path is prevented.
[0064]
According to the sixth aspect of the present invention, since the plurality of partition cylinders are provided coaxially at intervals in the radial direction, when the amount of fuel gas flowing into the outer flow path through the gas introduction hole is small It mainly flows into the innermost flow path, and then flows into the outer flow path as the flow rate increases. In addition, since the cross-sectional area of each flow path partitioned by the plurality of partitioning cylinders is set so as to increase outward in the radial direction, the air flow rate supplied to the outer flow path is supplied to the inner flow path. More than the air flow path. As a result, the main inflow channel can be finely switched, and fuel gas corresponding to the air flow rate supplied to each channel can be introduced. Therefore, it is reliably prevented that the equivalent ratio of the mixed gas in each flow path becomes smaller than the combustible range.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a simplified configuration of a main part of a burner apparatus according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a simplified overall structure of the burner device shown in FIG. 1;
3 is an enlarged cross-sectional view showing a main part of the burner device shown in FIG. 1. FIG.
4 is a cross-sectional view taken along section line IV-IV in FIG. 3;
FIG. 5 is a cross-sectional view showing a state where a nozzle body is removed from FIG. 4;
FIG. 6 is a perspective view showing a simplified configuration of an inner wall.
FIG. 7 is a perspective view showing an arrangement state of the burner device with respect to the gas turbine.
FIG. 8 is a cross-sectional view showing a simplified configuration of a main part of a burner device according to another embodiment of the present invention.
FIG. 9 is a cross-sectional view showing a simplified configuration of a main part of a burner device according to still another embodiment of the present invention.
FIG. 10 is a graph showing the relationship between the equivalent ratio of the mixed gas and the combustion efficiency.
FIG. 11 is a graph showing the relationship between the equivalent ratio of mixed gas and the NOx content in exhaust gas.
[Explanation of symbols]
1,65,68 Burner device
8 Air flow path
10 Inner cylinder
12 outer cylinder
14 Combustion cylinder
20 Nozzle body
27 Gas supply device
29 Flow control valve
34 Inner protrusion
36 Innaswara
40 Outuswara
45 First channel
46 Pilot nozzle hole
47 Outer channel
48 Main nozzle hole
50 Gas introduction hole
52 Air holes
54 Partition cylinder
55 Second channel
56 Third flow path
58 Spark plug
60 Lead tube

Claims (6)

A nozzle body having a main nozzle hole for ejecting fuel gas and a pilot nozzle hole;
An inner cylinder that surrounds the nozzle body and defines an inner flow path, and an introduction flow path that is connected to the inner flow path is defined between the nozzle body and the inner cylinder, An inner cylinder in which a gas introduction flow hole is formed on the peripheral wall of the cylinder so as to face the main nozzle hole and sandwich the introduction flow path;
An outer cylinder that is provided radially outwardly of the inner cylinder and that defines an outer flow path; and
Provided between the inner cylinder and the outer cylinder , one end on the upstream side in the gas flow direction is provided on the downstream side in the gas flow direction with respect to the axis of the main nozzle hole and the gas introduction hole, and the outer flow path is arranged in the radial direction. A cylindrical partition cylinder for partitioning into a plurality of flow paths ;
Gas supply means for supplying fuel gas to the nozzle body;
The burner apparatus characterized by including the air supply means which supplies air to an introduction flow path and an external flow path. The axis of the main nozzle hole and the gas introduction hole exists on a common straight line, and the inner diameter of the gas introduction hole is larger than the inner diameter of the main nozzle hole, and the axis of the main nozzle hole and the axis of the inner cylinder are formed. The burner apparatus according to claim 1, wherein the angle θ is a value in a range of 10 degrees ≤ θ ≤ 90 degrees. One end portion on the upstream side in the fuel gas flow direction of the partition cylinder is attached to be shifted downstream from the axis of the main nozzle hole, and the ratio R to the total length of the partition cylinder of the size of the shift is 0. 3. The burner device according to claim 1, wherein the burner device has a value in a range of ≦ R ≦ 80%. The burner device according to any one of claims 1 to 3, wherein an outer diameter of one end portion of the partitioning cylinder is smaller than an outer diameter of other portions. The burner device according to any one of claims 1 to 4, wherein a flow rate of air in the outer flow path is higher than a flow speed of air in the inner flow path. The plurality of partition cylinders are provided coaxially at intervals in the radial direction, and the cross-sectional area of each flow path partitioned by the plurality of partition cylinders increases toward the outer side in the radial direction. The burner device according to any one of 5.

Images