JP2020079563A - Compression ignition type engine - Google Patents
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Abstract
Description
本発明は、圧縮着火式エンジンに関する。 The present invention relates to a compression ignition type engine.
所望トルクを得る為に必要な量の燃料を噴射（メイン噴射）する直前に、少量の燃料を噴射（パイロット噴射）する等、１燃焼サイクル中に燃料を複数回噴射（多段噴射）させる燃料噴射制御装置が開示されている。これにより、メイン噴射に起因した燃焼（メイン燃焼）による熱発生率の上昇速度を遅くさせ、メイン燃焼に伴い生じる燃焼騒音の低減を図っている。 Injecting a small amount of fuel (pilot injection) immediately before injecting the required amount of fuel (main injection) to obtain the desired torque, for example, fuel injection in which fuel is injected multiple times during one combustion cycle (multistage injection) A controller is disclosed. As a result, the rate of increase in the heat generation rate due to the combustion (main combustion) caused by the main injection is slowed down, and the combustion noise caused by the main combustion is reduced.
例えば、理想の熱発生率波形を熱発生率ピーク値ｄＱ／ｄθｍａｘが低く、熱発生期間が長い三角形の波形とし、熱発生率の波形を当該理想の波形に近づけることで燃焼騒音を低減する技術が開示されている（特許文献１）。当該理想の熱発生率波形に近づけるために、燃焼噴射を複数回に分割し、それぞれの噴射インターバルを短くした近接多段噴射を行い，多段の熱発生率ピーク波形を形成することが開示されている。 For example, the ideal heat release rate waveform is a triangular waveform having a low heat release rate peak value dQ/dθ max and a long heat release period, and combustion noise is reduced by bringing the heat release rate waveform close to the ideal wave form. A technique is disclosed (Patent Document 1). In order to approximate the ideal heat release rate waveform, it is disclosed that the combustion injection is divided into a plurality of times, and the adjacent multi-stage injection with each injection interval shortened to form a multi-stage heat release rate peak waveform. .
また、主に予混合圧縮自着火燃焼（ＰＣＣＩ燃焼）等の予混合燃焼での燃焼騒音低減を狙った技術が開示されている（特許文献２）。当該文献では、熱発生期間を調整して燃焼騒音スペクトルの２〜５ｋＨｚの周波数範囲に谷（溝）を形成して燃焼騒音を低減する技術が開示されている。このとき、周波数スペクトルにおける谷の周波数ｆ０と熱発生期間Ｔとの関係を実験結果から求めた関係式で記述している。 Further, a technique mainly aimed at reducing combustion noise in premixed combustion such as premixed compression self-ignition combustion (PCCI combustion) is disclosed (Patent Document 2). This document discloses a technique of adjusting the heat generation period to form valleys (grooves) in the frequency range of 2 to 5 kHz of the combustion noise spectrum to reduce combustion noise. At this time, the relationship between the frequency f 0 of the valley in the frequency spectrum and the heat generation period T is described by the relational expression obtained from the experimental result.
圧縮着火式内燃機関の燃焼騒音を低減するためには，燃焼室内圧力の時間微分値（クランク角微分値）ｄＰ／ｄθの最大値（ｄＰ／ｄθｍａｘ）を下げることが広く知られている。 In order to reduce the combustion noise of the compression ignition type internal combustion engine, it is widely known to lower the maximum value (dP/dθ max ) of the time differential value (crank angle differential value) dP/dθ of the pressure in the combustion chamber.
圧縮着火式内燃機関の熱発生率波形は、着火前に噴射された燃料が予混合燃焼を行う段階と、その後に噴射された燃料が空気と混合しながら燃焼する拡散燃焼の段階に分けられる。予混合燃焼割合が大きいとｄＰ／ｄθｍａｘが高くなる。そこでパイロット噴射を行い、パイロット噴射による燃料をメイン噴射前に自着火させてメイン噴射の着火遅れ期間を短くしてｄＰ／ｄθｍａｘを下げる手法がコモンレール式噴射系の登場以降に主流となった。しかしながら、高負荷運転では窒素酸化物（ＮＯｘ）やスート等の排気エミッション低減のために高圧噴射を用いることが主流となり、その背反としてメイン噴射の拡散燃焼によるｄＰ／ｄθｍａｘが高くなるという課題が生じている。 The heat release rate waveform of the compression ignition type internal combustion engine is divided into a stage in which the fuel injected before ignition performs premixed combustion and a stage in diffusion combustion in which the injected fuel burns while mixing with air. When the premixed combustion ratio is large, dP/dθ max becomes high. Therefore, a method in which pilot injection is performed, and fuel by pilot injection is self-ignited before the main injection to shorten the ignition delay period of the main injection to reduce dP/dθ max has become mainstream since the advent of the common rail injection system. However, in high-load operation, it is mainstream to use high-pressure injection to reduce exhaust emissions of nitrogen oxides (NOx), soot, etc., and the opposite is that dP/dθ max due to diffusion combustion of the main injection increases. Has occurred.
噴射回数を多段化してパイロット噴射からメイン噴射を大きな一つのピークとして燃焼させることでｄＰ／ｄθｍａｘを低下することを狙った技術では、噴射インターバルを狭めるために高応答型のピエゾ式インジェクタが必要となる。その結果、ソレノイド型インジェクタに比べて装置の製造コストが増大する。また、分割噴射を行うために、各噴射の開始時や終了時に実際の噴射圧が低下して微粒化が悪化し、スモークが増加する傾向にある。このスモークを低下するためにアフター噴射を併用すると燃費が悪化する。 In the technology aiming to reduce dP/dθ max by burning the main injection from the pilot injection as one large peak by increasing the number of injections, a highly responsive piezo injector is required to narrow the injection interval. Becomes As a result, the manufacturing cost of the device increases as compared with the solenoid type injector. Further, since the divided injection is performed, the actual injection pressure is lowered at the start and end of each injection, the atomization is deteriorated, and the smoke tends to increase. If after-injection is also used to reduce this smoke, fuel consumption will deteriorate.
また、燃焼騒音スペクトルに谷を形成して燃焼騒音低減を狙った技術では、谷が生じる周波数は実験結果からの関係式で記述されている。しかしながら、燃焼騒音スペクトルに谷が生じる機構についての知見は示されていない。また、２ｋＨｚから５ｋＨｚの周波数帯域において谷を形成することを狙っており、圧縮着火式エンジンの高負荷運転時の燃焼で問題となる２ｋＨｚ以下の周波数帯域における成分を低減させるものではない。 Further, in the technology aiming to reduce combustion noise by forming a valley in the combustion noise spectrum, the frequency at which a valley occurs is described by a relational expression based on experimental results. However, no information has been given on the mechanism by which valleys occur in the combustion noise spectrum. Further, the aim is to form a valley in the frequency band of 2 kHz to 5 kHz, and it does not reduce the component in the frequency band of 2 kHz or less which is a problem in combustion during high load operation of the compression ignition type engine.
本発明の１つの態様は、燃料を筒内に噴射して自着火により燃焼させる圧縮着火式エンジンであって、１サイクル中にパイロット噴射による燃料が着火した後にメイン噴射による燃料の噴射を行い、メイン噴射によって噴射された燃料が燃焼するメイン燃焼における熱発生率ｄＱ／ｄθの立ち上がり波形がピークを迎えるまで略直線となるようにメイン噴射の燃料噴射率を制御し、燃焼室内圧力Ｐの時間微分値の立ち上がり開始時期からピーク時期までの周波数スペクトルにおいて２ｋＨｚ以下の周波数帯域において谷を形成することで燃焼騒音を低減させることを特徴とする圧縮着火式エンジンである。 One aspect of the present invention is a compression ignition engine that injects fuel into a cylinder and burns it by self-ignition, in which fuel is injected by main injection after ignition of fuel by pilot injection during one cycle, The fuel injection rate of the main injection is controlled so that the rising waveform of the heat release rate dQ/dθ in the main combustion in which the fuel injected by the main injection is burned reaches a peak, and the time differential of the combustion chamber pressure P is controlled. The compression ignition engine is characterized in that combustion noise is reduced by forming a valley in a frequency band of 2 kHz or less in the frequency spectrum from the rising start timing of the value to the peak timing.
ここで、メイン燃焼の熱発生開始時期ｔｓｔ、熱発生開始時期ｔｓｔと熱発生率ピーク時期との間隔ｔｕｐ、熱発生率ピーク高さｄＱ／ｄθｍａｘとしたときに、熱発生率ｄＱ／ｄθの時間変化において熱発生率ピーク時期（ｔｓｔ＋ｔｕｐ）及び熱発生率ｄＱ／ｄθが０を中心点とし、熱発生率の軸方向の径をｄＱ／ｄθｍａｘとし、時間軸方向の径を間隔ｔｕｐの０．６倍とした楕円と、熱発生開始時期ｔｓｔ及び熱発生率ｄＱ／ｄθが０を通り前記楕円と接する接線とで構成される熱発生率ｄＱ／ｄθの波形以下の熱発生率ｄＱ／ｄθの波形をもつという第１の条件を満たすことが好適である。 Here, when the heat release start time t st of the main combustion, the interval t up between the heat release start time t st and the heat release rate peak time, and the heat release rate peak height dQ/dθ max , the heat release rate dQ is obtained. In the time change of /dθ, the heat generation rate peak time (t st +t up ) and the heat generation rate dQ/dθ are centered at 0, and the axial diameter of the heat generation rate is dQ/dθ max . Waveform of the heat generation rate dQ/dθ composed of an ellipse having a diameter of 0.6 times the interval t up and a tangent line where the heat generation start time t st and the heat generation rate dQ/dθ pass 0 and contact the ellipse. It is preferable to satisfy the first condition of having the following waveform of heat generation rate dQ/dθ.
また、メイン燃焼の熱発生開始時期ｔｓｔから熱発生率ピーク時期（ｔｓｔ＋ｔｕｐ）までの燃焼室内圧力Ｐの時間微分を直線とするような熱発生率ｄＱ／ｄθの波形以上の熱発生率ｄＱ／ｄθの波形をもつという第２の条件を満たすことが好適である。 Further, heat generation above the waveform of the heat generation rate dQ/dθ such that the time derivative of the combustion chamber pressure P from the heat generation start timing t st of the main combustion to the heat generation rate peak timing (t st +t up ) becomes a straight line. It is preferable to satisfy the second condition that the waveform has the rate dQ/dθ.
また、前記第１の条件及び前記第２の条件を満たすようにパイロット噴射及びメイン噴射を制御することが好適である。 Further, it is preferable to control the pilot injection and the main injection so as to satisfy the first condition and the second condition.
本発明によれば、燃焼騒音を効果的に低減することができる圧縮着火式エンジンを提供することができる。 According to the present invention, it is possible to provide a compression ignition type engine capable of effectively reducing combustion noise.
本発明の実施の形態における圧縮着火式エンジン１００は、図１に示すように、エンジン１０及びコントローラ１０２を含んで構成される。 The compression ignition type engine 100 according to the embodiment of the present invention includes an engine 10 and a controller 102, as shown in FIG. 1.
エンジン１０は、既知のように、シリンダ１２とシリンダヘッド１４とピストン１６とを備える。シリンダ１２、シリンダヘッド１４及びピストン１６によって形成される燃焼室に対して吸気ポート１８および排気ポート２０が設けられる。吸気ポート１８は吸気弁２２によって開閉され、排気ポート２０は排気弁２４によって開閉される。燃料噴射弁２６は、シリンダヘッド１４に設けられる。燃料噴射弁２６は、燃焼室内に燃料を供給できるように配置される。燃料噴射弁２６は、コモンレール式の燃料噴射手段（図示しない）に接続されており、燃焼室内に高圧の燃料が噴射できるように構成されている。燃料噴射弁２６はピエゾ駆動型、直動駆動型などの高応答に噴射回数・量などを変更できる構成、又はノズルニードルのリフト量等を制御して噴射率を可変できる構成とすることが望ましい。 The engine 10 includes a cylinder 12, a cylinder head 14, and a piston 16 as is known. An intake port 18 and an exhaust port 20 are provided for a combustion chamber formed by the cylinder 12, the cylinder head 14 and the piston 16. The intake port 18 is opened and closed by an intake valve 22, and the exhaust port 20 is opened and closed by an exhaust valve 24. The fuel injection valve 26 is provided on the cylinder head 14. The fuel injection valve 26 is arranged so that fuel can be supplied into the combustion chamber. The fuel injection valve 26 is connected to a common rail type fuel injection means (not shown), and is configured to inject high-pressure fuel into the combustion chamber. It is desirable that the fuel injection valve 26 be of a piezo drive type, a direct drive type, or the like, in which the number of injections and amount can be changed with high response, or in which the injection rate can be varied by controlling the lift amount of the nozzle needle. .
本実施の形態では、燃料噴射弁２６からの燃料制御は、マイクロコンピュータを利用して構成されたコントローラ１０２で行われる。コントローラ１０２には、少なくともエンジン１０での燃焼状態を示す状態量（燃料噴射量、負荷（アクセル開度や過給圧）、エンジン回転数、燃焼室内圧力、酸素モル濃度等）を検出する各センサ等からの信号が入力される。コントローラ１０２は、各センサから入力された燃焼の状態量を把握し、もしくは計算により燃焼の状態量を予測または補正し、これらの状態量に応じて燃料噴射弁２６からの燃料噴射（燃料噴射タイミング、燃料噴射量、燃料噴射率、噴燃料噴射回数等）が最適になるように制御する。 In the present embodiment, the fuel control from the fuel injection valve 26 is performed by the controller 102 configured using a microcomputer. The controller 102 includes sensors for detecting at least a state quantity indicating the combustion state in the engine 10 (fuel injection amount, load (accelerator opening or boost pressure), engine speed, combustion chamber pressure, oxygen molar concentration, etc.). A signal from the etc. is input. The controller 102 grasps the combustion state quantity input from each sensor or predicts or corrects the combustion state quantity by calculation, and injects fuel from the fuel injection valve 26 (fuel injection timing according to these state quantities. , Fuel injection amount, fuel injection rate, injection fuel injection frequency, etc.) are optimized.
燃料噴射は、予混合燃焼用となるパイロット噴射と、拡散燃焼用となるメイン噴射とを組み合わせて行われる。メイン噴射は、圧縮上死点（ＴＤＣ）付近からＴＤＣ後の膨張行程に掛けて拡散燃焼が行われるようにその噴射タイミングが設定される。メイン噴射は、エンジン１０において要求トルクを発生させるために行われる。パイロット噴射は、ＴＤＣよりも前に行われる。パイロット噴射は、メイン噴射の着火遅れ期間を短縮させ、燃焼騒音を低下させるために行われる。 Fuel injection is performed by combining pilot injection for premixed combustion and main injection for diffusion combustion. The injection timing of the main injection is set so that diffusion combustion is performed from the vicinity of the compression top dead center (TDC) to the expansion stroke after TDC. The main injection is performed to generate the required torque in the engine 10. Pilot injection is performed before TDC. The pilot injection is performed to shorten the ignition delay period of the main injection and reduce combustion noise.
図２は、圧縮着火式エンジン１００のクランク角（Ｃｒａｎｋ Ａｎｇｌｅ）に対する熱発生率（ＲＯＨＲ）の変化の例を示す。また、図３は、圧縮着火式エンジン１００のクランク角（Ｃｒａｎｋ Ａｎｇｌｅ）に対する燃焼室内圧力Ｐの変化を示す燃焼室内圧力Ｐの時間微分（ｄＰ／ｄθ）を示す。ここでは、クランク角に対して立ち上がりが直線となる三角形状の熱発生率の変化となるように燃焼が生じ、その立ち上がり幅ｔｕｐ（＝２．５°、３．５°、５．０°、７．５°）を変更した例を示している。なお、圧縮着火式エンジン１００では、クランク角は時間に応じて変化するので、以下の説明においてクランク角を時間に置き換えてもよい。 FIG. 2 shows an example of changes in the heat release rate (ROHR) with respect to the crank angle (Crank Angle) of the compression ignition engine 100. Further, FIG. 3 shows a time derivative (dP/dθ) of the combustion chamber internal pressure P indicating a change in the combustion chamber internal pressure P with respect to the crank angle of the compression ignition type engine 100. Here, combustion occurs such that the heat generation rate changes in a triangular shape whose rising is linear with respect to the crank angle, and the rising width t up (=2.5°, 3.5°, 5.0°). , 7.5°) is changed. In the compression ignition engine 100, the crank angle changes with time, so the crank angle may be replaced with time in the following description.
図４〜図６は、図２に示す立ち上がり幅ｔｕｐ（＝２．５°、３．５°、５．０°、７．５°）の熱発生率の変化を生じたときの燃焼騒音の周波数スペクトルを解析した結果を示す。図４〜図６に示すように、立ち上がりが直線となる三角形状の熱発生率波形で燃焼するとき、その立ち上がり幅ｔｕｐを周期とする周波数を中心にして燃焼騒音の周波数スペクトルに谷が生じることが発明者らの研究で判明した。圧力微分（ｄＰ／ｄｑ）波形の上昇期間に最もフィットする周波数を基本波（ｘ１）とするとき，圧力微分（ｄＰ／ｄｑ）波形に最もフィットしない２倍波（ｘ２，周期＝ｔｕｐ）がスペクトルで谷の中心となる。熱発生率ピーク高さｄＱ／ｄθｍａｘを固定したまま立ち上がり幅ｔｕｐを大きくしていくと、燃焼騒音の周波数スペクトルの谷が低周波数側へ移動し、４倍波（ｘ４）、６倍波（ｘ６）を中心とした谷も現れる。これに伴って、全周波数範囲（オーバーオール）の燃焼騒音が低下する。 4 to 6 show combustion noise when the heat release rate changes with the rising width t up (=2.5°, 3.5°, 5.0°, 7.5°) shown in FIG. 2. The result of having analyzed the frequency spectrum of is shown. As shown in FIGS. 4 to 6, when burning with a triangular heat release rate waveform having a linear rise, a valley occurs in the frequency spectrum of the combustion noise centered on the frequency having the rise width t up as a cycle. It was found by the inventors' research. When the frequency that best fits the rising period of the pressure differential (dP/dq) waveform is the fundamental wave (x1), the second harmonic wave (x2, cycle=t up ) that does not best fit the pressure differential (dP/dq) waveform is The center of the valley in the spectrum. When the rise width t up is increased with the heat generation rate peak height dQ/dθ max fixed, the valley of the combustion noise frequency spectrum moves to the low frequency side, and the fourth harmonic (x4) and sixth harmonic A valley centered at (x6) also appears. Along with this, combustion noise in the entire frequency range (overall) decreases.
図７は、圧縮着火式エンジン１００のクランク角（Ｃｒａｎｋ Ａｎｇｌｅ）に対する熱発生率（ＲＯＨＲ）の変化の例を示す。ここでは、クランク角に対して立ち下がりが直線となる三角形状の熱発生率の変化となるように燃焼が生じ、その立ち下がり幅及びピーク状態の維持時間を変更した例を示している。図８は、図７に示す立ち下がり波形を有する熱発生率の変化を生じたときの燃焼騒音の周波数スペクトルを解析した結果を示す。図８に示すように、燃焼騒音の周波数スペクトルの谷が生じる周波数は熱発生率の立ち上がり側の変化によって決まり、立ち下がり側の波形を変えても変化しないことが判明した。 FIG. 7 shows an example of changes in the heat release rate (ROHR) with respect to the crank angle of the compression ignition type engine 100. Here, an example is shown in which combustion occurs such that the heat generation rate changes in a triangular shape with a straight fall with respect to the crank angle, and the fall width and the peak state maintenance time are changed. FIG. 8 shows a result of analyzing a frequency spectrum of combustion noise when a change in the heat release rate having the falling waveform shown in FIG. 7 occurs. As shown in FIG. 8, it was found that the frequency at which the valley of the frequency spectrum of combustion noise occurs is determined by the change in the heat generation rate on the rising side and does not change even if the waveform on the falling side is changed.
実際のエンジン燃焼では三角形状の熱発生率波形が生じることは無く、熱発生率波形のピークが丸くなり、立ち上がり波形も直線ではなく凹凸が生じる。立ち上がり波形が直線から変化していくと燃焼騒音スペクトルの谷が不明瞭になっていき、消滅する傾向がある。発明者らの研究によって、立ち上がりの波形を変えても燃焼騒音スペクトルに谷が生じる条件・範囲が判明した。 In actual engine combustion, a triangular heat release rate waveform does not occur, the peak of the heat release rate waveform is rounded, and the rising waveform is not linear but irregular. As the rising waveform changes from a straight line, the valley of the combustion noise spectrum becomes unclear and tends to disappear. The research conducted by the inventors has revealed the condition/range in which a valley occurs in the combustion noise spectrum even when the rising waveform is changed.
図９は、燃焼騒音の周波数スペクトルにおいて谷が生じる熱発生率立ち上がり波形の上限を示している。燃焼騒音の周波数スペクトルにおいて谷が生じる熱発生率立ち上がり波形は、横軸をクランク角θ（時間）、縦軸を熱発生率ｄＱ／ｄθとする２次元座標系において、横軸上の熱発生率ピーク時期（ｔｐ＝ｔｓｔ＋ｔｕｐ、０）を中心とし高さ方向半径をｄＱ／ｄθｍａｘとし横方向半径をｔｕｐの０．６倍とする楕円（破線）と、熱発生開始時期ｔｓｔ（熱発生率ｄＱ／ｄθ＝０）を通り当該楕円の左上部と接する接線とで構成される線に重なる若しくはその下側を通る波形である（条件１）。ここで、メイン燃焼の熱発生開始時期ｔｓｔと熱発生率ピーク時期ｔｐとの間隔ｔｕｐ、熱発生率ピーク高さｄＱ／ｄθｍａｘとする。 FIG. 9 shows the upper limit of the heat generation rate rising waveform in which a valley occurs in the frequency spectrum of combustion noise. The heat release rate rising waveform in which a valley occurs in the frequency spectrum of combustion noise has a heat release rate on the horizontal axis in a two-dimensional coordinate system in which the horizontal axis is the crank angle θ (time) and the vertical axis is the heat release rate dQ/dθ. peak time (t p = t st + t up, 0) and the ellipse to 0.6 times the transverse radius in the height direction radially centered and dQ / dθ max t up (broken line), and heat generation start timing t The waveform is a waveform that passes through st (heat generation rate dQ/dθ=0) and overlaps with or passes through the line formed by the tangent line that contacts the upper left portion of the ellipse (condition 1). Here, the interval t Stay up-, the heat generation rate peak height dQ / d [theta] max of the heat generation start timing of the main combustion t st and the heat generation rate peak timing t p.
また、図９は、燃焼騒音の周波数スペクトルにおいて谷が生じる熱発生率立ち上がり波形の下限を示している。上記条件の座標（ｔｓｔ、０）、（ｔｓｔ＋ｔｕｐ、ｄＱ／ｄθｍａｘ）を結ぶ直線を１辺とする三角形波形の熱発生率ｄＱ／ｄθから燃焼室内圧力を算出すると、燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの波形は時期ｔｓｔと熱発生率ピーク時期ｔｐ（間隔ｔｓｔ＋ｔｕｐ）との間で左上側に反った曲線となる。燃焼騒音の周波数スペクトルにおいて谷が生じる熱発生率立ち上がり波形の下限は、時期ｔｓｔの点と熱発生率ピーク時期ｔｐ（間隔ｔｓｔ＋ｔｕｐ）の点を直線で結んだ燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの波形に相当する熱発生率ｄＱ／ｄθの波形に重なる若しくはその上側を通る波形である（条件２）。 Further, FIG. 9 shows the lower limit of the rising waveform of the heat release rate at which valleys occur in the frequency spectrum of combustion noise. When the pressure in the combustion chamber is calculated from the heat release rate dQ/dθ of a triangular waveform having a straight line connecting the coordinates (t st , 0) and (t st +t up , dQ/dθ max ) under the above conditions as one side, The waveform of the time derivative dP/dθ of P is a curved curve to the upper left between the time t st and the heat generation rate peak time t p (interval t st+ t up ). The lower limit of the heat release rate rising waveform that causes a valley in the frequency spectrum of the combustion noise is the combustion chamber pressure P which is a straight line connecting the point of time t st and the point of heat release rate peak time t p (interval t st+ t up ). This is a waveform that overlaps with or passes above the waveform of the heat release rate dQ/dθ corresponding to the waveform of the time differential dP/dθ (condition 2).
図１０、図１１及び図１２は、上記条件１の定義で用いた楕円とその接線で熱発生率ｄＱ／ｄθの立ち上がり波形を表現し、楕円の横軸方向の長さをパラメータにした場合の熱発生率ｄＱ／ｄθの波形、燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの波形、燃焼騒音スペクトルをそれぞれ示す。エンジン回転数は１６００ｒｐｍ、熱発生上昇期間ｔｕｐはクランク角θ＝７．５°、燃焼騒音スペクトルの谷を１．３３ｋＨｚ付近に形成させるようにした。横方向半径をａ×ｔｕｐで定義し、係数ａを０から１の間で変化させた。また、燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの波形の最大値が固定となるように燃焼噴射量を調整した。 FIGS. 10, 11 and 12 show the rising waveform of the heat generation rate dQ/dθ expressed by the ellipse and its tangent line used in the definition of Condition 1 above, where the length of the ellipse in the horizontal axis direction is used as a parameter. The waveform of the heat release rate dQ/dθ, the waveform of the time differential dP/dθ of the pressure P in the combustion chamber, and the combustion noise spectrum are shown. The engine speed was 1600 rpm, the heat generation rising period t up was crank angle θ=7.5°, and the valley of the combustion noise spectrum was formed around 1.33 kHz. The lateral radius was defined as a×t up and the coefficient a was varied between 0 and 1. Further, the combustion injection amount was adjusted so that the maximum value of the waveform of the time differential dP/dθ of the combustion chamber pressure P was fixed.
係数ａが大きくなると、燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの波形のピーク付近の波形が尖った形状から丸くなっていき、ピーク位置がやや進角側へ移動する。燃焼騒音スペクトルの谷が最も深くなる周波数は熱発生率ｄＱ／ｄθの上昇期間ｔｕｐではなく燃焼室内圧力Ｐの時間微分ｄＰ／ｄθの上昇期間で決まるため、係数ａが大きくなると谷の周波数が高周波側へシフトし、谷が浅く広くなる。係数ａが０．６までは明確な谷を形成したが、係数ａが０．７になると谷が消滅した。 When the coefficient a becomes large, the waveform near the peak of the time derivative dP/dθ of the combustion chamber pressure P becomes sharp from a sharp shape to a round shape, and the peak position moves slightly to the advance side. The frequency at which the valley of the combustion noise spectrum becomes the deepest is determined not by the rising period t up of the heat release rate dQ/dθ but by the rising period of the time derivative dP/dθ of the combustion chamber pressure P. It shifts to the high frequency side, and the valley becomes shallow and wide. A clear valley was formed until the coefficient a was 0.6, but the valley disappeared when the coefficient a was 0.7.
図１３及び図１４は、積算する周波数範囲を限定せず、全周波数範囲において積算したオーバーオール燃焼騒音値と、積算する周波数範囲を１〜５ｋＨｚに限定した部分的積算燃焼騒音値を示す。燃焼騒音の周波数スペクトルにおいて谷が消える係数ａ＝０．７から徐々に係数ａを小さくしていくと、オーバーオール燃焼騒音値は約０．５ｄＢＡ低減した。低減幅が小さい理由は、燃焼騒音の周波数スペクトルにおいて１ｋＨｚ以下では値が高く、当該１ｋＨｚ以下の周波数範囲も含めて積算しているためである。熱発生率ｄＱ／ｄθの波形を変化させたときに燃焼騒音の周波数スペクトルにおける値が大きく変化するのは１ｋＨｚ以上の周波数範囲である。したがって、オーバーオール燃焼騒音値は、１ｋＨｚ以下の周波数範囲によって熱発生率ｄＱ／ｄθの波形の変化に伴う燃焼騒音の低減に対して感度が鈍る傾向がある。そこで、オーバーオール燃焼騒音値に代わって周波数範囲を限定して燃焼騒音値を算出する手法が近年用いられている。周波数範囲を１〜５ｋＨｚに限定して燃焼騒音値を積算すると、燃焼騒音スペクトル上の谷が積算範囲の左端に位置するため、谷の有無によって積算した燃焼騒音値が大きく変化し、谷が生じない係数ａ＝０．７からａ＝０．５まで下げると約１．６ｄＢＡ低下した。このように、燃焼騒音スペクトルの積算範囲左端付近に谷を形成することで周波数範囲の部分的積算燃焼騒音値を低下させることができる。 13 and 14 show an overall combustion noise value integrated in the entire frequency range without limiting the integrated frequency range, and a partial integrated combustion noise value in which the integrated frequency range is limited to 1 to 5 kHz. When the coefficient a was gradually reduced from the coefficient a=0.7 at which the valley disappeared in the frequency spectrum of the combustion noise, the overall combustion noise value was reduced by about 0.5 dBA. The reason why the reduction width is small is that the value is high below 1 kHz in the frequency spectrum of the combustion noise, and is integrated including the frequency range below 1 kHz. When the waveform of the heat release rate dQ/dθ is changed, the value in the frequency spectrum of the combustion noise changes greatly in the frequency range of 1 kHz or higher. Therefore, the overall combustion noise value tends to be less sensitive to the reduction of combustion noise due to the change of the waveform of the heat release rate dQ/dθ in the frequency range of 1 kHz or less. Therefore, in recent years, a method of calculating the combustion noise value by limiting the frequency range instead of the overall combustion noise value has been used. When the combustion noise value is integrated by limiting the frequency range to 1 to 5 kHz, the valley on the combustion noise spectrum is located at the left end of the integration range, so the integrated combustion noise value greatly changes depending on the presence or absence of a valley, and a valley occurs. When the coefficient a=0.7 to a=0.5 is decreased, the value is decreased by about 1.6 dBA. Thus, by forming a valley near the left end of the integrated range of the combustion noise spectrum, the partially integrated combustion noise value in the frequency range can be reduced.
次に、実際に４気筒エンジンを用いた試験で得た結果を示す。図１５は、試験に用いたエンジン諸元と試験条件を示す。また、図１６は、クランク角θに対する燃料の噴射パターンを示す。上死点（ＴＤＣ）から−３５°付近において５ｍｍ３／ｓｔ及び−７．８°付近において１．８ｍｍ３／ｓｔの２回のパイロット噴射を行い、その後、０．９°付近でメイン噴射を行うことで合計６６ｍｍ３／ｓｔの燃料噴射とした。 Next, the results obtained in the test using the 4-cylinder engine are shown. FIG. 15 shows engine specifications and test conditions used in the test. Further, FIG. 16 shows a fuel injection pattern with respect to the crank angle θ. Two pilot injections of 5 mm 3 /st in the vicinity of -35° and 1.8 mm 3 /st in the vicinity of -7.8° from top dead center (TDC) were performed, and then the main injection was performed in the vicinity of 0.9°. By doing so, a total of 66 mm 3 /st of fuel was injected.
図１７は、熱発生率ｄＱ／ｄθの波形を示す。この熱発生率ｄＱ／ｄθの波形は、エンジン筒内の圧力波形を３ｋＨｚのローパスフィルタを通して高周波成分を除去してから算出した波形である。２回のパイロット噴射で合計６．８ｍｍ３／ｓｔの燃料噴射が行われており、このパイロット燃料の燃焼によって明瞭な熱発生率ｄＱ／ｄθのピークが上死点（ＴＤＣ）前のクランク角θ＝５°において形成された。このパイロット燃焼によって温度が十分上昇し、メイン燃焼の着火遅れは極めて短く、メイン噴射の開始直後から直線状に熱発生率ｄＱ／ｄθが立ち上がった。この運転条件での熱発生率ｄＱ／ｄθの立ち上がり波形は、図９で示した条件１と条件２を満たす波形となった。 FIG. 17 shows a waveform of the heat release rate dQ/dθ. The waveform of the heat release rate dQ/dθ is a waveform calculated after removing the high frequency component from the pressure waveform inside the engine cylinder through a low-pass filter of 3 kHz. A total of 6.8 mm 3 /st of fuel is injected by the two pilot injections, and the combustion of this pilot fuel causes a clear peak of the heat release rate dQ/dθ to reach the crank angle θ before the top dead center (TDC). Formed at =5°. The temperature was sufficiently raised by this pilot combustion, the ignition delay of the main combustion was extremely short, and the heat release rate dQ/dθ rose linearly immediately after the start of the main injection. The rising waveform of the heat release rate dQ/dθ under these operating conditions is a waveform that satisfies the conditions 1 and 2 shown in FIG. 9.
図１８の実線は、当該運転条件における燃焼騒音の周波数スペクトルを示す。熱発生率ｄＱ／ｄθの立ち上がり期間は７°である。これは、エンジン回転数が１６００ｒｐｍであるので０．７３ｍｓに相当する。この期間から算出される谷の周波数は１．３７ｋＨｚとなる。しかしながら、パイロット噴射とメイン噴射の２つの熱発生率ｄＱ／ｄθのピークを持つ燃焼室内圧力波形から算出される燃焼騒音の周波数スペクトル（実線）には、１．３７ｋＨｚに谷が生じず、やや低周波数側に谷がシフトした。この理由は２つの熱発生率ピーク間によって生じる相殺と増幅が重なり合うためである。すなわち、メイン噴射による熱発生率ｄＱ／ｄθの立ち上がり期間ｔｕｐによって生じる１．３７ｋＨｚの左側には、２つのピーク間隔Δｔが周期の１．５倍に相当する周波数成分が相殺して生じる谷があり、右側にはΔｔが周期の２倍に相当する周波数成分が増幅する山が生じる。したがって、メイン噴射に伴う燃焼による熱発生率ｄＱ／ｄθの立ち上がり期間ｔｕｐによって生じる谷を燃焼騒音の周波数スペクトルで示すには、メイン噴射の熱発生率ｄＱ／ｄθのみを抽出した０次元サイクルシミュレーションが必要となる。図１８の破線は、メイン噴射の熱発生のみから算出した燃焼騒音の周波数スペクトルを示す。メイン噴射の熱発生のみから算出した燃焼騒音の周波数スペクトルでは、熱発生率ｄＱ／ｄθの立ち上がり期間ｔｕｐにおいて生じる谷が１．３７ｋＨｚを中心にして深く明瞭に形成された。 The solid line in FIG. 18 shows the frequency spectrum of combustion noise under the operating conditions. The rising period of the heat generation rate dQ/dθ is 7°. This corresponds to 0.73 ms because the engine speed is 1600 rpm. The valley frequency calculated from this period is 1.37 kHz. However, the frequency spectrum (solid line) of the combustion noise calculated from the pressure waveform in the combustion chamber having two peaks of the heat release rate dQ/dθ of the pilot injection and the main injection does not have a valley at 1.37 kHz and is slightly low. The valley shifted to the frequency side. The reason for this is that the cancellation and amplification caused by the two heat release rate peaks overlap. That is, on the left side of 1.37 kHz generated by the rising period t up of the heat generation rate dQ/dθ due to the main injection, there is a valley generated by offsetting the frequency component whose two peak intervals Δt are 1.5 times the cycle. There is a peak on the right side where the frequency component whose Δt is twice the cycle is amplified. Therefore, in order to show the valley generated by the rising period t up of the heat generation rate dQ/dθ due to combustion associated with the main injection by the frequency spectrum of combustion noise, a 0-dimensional cycle simulation in which only the heat generation rate dQ/dθ of the main injection is extracted. Is required. The broken line in FIG. 18 shows the frequency spectrum of the combustion noise calculated only from the heat generation of the main injection. In the frequency spectrum of the combustion noise calculated only from the heat generation of the main injection, the valley generated in the rising period t up of the heat generation rate dQ/dθ was formed deeply and clearly around 1.37 kHz.
次に、図１５に示したエンジン試験で、噴射量を増したエンジントルクを高くした試験で得た結果を示す。図１９に噴射条件を示す。主にメイン噴射量を増やして合計９７．７ｍｍ３／ｓｔの燃焼噴射とした。図２０は、熱発生率ｄＱ／ｄθの波形を示す。この運転条件でのメイン噴射による熱発生率ｄＱ／ｄθの立ち上がり波形は、クランク角θ＝０°から直線状に立ち上がるが、クランク角θ＝９°でのピークの前後は波形が丸くなっており、図９で示した条件１にほぼ重なる波形となった。図２１の実線は、当該運転条件における燃焼騒音の周波数スペクトルを示す。熱発生率ｄＱ／ｄθの立ち上がり期間は９°である。これは、エンジン回転数が１６００ｒｐｍであるので０．９４ｍｓに相当する。この期間から算出される谷の周波数は１．０７ｋＨｚとなる。図２１の破線は、メイン噴射の熱発生のみから算出した燃焼騒音の周波数スペクトルを示す。メイン噴射の熱発生のみから算出した燃焼騒音の周波数スペクトルでは、熱発生率ｄＱ／ｄθの立ち上がり期間ｔｕｐによって生じる谷が、期間ｔｕｐから算出される１．０７ｋＨｚを中心とした周波数には形成されず、１．４ｋＨｚ中心にして深く形成された。この０．３３ｋＨｚの谷の高周波数側へのシフトは、図１２が示すようにｄＱ／ｄθのピークが丸くなることによる高周波数側へのシフトであると考えられる。 Next, the results obtained in the engine test shown in FIG. 15 in which the injection amount is increased and the engine torque is increased are shown. FIG. 19 shows the injection conditions. Mainly the main injection amount was increased to a total of 97.7 mm3/st of combustion injection. FIG. 20 shows a waveform of the heat release rate dQ/dθ. The rising waveform of the heat generation rate dQ/dθ due to the main injection under these operating conditions rises linearly from the crank angle θ=0°, but the waveform is round before and after the peak at the crank angle θ=9°. , The waveform almost overlaps with the condition 1 shown in FIG. The solid line in FIG. 21 shows the frequency spectrum of combustion noise under the operating conditions. The rising period of the heat release rate dQ/dθ is 9°. This corresponds to 0.94 ms because the engine speed is 1600 rpm. The valley frequency calculated from this period is 1.07 kHz. The broken line in FIG. 21 shows the frequency spectrum of the combustion noise calculated only from the heat generation of the main injection. In the frequency spectrum of the combustion noise calculated only from the heat generation of the main injection, the valley generated by the rising period t up of the heat generation rate dQ/dθ is formed at the frequency centered at 1.07 kHz calculated from the period t up. Instead, it was formed deep with the center at 1.4 kHz. It is considered that the shift of the valley of 0.33 kHz to the high frequency side is a shift to the high frequency side due to the rounding of the peak of dQ/dθ as shown in FIG.
以上のように、本発明の実施の形態によれば、燃焼騒音を効果的に低減することができる圧縮着火式エンジンを提供することができる。 As described above, according to the embodiment of the present invention, it is possible to provide a compression ignition type engine that can effectively reduce combustion noise.
１０ エンジン、１２ シリンダ、１４ シリンダヘッド、１６ ピストン、１８ 吸気ポート、２０ 排気ポート、２２ 吸気弁、２４ 排気弁、２６ 燃料噴射弁、１００ 圧縮着火式エンジン、１０２ コントローラ。 10 engine, 12 cylinder, 14 cylinder head, 16 piston, 18 intake port, 20 exhaust port, 22 intake valve, 24 exhaust valve, 26 fuel injection valve, 100 compression ignition engine, 102 controller.
Claims (4)
１サイクル中にパイロット噴射による燃料が着火した後にメイン噴射による燃料の噴射を行い、メイン噴射によって噴射された燃料が燃焼するメイン燃焼における熱発生率ｄＱ／ｄθの立ち上がり波形がピークを迎えるまで略直線となるようにメイン噴射の燃料噴射率を制御し、燃焼室内圧力Ｐの時間微分値の立ち上がり開始時期からピーク時期までの周波数スペクトルにおいて２ｋＨｚ以下の周波数帯域において谷を形成することで燃焼騒音を低減させることを特徴とする圧縮着火式エンジン。 A compression ignition type engine that injects fuel into a cylinder and burns by self-ignition,
The fuel is injected by the main injection after the fuel is ignited by the pilot injection during one cycle, and the fuel injected by the main injection is burned. The heat generation rate dQ/dθ in the main combustion is almost straight until the rising waveform reaches its peak. Combustion noise is reduced by controlling the fuel injection rate of the main injection so that the time differential value of the combustion chamber pressure P rises to form a valley in the frequency band of 2 kHz or less in the frequency spectrum from the start timing to the peak timing. A compression ignition engine, which is characterized by
メイン燃焼の熱発生開始時期ｔｓｔ、熱発生開始時期ｔｓｔと熱発生率ピーク時期との間隔ｔｕｐ、熱発生率ピーク高さｄＱ／ｄθｍａｘとしたときに、熱発生率ｄＱ／ｄθの時間変化において熱発生率ピーク時期（ｔｓｔ＋ｔｕｐ）及び熱発生率ｄＱ／ｄθが０を中心点とし、熱発生率の時間微分軸方向の径をｄＱ／ｄθｍａｘとし、時間軸方向の径を間隔ｔｕｐの０．６倍とした楕円と、熱発生開始時期ｔｓｔ及び熱発生率ｄＱ／ｄθが０を通り前記楕円と接する接線とで構成される熱発生率ｄＱ／ｄθの波形以下の熱発生率ｄＱ／ｄθの波形をもつという第１の条件を満たすことを特徴とする圧縮着火式エンジン。 The compression ignition engine according to claim 1, wherein
When the heat generation start time t st of the main combustion, the interval t up between the heat generation start time t st and the heat generation rate peak time, and the heat generation rate peak height dQ/dθ max , the heat generation rate dQ/dθ When the heat generation rate peak time (t st +t up ) and the heat generation rate dQ/dθ are 0 as the center points in the time change, the diameter of the heat generation rate in the time differential axis direction is dQ/dθ max , and the time axis direction diameter is Below the waveform of the heat release rate dQ/dθ, which is composed of an ellipse in which is 0.6 times the interval t up , and a tangent line at which the heat release start time t st and the heat release rate dQ/dθ are 0 A compression ignition engine characterized by satisfying the first condition of having a waveform of the heat release rate dQ/dθ.
メイン燃焼の熱発生開始時期ｔｓｔから熱発生率ピーク時期（ｔｓｔ＋ｔｕｐ）までの燃焼室内圧力Ｐの時間微分を直線とするような熱発生率ｄＱ／ｄθの波形以上の熱発生率ｄＱ／ｄθの波形をもつという第２の条件を満たすことを特徴とする圧縮着火式エンジン。 The compression ignition engine according to claim 2,
The heat release rate dQ equal to or higher than the waveform of the heat release rate dQ/dθ such that the time derivative of the pressure P in the combustion chamber from the heat release start timing t st of the main combustion to the heat release rate peak timing (t st +t up ) becomes a straight line. A compression ignition engine characterized by satisfying the second condition of having a waveform of /dθ.
前記第１の条件及び前記第２の条件を満たすようにパイロット噴射及びメイン噴射を制御することを特徴とする圧縮着火式エンジン。 The compression ignition type engine according to claim 3,
A compression ignition type engine which controls pilot injection and main injection so as to satisfy the first condition and the second condition.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002047975A (en) * | 2000-07-28 | 2002-02-15 | Toyota Motor Corp | Fuel injection controller of internal combustion engine |
| JP2009270460A (en) * | 2008-05-02 | 2009-11-19 | Isuzu Motors Ltd | Engine combustion noise reducing method |
| JP2012132371A (en) * | 2010-12-22 | 2012-07-12 | Mazda Motor Corp | Fuel injection control device for vehicle mounted diesel engine |
| JP2015068284A (en) * | 2013-09-30 | 2015-04-13 | 株式会社豊田中央研究所 | Compression ignition type internal combustion engine |
| JP2016145564A (en) * | 2015-02-09 | 2016-08-12 | 株式会社デンソー | Fuel injection control device |
| JP2016217215A (en) * | 2015-05-18 | 2016-12-22 | マツダ株式会社 | Fuel injection controller of engine |
| JP2018003780A (en) * | 2016-07-06 | 2018-01-11 | トヨタ自動車株式会社 | Control device of internal combustion engine |
-
2018
- 2018-11-12 JP JP2018211979A patent/JP7145044B2/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002047975A (en) * | 2000-07-28 | 2002-02-15 | Toyota Motor Corp | Fuel injection controller of internal combustion engine |
| JP2009270460A (en) * | 2008-05-02 | 2009-11-19 | Isuzu Motors Ltd | Engine combustion noise reducing method |
| JP2012132371A (en) * | 2010-12-22 | 2012-07-12 | Mazda Motor Corp | Fuel injection control device for vehicle mounted diesel engine |
| JP2015068284A (en) * | 2013-09-30 | 2015-04-13 | 株式会社豊田中央研究所 | Compression ignition type internal combustion engine |
| JP2016145564A (en) * | 2015-02-09 | 2016-08-12 | 株式会社デンソー | Fuel injection control device |
| JP2016217215A (en) * | 2015-05-18 | 2016-12-22 | マツダ株式会社 | Fuel injection controller of engine |
| JP2018003780A (en) * | 2016-07-06 | 2018-01-11 | トヨタ自動車株式会社 | Control device of internal combustion engine |
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