Study on the Optimization of Combustion with Relation to the Flame Behaviors in a Swirling Flow

旋流中与火焰行为相关的燃烧优化研究

• 批准号: 04650194
• 负责人: ONO Shinsuke
• 金额: $ 1.34万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650194/
• 关键词: SWIRL; CENTRIFUGAL ACCELERATION; IGNITION; LEAN COMBUSTION; LAMINARIZATION; HEAT RELEASE CONTROL; DISTURBED FLAME PROPAGATION; 火炎成層化; 消炎

As a scheme for combustion control in a swirling flow of the spark ignition engine through flame growing process, the flame behaviors which is actively controlled by the convective motion of flame and the flame initiation processes, are examined in the solid vortex model. The observed behaviors of flames initiated by 1)spark ignition at the off-centered position in a swirl, 2)using of the plasma jet igniter, 3)multi-spark ignition, illuminate how the flame growing process in the centrifugal force field depends on the flame initiation method. When a flame is initiated at the vessel center, the enhanced combustion by the swirl cannot always be realized but a decay in propagation rate appears by the lamminarization of flame front and a disturbance on the flame due to a difference in rotation speed between the unburned and the burned zone. Even if the ignition is made at the off-center position, a reduction of flame area by the wall quenching and accordingly, the increased heat loss can be avoided by the flame convection. However, too fast convection results in the earlier arrival of flame at the center, and a flame with small radius may easily be disturbed in the successive process. The flame ignited by the weak plasma jet also suffers the disturbed propagation as well as the spark ignited flame. With the increased turbulence by the powerful jet, the burning rate in the earlier stage is improved with increase of omega, but the delayd propagation soon appears in the course of the process. The single flame, whether initiated by the single spark or the plasma jet, is apt to grow the center-symmetrical flame to cause the delayd combustion. The holding of flame around ignition source results in the enhanced combustion by extending the flame area to the down stream region. When several flames can be successively initiated at a fixed ignition plug by carrying away the flame kernel with swirling flow, the rate of heat liberation may be controllable by alterling the initiation

作为一种通过火焰生长过程控制火花点火发动机旋流燃烧的方案，本文在固体涡模型中研究了火焰对流运动和火焰起燃过程对火焰行为的主动控制。通过对1）偏心位置火花点火、2）等离子体射流点火、3）多火花点火等三种点火方式所引发的火焰行为的观察，阐明了离心力场中火焰生长过程与火焰引发方式的关系。当火焰在容器中心启动时，并不总是能够实现由旋流引起的增强燃烧，而是由于未燃烧区和燃烧区之间的转速差引起的火焰前缘的层化和对火焰的扰动而出现传播速率的衰减。即使在偏离中心的位置点火，也可以通过火焰对流避免由于壁面淬火而导致的火焰面积的减小和相应的热损失的增加。但对流速度过快会使火焰提前到达中心，半径较小的火焰在后续过程中容易受到扰动。由弱等离子体射流点燃的火焰与火花点燃的火焰一样，也受到扰动传播的影响。随着强射流湍流度的增加，燃烧前期的燃速随ω的增加而提高，但在燃烧过程中很快出现延迟传播现象。单火焰无论是由单火花还是等离子体射流引发，都容易发展成中心对称火焰，导致延迟燃烧。火焰在点火源周围的稳定性通过将火焰区域延伸到下游区域而导致增强的燃烧。当用旋流带走火焰核，在固定的火花塞上连续点火时，可以通过改变点火位置来控制放热速率

项目成果

村瀬 英一,他2名: "エンジン燃焼研究用小形急速圧縮装置の開発" 内燃機関. 31巻395号. 9-13 (1992)

Eiichi Murase 等 2 人：“用于发动机燃烧研究的紧凑型快速压缩装置的开发”，《内燃机》，第 31 卷，第 395 期，第 9-13 期（1992 年）。

小野 信輔,他3名: "ハニカム触媒の安定燃焼限界について" 第31回燃焼シンポジウム(1993,11). 93-95 (1993)

Shinsuke Ono 等 3 人：“论蜂窝催化剂的稳定燃烧极限”第 31 届燃烧研讨会（1993 年，11 月）93-95（1993 年）。

村瀬 英一 他2名: "エンジン燃焼研究用小形急速圧縮装置の開発" 内燃機関. 31-395. 9-13 (1992)

Eiichi Murase 和其他 2 人：“用于发动机燃烧研究的紧凑型快速压缩装置的开发”，内燃机，31-395。

村瀬英一,他3名: "パルスジェット点火;ジェットの噴出と点火" 第30回燃焼シンポジウム 1992,12. 472-474 (1992)

Eiichi Murase 等 3 人：“脉冲射流点火；射流喷射和点火”第 30 届燃烧研讨会 1992，12. 472-474 (1992)

S.ONO, et al.: "Effects of Rotating Flow on Premixed Flame Propagation(in japanese)" Transactions of the Society of Automotive Engineers of Japan. vol.23, No.4. 53-58 (1992)

S.ONO 等人：“旋转流对预混火焰传播的影响（日语）”日本汽车工程师学会会刊。