Elucidation of Detailed Structure of fuel sprays by Advanced optical diagnostics and the Combustion Mechanisms

通过先进光学诊断和燃烧机制阐明燃油喷雾的详细结构

• 批准号: 10305019
• 负责人: KATSUKI Masashi
• 金额: $ 25.54万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10305019/
• 关键词: Spray Combustion; Flame Luminescence; Phase Doppler Anemometer; Particle Image Velocimetry; Exciplex Fluorescence; Diesel Spray; High Temperature and Pressure Vessel; Simultaneous Multi-Component Measurement; 火災発光; Exciplex 蛍光法

Katsuki and Akamatsu : Macroscopic combustion behavior of spray flames and the optical measurementIn order to better understand the combustion behavior of spray flames, simultaneous measurements of droplet cluster visualization using laser tomography and local OH chemiluminescence and CH-band emission using a newly developed optical probe system named the Multi-color Integrated Cassegrain Receiving Optics (MICRO) are applied to a premixed-spray flame. Time-series planar images of droplet clusters and their transient structures during combustion are examined using an Ar-ion laser and a high-speed digital CCD camera. By observing the droplet clusters and local chemiluminescence simultaneously in the premixed-spray flame, it is confirmed that some portions of the spray stream disappear very rapidly due to preferential flame propagation, which is often seen in gaseous premixed flames, while other portions of the spray stream survive over a long period to form droplet clusters, disappearing … More gradually from their outermost portions, which seems similar to a diffusion-flame.Nakajima and Ikeda : Elucidation of spray structure by laser diagnostics and local chemiluminescenceThe purpose of this research was to investigate interaction between the droplet dynamics and turbulent flow in spray combustion. This research project was conducted in three phases. First of all, turbulent flow characteristics, flame holding mechanism, mixture formation and Droplet evaporation were discussed based upon the droplet velocity and size information acquired by phase Doppler anemometry (PDA), which was measured at very high data acquisition rate. Secondly, particle image velocimetry (PIV) was applied to measure instantaneous spatial structure, velocity distribution, droplet velocity of different size by size discriminating PIV, as we call 'Multi-Intensity-Layer PIV', developed. Finally, local chemiluminescence measurements of OH^*, CH^*, C2^* were performed to elucidate the relation between the fluid dynamics and chemical reactions. The transition from external to internal group combustion was observed in high temporal and spatial resolution by this technique.Fujimoto and Senda : Mixture formation process in unsteady vaporizing spraysThe object of this study is free diesel spray in unsteady and evaporative field. We analyze formation process and structure for evaporating spray in high temperature and pressure field based on the previous studies on results of non-evaporating free diesel spray. Also, we propose a structural model of evaporating diesel spray. In the experimental analysis, we mainly research the effects of injection pressure and ambient gas density on the formation process of free spray structure with exciplex fluorescence method. In the numerical analysis, the spatial distributions of droplet parcels, fuel vapor concentration, parcel velocity, and ambient gas velocity are analyzed by a modified TAB model of KIVA-II code. Finally, we propose a hybrid model which consists of a modified TAB model and DVM, for numerically analyzing both ambient gas flow and inner vortex flow of spray. Less

为了更好地了解喷雾火焰的燃烧行为，利用激光层析成像和局部OH化学发光和ch波段发射同时测量雾滴团可视化，并使用新开发的多色集成卡塞格伦接收光学（MICRO）光学探头系统对预混喷雾火焰进行了测量。利用ar离子激光器和高速数字CCD相机研究了燃烧过程中液滴团簇及其瞬态结构的时间序列平面图像。通过对预混喷雾火焰中液滴团和局部化学发光同时进行的观察，证实了在气体预混火焰中，由于火焰优先传播，喷雾流的某些部分很快消失，而其他部分则存在很长一段时间，形成液滴团，从最外层逐渐消失，类似于扩散火焰。Nakajima和Ikeda：通过激光诊断和局部化学发光来阐明喷雾结构本研究的目的是研究喷雾燃烧中液滴动力学和湍流之间的相互作用。本研究项目分三个阶段进行。首先，基于相位多普勒风速仪（PDA）以极高的数据采集速率获取的液滴速度和尺寸信息，讨论了湍流流动特性、保焰机理、混合物形成和液滴蒸发。其次，将粒子图像测速技术（PIV）应用于不同粒径的粒子图像测速技术，即“多强度层粒子图像测速技术”。最后，对OH^*、CH^*、C2^*进行了局部化学发光测量，阐明了流体力学与化学反应之间的关系。该技术在高时间和空间分辨率下观察了从外部到内部群燃烧的转变。Fujimoto and Senda：非定常汽化喷雾中混合气的形成过程本研究的对象是非定常汽化场中的自由柴油喷雾。在前人对柴油机非蒸发自由喷雾研究成果的基础上，分析了高温高压环境下蒸发喷雾的形成过程和结构。此外，我们还提出了蒸发柴油喷雾的结构模型。在实验分析中，我们主要研究了注射压力和环境气体密度对自由喷雾结构形成过程的影响。在数值分析中，采用KIVA-II代码的修正TAB模型分析了液滴包、燃料蒸气浓度、包速度和环境气体速度的空间分布。最后，我们提出了一个由改进TAB模型和DVM模型组成的混合模型，用于数值分析喷雾的环境气体流动和内部涡旋流动。少

项目成果

F.Akamatsu,M.Katsuki,Y.Ikeda,T.Nakajima: "Development of Lignt-Collecting Probe with High Spatial Resolution Applicable to Randomly Fluctuating Combustion Fields"Measurement Science and Technology. 10. 1240-1246 (1999)

F.Akamatsu，M.Katsuki，Y.Ikeda，T.Nakajima：“适用于随机波动燃烧场的高空间分辨率集光探针的开发”测量科学与技术。

河原,池田,中島: "ガンタイプバーナにおける噴霧のレーザ計測"日本機械学会論文集B編. 67. 841-848 (2001)

Kawahara、Ikeda、Nakajima：“枪式燃烧器中喷雾的激光测量”日本机械工程师学会会议录，B 版 67. 841-848 (2001)。

千田, 神田, 草野, 藤本: "液膜形成と液滴・液膜干渉を考慮した壁面衝突噴霧の分散と混合気形成過程のモデリング" 日本機械学会論文集B編. 65・629. 389-396 (1999)

Senda、Kanda、Kusano、Fujimoto：“考虑液膜形成和液滴/液膜干扰的壁撞击喷雾分散和混合物形成过程的建模”，日本机械工程师学会会刊，B 版 65・629。 (1999)

Nobuyuki Kawahara, Yuji Ikeda, Tsuyoshi Nakajima: "Interactions between Spray and Gaseous flow In Recirculating combusting Spray (in Japanese)"Transactions of JSME. 65-630B. 380-387 (1999)

Nobuyuki Kawahara、Yuji Ikeda、Tsuyoshi Nakajima：“再循环燃烧喷雾中喷雾和气体流之间的相互作用（日语）”JSME 交易。

千田,藤本: "多成分燃料の蒸発過程の解析と蒸気濃度計測"日本機械学会論文集B編. 65・640. 4106-4112 (1999)

Senda, Fujimoto：“多组分燃料的蒸发过程分析和蒸气浓度的测量”，日本机械工程师学会会刊，B 版 4106-4112（1999 年）。