Control of Heat Loss and Pollutant Emission for Combustion in Variable-Shaped Closed Vessel

变型密闭容器燃烧热损失和污染物排放的控制

• 批准号: 07651119
• 负责人: WADA Yoshiyuki
• 金额: $ 1.41万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07651119/
• 关键词: Internal Combustion Engine; Combustion; NOx

The objective of the present study was to investigate the possibility of the control of combustion and pollutant emission characteristics using the variable-shaped combustion chamber. At the first stage of this study, the flame propagation behavior was observed for closed vessels with various shape using the schlieren photography. The variation of the chamber pressure with time was also measured. The results showed that the flame propagation behavior and pressure history were affected largely by the shape of the closed vessel. It was suggested that the shape of the flame front was one of dominant factors of the combustion characteristics. To explore the effect of the heat loss on the combustion and pollutant emission characteristics, the variation of the chamber pressure with time and NO concentration were measured with the artificial heat loss in the flame propagation. The results showed that the artificial heat loss at the early stage of the combustion leads to about 40% reduction of NO concentration, while it has little effect on the maximum chamber pressure, which is closely related to the thermal efficiency. This result indicates that the decrease in the temperature of the burned gas which due to the heat loss leads to the reduction of NO concentration. To investigate effects of gas motion and turbulence on combustion and pollutant emission characteristics, the combustion experiments of the methane jets in high temperature environments were made. The atttention was paid to the effect of the arrangement of injectors on the combustion. It was found that the NO concentration for opposed jets is lower than that for single jet. This result may be caused by the difference between mixing and combustion processes for opposed jets and single jet.

本研究的目的是探讨利用可变形状燃烧室控制燃烧和污染物排放特性的可能性。在本研究的第一阶段，使用纹影摄影观察了不同形状的密闭容器的火焰传播行为。同时测量了腔内压力随时间的变化。结果表明，密闭容器的形状对火焰的传播行为和压力历史有很大的影响。结果表明，火焰锋面形状是影响燃烧特性的主要因素之一。为了探讨热损失对燃烧和污染物排放特性的影响，利用火焰传播过程中的人工热损失测量了燃烧室压力随时间的变化和NO浓度的变化。结果表明：燃烧初期人工热损失使NO浓度降低约40%，但对最大燃烧室压力影响不大，而最大燃烧室压力与热效率密切相关。结果表明，燃烧气体温度的降低是由于热损失导致的NO浓度的降低。为了研究气体运动和湍流对燃烧和污染物排放特性的影响，进行了甲烷射流在高温环境下的燃烧实验。研究了喷油器布置对燃烧的影响。结果表明，对置喷流的NO浓度低于单喷流。这一结果可能是由于对置射流与单射流混合燃烧过程的差异造成的。