Investigation of the Mixture Formation Process in Fuel Direct-Injection Engines for Reducing COィイD22ィエD2 Emission

燃油直喷发动机中混合气形成过程减少 CO2D22 排放的研究

基本信息

批准号：
10650209
负责人：
WAKISAKA Tomoyuki
金额：
$ 2.56万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650209/
关键词：
Fuel Direct-Injection Engine Mixture Formation Process Reduction of COィイD22ィエD2 Emission Fuel Spray Model Numerical Analysis Direct-Injection Diesel Engine Gasoline Direct-Injection Engine Premixed Compression Ignition 筒内直接燃焼噴射期関燃料噴霧モデル

项目摘要

In regard to internal combustion engines, reduction of COィイD22ィエD2 and other pollutant emissions is required for protecting the environment. Direct-injection diesel engines are advantageous in COィイD22ィエD2 emission, but both of NOィイD2xィエD2 and soot emissions have to be reduced urgently. Therefore, premixed lean combustion diesel engines which can reduce those emissions are expected to become practicable. Concerning gasoline engines, gasoline direct-injection engines which can reduce COィイD22ィエD2 emission have been made practicable. In these engines, the appropriate control of mixture formation and combustion is an important technical task.This research project aims that physical models for numerically analyzing fuel sprays are examined to improve their accuracy, and the process of mixture formation in direct-injection engines is made clear. Various models for fuel sprays have been incorporated into the investigator's GTT code, whose validity and accuracy have been confirmed. Concerning p … More remixed compression ignition engines, the behavior of a hollow-cone spray injected from a swirl nozzle or a pintle nozzle in the initial period of compression stroke with swirl in the cylinder, and furthermore the behavior of solidcone sprays injected from a pair of hole nozzles to impinge each other have been numerically analyzed. It has been found that the mixture concentration distribution in the cylinder becomes a ring shape. Therefore, it is necessary to make the mixture concentration uniform for reducing the NOィイD2xィエD2 emission much more. It has been shown that the tumble vortex or inclined swirl is effective for making the distribution of mixture concentration uniform. Concerning gasoline direct-injection engines, the injection boundary condition and the model coefficients of the droplet breakup model for the hollow-cone spray injected from a swirl injector have been examined and a spray model which can predict the actual spray shape and the droplet mean diameter has been proposed, and the effects of combustion chamber shape and gas flow on the mixture concentration distribution in the combustion chambers of actual engines have been made clear. Less

对于内燃机来说，为了保护环境，需要减少COD22D2等污染物的排放。直喷式柴油机在COD22排放方面具有优势，但NOI D2x和烟尘排放也亟待减少，因此，预混稀薄油是亟待解决的问题。可以减少这些排放的内燃柴油发动机预计将变得可行。对于汽油发动机，可以减少这些排放的汽油直喷发动机预计将变得可行。在这些发动机中，CO2D22 排放已成为现实，对混合物形成和燃烧的适当控制是一项重要的技术任务。本研究项目的目的是检查用于数值分析燃油喷雾的物理模型，以提高其准确性以及混合物形成过程。研究人员的 GTT 代码已明确了燃油喷射的各种模型，其有效性和准确性已得到证实。对气缸内有涡流的压缩冲程初始阶段从旋流喷嘴或枢轴喷嘴喷射的空心圆锥喷雾以及从一对孔喷嘴喷射的实心圆锥喷雾相互碰撞的行为进行了数值分析。研究发现，气缸内的混合物浓度分布呈环形，因此，为了进一步减少NOID2xD2排放，必须使混合物浓度均匀。对于汽油直喷发动机来说，滚转涡流或倾斜涡流对于使混合气浓度分布均匀非常有效，建立了涡流喷射器喷射的空心锥喷雾的喷射边界条件和液滴破碎模型的模型系数。并提出了可以预测实际喷雾形状和液滴平均直径的喷雾模型，明确了燃烧室形状和气流对实际发动机燃烧室中混合气浓度分布的影响。