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在直喷式柴油机气缸和燃烧室中利用热线风速仪研究了紊流场的发展变化规律;在两种不同压缩间隙情况下对压缩过程中紊流场进行测量的结果表明,只有在压缩过程的初期及中期,紊流场才可以近似地当做均匀各向同性紊流场,而在循环的其它时间内,气缸和燃烧室内的紊流场属于非均匀各向异性的;通过对气缸和燃烧室中空气运动的力、能转换的分析,导出了上止点附近燃烧室内涡流转速的估算公式,利用该公式得到的结果与试验结果相当吻合。研究和探讨了燃烧室中空气涡流和紊流强度增加的原因及其影响因素。
In the direct injection diesel engine cylinder and combustion chamber, the hot-wire anemometer was used to study the development and variation of the turbulent flow field. The results of turbulent flow field measurements under two different compression gaps show that only the compression- Turbulent flow field can be approximated as homogeneous isotropic turbulent flow field in the early and middle period, while the turbulent flow fields in the cylinder and the combustion chamber belong to non-uniform anisotropy at other times of circulation. In the air movement of the force, can be converted to the analysis derived top-down near the combustion chamber eddy speed estimation formula, the results obtained using the formula and the test results quite consistent. The causes of air turbulence and the increase of turbulence intensity in the combustion chamber and their influencing factors were studied and discussed.