摘要
设计了一台船用柴油机稳态扫气光学试验装置,用以研究低速二冲程船用柴油机的扫气过程.利用立体粒子图像测速技术对不同参数下的缸内扫气流场进行了研究.结果表明:随着扫气口径向切角的增大,平均涡心位置与气缸轴线的偏离增大,涡流强度有所增强,气流的轴向速度呈现先增大后减小的趋势;随着扫气口开度的减小,涡心附近的轴向速度先有所增大,当扫气口开度降低到25%时,轴向速度大幅度减小,并出现回流现象.为通过流场评估扫气性能,提出了“扫气非均匀性系数”.试验发现在扫气口径向切角为15°及20°时扫气性能较好,此外,扫气口开度对扫气性能的影响仅体现在扫气口开度较小时,此时在扫气口附近的轴向速度均匀性差,影响扫气性能.
An optical steady-state model of marine engine was designed in this study to investigate the scavenging process of a low-speed two-stroke marine diesel engine.The in-cylinder flow field under different parameters was analyzed by using the stereo particle image velocimetry(PIV).The results show that with the increase of the scavenging port angles,the average vortex center deviates from the cylinder axis,the swirl strength increases,and the axial velocity first increases and then decreases.As the opening of the scavenging port becomes smaller,the axial velocity near the vortex core increases first.When the opening is reduced to 25%,the axial velocity is greatly reduced,and backflow occurs.To evaluate scavenging performance,the concept of “scavenging non-uniformity coefficient” was proposed.It was found that the scavenging performance is good when the radial cutting angle of the scavenging port is 15° and 20°.In addition,the effect of the opening of the scavenging port on the scavenging performance is important only when the opening is small.At small opening,the axial velocity near the scavenging part is less uniform, deteriorating the scavenging performance.
作者
张备
王天友
崔磊
鲁祯
孙凯
田福全
Zhang Bei;Wang Tianyou;Cui Lei;Lu Zhen;Sun Kai;Tian Fuquan(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;Hudong Heavy Machinery Company Limited,Shanghai 200129,China)
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2019年第3期228-235,共8页
Transactions of Csice
基金
国家自然科学基金资助项目(51506142)
国家杰出青年科学基金资助项目(51525603)
高科技船舶科研计划-船用低速柴油机创新工程资助项目(一期)
关键词
二冲程船用柴油机
扫气口结构
扫气非均匀性系数
two-stroke marine diesel engine
structure of scavenging port
scavenging non-uniformity coefficient
