摘要
为进一步提升柴油机缸盖鼻梁区散热能力且解决多孔射流冲击下的干涉问题,提出了采用纳米流冷却液雾化冲击冷却方案,利用计算机仿真计算、高速摄影和柴油机台架综合测试研究了不同冷却方案对缸盖高热密度区换热效果和柴油机工作性能的影响。结果表明,采用雾化冲击冷却方式,因其冷却液沸腾换热以核态沸腾为主,传热效率高,故能实现缸盖高热密度区的良好冷却且温度比较均匀,温差小于6℃;该冷却方式还可增大柴油机的进气质量流量,在两种测试工况下,比传统冷却方式分别增加4%和8%。同时使NOx和烟度排放分别下降10×10-6和11%~15%。
In order to further enhance the heat dissipation capacity of cylinder head bridge zone of diesel engine and solve the problem of interference in multiple jet impingement,a scheme of atomized jet impingement cooling with nanofluid coolant is proposed,and the influences of different cooling schemes on the heat exchange effects in the high thermal density zone of cylinder head are studied by computer simulation,high speed photography and comprehensive bench tests. The results show that the atomized jet impingement cooling scheme,due to the dominance of nucleate boiling in the boiling heat transfer of nanofluid coolant with high heat transfer efficiency,can achieve better cooling of the high thermal density zone of cylinder head and more even temperature distribution with a temperature difference less than 6℃. The cooling scheme can also increase the induction mass flow rate by 4%and 8% respectively at two working conditions and reduce the NOxand soot emissions by 10 × 10-6and 11% to15% respectively,compared with traditional cooling scheme.
出处
《汽车工程》
EI
CSCD
北大核心
2017年第1期107-112,共6页
Automotive Engineering
基金
国家自然科学基金(51366006)
福建省自然科学基金(2015J01223)
福建省高校新世纪优秀人才支持计划(2015年度)
福建省中青年教师教育科研项目(JA15612)资助
关键词
柴油机
缸盖
纳米流
雾化冲击冷却
沸腾换热
试验研究
diesel engine
cylinder head
nanofluids
atomized jet impingement cooling
boiling heat exchange
experimental study
