摘要
以一台水冷式增压柴油机为研究样机,采用内窥镜式高速摄影技术和温度场测量技术,搭建了用于内燃机缸盖鼻梁区冷却水腔内汽液两相流动与传热研究的可视化试验系统.通过试验发现,在标定工况下,缸盖鼻梁区冷却水腔内存在着大量气泡,并观察到了这些气泡的形成、附着、扩散以及湮灭现象.研究结果表明:随着冷却流量的下降,气泡数量大幅下降,而气泡尺寸有所增大;同时,在热流密度较高的区域,由于存在着一定程度的沸腾换热,测点温度并没有随冷却流量的大幅下降而有显著的提高,而在热流密度不高的区域内,测点温度却有所提高.
With respect to a turbocharged diesel engine with liquid cooling system,a visualization study on the vaporliquid two-phase flow and heat transfer in the coolant jacket of bridge zone of cylinder head of internal combustion engines was studied by using the endoscopic high speed photography technology and temperature measurement technique.Experimental results show that there are large number of bubbles in the coolant jacket of bridge zone of cylinder head.The processes of bubble formation,adhesion,diffusion and annihilation were observed at the rated condition. With the decrease of cooling flux,the number of bubble is greatly decreased,while to some extent the size of bubbles is increased.Meanwhile,because of existence of certain degree of boiling heat transfer,the temperatures of measured points in several high heat flux regions don't improve markedly as the sharp drop in cooling flux.In contrast,the temperatures of measured points in low heat flux region are remarkably increased.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2015年第5期466-471,共6页
Transactions of Csice
基金
国家自然科学基金资助项目(51406070)
江苏省自然科学基金资助项目(BK20140548)
江苏省高校自然科学研究资助项目(14KJB470001)
江苏高校优势学科建设工程资助项目(PAPD)
关键词
内燃机
鼻梁区
冷却水腔
汽液两相
可视化试验
沸腾传热
internal combustion engine
bridge zone
cooling water jacket
vapor-liquid two-phase
visualization experiment
boiling transfer
