The yttria-stabilized zirconia(YSZ)is a famous thermal barrier coating material to protect hot-end components of an engine.As a characteristic feature of the YSZ,the surface roughness shall play an important role in t...The yttria-stabilized zirconia(YSZ)is a famous thermal barrier coating material to protect hot-end components of an engine.As a characteristic feature of the YSZ,the surface roughness shall play an important role in the interface thermal conductance between the YSZ and gas,considering that the gas is typically at an extremely high temperature.We investigate the effect of the surface roughness on the thermal conductance of the YSZ-gas interface with surface roughness described by nanoscale pores on the surface of the YSZ.We reveal two competitive mechanisms related to the microstructure of the pore,i.e.,the actual contact area effect and the confinement effect.The increase of the pore depth will enlarge the actual contact area between the YSZ and gas,leading to enhancement of the solid-gas interface thermal conductance.In contrast to the positive actual contact area effect,the geometry-induced confinement effect greatly reduces the interface thermal conductance.These findings shall offer some fundamental understandings for the microscopic mechanisms of the YSZ-gas interface thermal conductance.展开更多
基金supported by the National Natural Science Foundation of China (NSFC) under Grant No. 11822206the Innovation Program of Shanghai Municipal Education Commission under Grant No. 2017-01-07-00-09-E00019
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11822206 and 12072182)the Innovation Program of the Shanghai Municipal Education Commission(Grant No.2017-01-07-00-09-E00019)+1 种基金the Key Research Project of Zhejiang Laboratorythe National Supercomputing Center in Zhengzhou(Grant No.2021PE0AC02)
文摘The yttria-stabilized zirconia(YSZ)is a famous thermal barrier coating material to protect hot-end components of an engine.As a characteristic feature of the YSZ,the surface roughness shall play an important role in the interface thermal conductance between the YSZ and gas,considering that the gas is typically at an extremely high temperature.We investigate the effect of the surface roughness on the thermal conductance of the YSZ-gas interface with surface roughness described by nanoscale pores on the surface of the YSZ.We reveal two competitive mechanisms related to the microstructure of the pore,i.e.,the actual contact area effect and the confinement effect.The increase of the pore depth will enlarge the actual contact area between the YSZ and gas,leading to enhancement of the solid-gas interface thermal conductance.In contrast to the positive actual contact area effect,the geometry-induced confinement effect greatly reduces the interface thermal conductance.These findings shall offer some fundamental understandings for the microscopic mechanisms of the YSZ-gas interface thermal conductance.