2612 二重円筒間高クヌッセン数クエット流に発生するすべり速度の計測(S44-2 マイクロ・ナノ流れの実験・計測,S44 マイクロ・ナノフルイディクス)  [in Japanese] 2612 Measurement of slip velocity in annular Couette flow at high Knudsen numbers  [in Japanese]

The velocity slip on the solid surfaces of cylindrical Couette flow is investigated experimentally for high Knudsen numbers in vacuum pressure case. The flow was developed in two concentric cylinders. The inner cylinder is rotated at a constant speed and the torque exerted on the outer cylinder was measured a function of the varying pressure. The influence of the wall roughness was also investigated. The results show the slip begins at about Kn=3×10^<-3> and the relative slip velocity of 0.16 was obtained at Kn=0.1. It was proved that when the roughness was implemented on the outer cylinder wall, the pressure at which slip begins increased. The relative slip velocity was also changed for the same pressure comparing to the smooth surface case.