努森压缩机粗糙微通道流动及增压性能研究OA北大核心CSTPCD

The models of Knudsen compressors with different rough wall microchannels were established.The effects of rough shape,rough element period,and rough element height on the flow and pressurization performance of the microchannel were studied from the flow mechanism by the numerical method of the slip boundary.The results show that the factors affecting the thermal transpiration flow on sinusoidal,rectangular,and random walls are the temperature gradient per unit length along the sinusoidal wall path,the low velocity vortices at the depression and the interface,and the temperature gradient per unit length along the random wall path,respectively.The thermal transpiration flow and pressurization performance of sinusoidal and rectangular wall microchannels increase with the increase of roughness element period and decrease with the increase of roughness element height.The ability of sinusoidal rough wall to resist the decrease of pressurization performance is stronger than that of rectangular rough wall under the same roughness element period or height.