Study of Choked Flows through a Convergent Nozzle  

作　　者：Kazunori KUBO Yoshiaki MIYAZATO Kazuyasu MATSUO 

机构地区：[1]Department of Mechanical Systems Engineering,Faculty of Environmental Engineering,The University of Kitakyushu,1-1 Hibikino,Wakamatsu-ku,Kitakyushu City,808-0135,Japan

出　　处：《Journal of Thermal Science》2010年第3期193-197,共5页热科学学报（英文版）

摘　　要：When sonic nozzles of significantly smaller diameter are used as standard flow meters,the critical back pressure ratio is affected by the boundary layer at the nozzle throat.However,the effect of the boundary layer on choking criteria is still controversial.Then,the choking phenomenon of a convergent nozzle flow has been experimentally investigated using four convergent nozzles with the same diameter followed by a straight pipe of a variable length.As a result,it is shown that the critical back pressure ratio is smaller than that for the steady one-dimensional is-entropic flow and decreases as the boundary layer thickness increases.Moreover,the main flow Mach number at the nozzle exit is supersonic when the back pressure ratio is equivalent to the choking condition,and the Mach number increases as the boundary layer thickness increases.

关 键 词：Boundary Layer Convergent Nozzle Choked Flow Choking Pressure Ratio 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]