TY - JOUR
TI - Discharge coefficient of small sonic nozzles
AU - Yin Zhao-Qin
AU - Li Dong-Sheng
AU - Meng Jin-Long
AU - Lou Ming
JN - Thermal Science
PY - 2014
VL - 18
IS - 5
SP - 1505
EP - 1510
PT - Article
AB - The purpose of this investigation is to understand flow characteristics in  mini/micro sonic nozzles, in order to precisely measure and control miniscule  flowrates. Experimental and numerical simulation methods have been used to  study critical flow Venturi nozzles. The results show that the nozzle’s size  and shape influence gas flow characteristics which leading the boundary layer  thickness to change, and then impact on the discharge coefficient. With the  diameter of sonic nozzle throat decreasing, the discharge coefficient  reduces. The maximum discharge coefficient exits in the condition of the  inlet surface radius being double the throat diameter. The longer the  diffuser section, the smaller the discharge coefficient becomes. Diffuser  angle affects the discharge coefficient slightly.