G0500-3-5 低レイノルズ数における臨海ノズルの形状の研究([G0500-3]流体工学部門一般講演(3))

Abstract

For toroidal throat Venturi nozzles with various diffuser lengths and half angles, their critical back pressure ratio were experimentally investigated on the theoretical Reynolds number less than 2×10^4. The results showed that the diffuser shapes provided in JIS Z 8767(2006) are not always adequate for flow measurement under the above Reynolds number range. Finally, when the toroidal throat Venturi nozzle is used on flow measurements, its diffuser length is desirable to be longer than lOd and its diffuser half angle should be around 3.5 degrees.