Action of the Fluid in the Air-Micrometer : 3rd Report, Characteristics of Double-Disc Nozzle No. 1, In the Case of Compressibility Being Ignored

抄録

Experiments were carried out on 11 types of straight-edged nozzles and 11 types of roundedged nozzles which have an inner diameter of about 2 mm. These are the nozzles used for the air-micrometer, and the experiments were carried out in the case of the ratio of gap and inner diameter up to 0.1 using distilled water up to 3 m head and using low pressure air up to 500 mmAq differential pressure, and the discharge characteristics were investigated. The results are summarized as follows : 1. Excepting the friction loss and the discharged velocity energy loss, the additional loss of head which had not been clear was determined. 2. The values calculated using this result agree very well with the measured ones. So, unlike the former characteristic equations, the characteristics of double-disc nozzle with a large gap can be accurately calculated, especialy when the nozzle is sharp-edged.