渦巻噴射弁の流量係数 （Ｉ） 渦巻噴射弁構造と流量係数

Abstract

The discharge coefficient (C) of pressure nozzles can be predicted by the nozzle parameters, which are defined by their nozzle geometry. The purpose of this study is to compare the three representative nozzle parameters, “K”, “A'”, and “Δ”. from the viewpoint of practical application.Prediction of “C” by using nozzle Parameter “K” is greatly influenced by the ratio (k=do/ri) of the diameter of swirl insert (do) to the radius of swirl chamber (ri). On the other hand, prediction of “C” by using “A'” or “Δ” does not depend on “k” at the practical range of “k” between 0.2 and 1.0. It was also found that “A'” and “Δ” can be expressed as the function of “K” and “k”, by rearranging their original definitions. Therefore it is considered that “A'” and “Δ” are more widely applicable nozzle parameters.However, inspite of using these suitable nozzle parameters, prediction of “C” is still influhnced by the diameter of the swirl chamber (“di”) itself. It is found that “C” increases with decreasing“di” in the case of atomization of water.