Investigation of Characteristics of a Blower Used as an Air Source in an Experimental Rig for Studies of Helical Instabilities in Flowing Fluids

For investigations of aerodynamic properties of helical instabilities in flowing fluids, an experimental rig is currently built [1]. It is intended on the one hand for visualisations of acoustically excited helical structures and on the other hand for model experiments with flows of cyclonal character. As the universal air source for both purposes, a blower is used for which no loading characteristics were available and which, at any rate, is to be operated in some of the regimes at very low Reynolds numbers where one has to expect deviation from characteristics obtained under standard conditions. The authors investigated the blower loading characteristics experimentally and used this opportunity to apply and test practical validity of the general ideas about universal representation of characteristics and criterial similarity parameters of turbomachines, published considerable time ago [2] but seemingly little known and used.