SIMPLIFIED ONE-DIMENSIONAL MODEL FOR TRANSIENT TIME-DOMAIN SIMULATION OF CENTRIFUGAL PUMPS

摘要

In the present work a one-dimensional time-domain model of centrifugal pumps is presented. The acoustic excitation and transmission characteristics as well as the steady behaviour of cavitationfree pumps are comprised in this model. Assuming solely plane wave propagation, the pump's acoustic transmission properties are modelled by a reduced one-dimensional representation of the complex impeller and volute geometry. The acoustic excitation consists of the superposition of a monopole and a dipole source in the tongue region at the outlet of the pump. The amplitudes and the phasing of these sources are obtained empirically by means of pressure measurements on the suction and discharge side of the modelled pump. Regarding the steady behaviour, the characteristic curve is included in the model such that, in combination with the piping model of a plant, the respective mean flow conditions are realised in a simulation. Such a model allows integral simulation of the acoustic excitation and transmission characteristics of centrifugal pumps and the system response. Due to the time-domain formulation time-variant behaviour such as opening or closing of valves can be considered. A first validation of the pump model is carried out in an exemplary operating point under cavitation-free conditions.