The study of the possibility of the pumping unit optimization for two operation modes, different from the optimal one

Abstract

BACKGROUND: The study of factors affecting the vibroacoustic characteristics of pumps is one of the main areas of development in the current pump industry. Improvement of these characteristics allows to extend the service life of pumps by means of vibration levels reduction as well as to decrease the noise level.
 AIMS: In this study, the attempt to optimize the flow part of a multi-stage pump was made in order to obtain acceptable noise, vibration and harshness (NVH) characteristics in two operation modes that are different front the optimal one.
 METHODS: As the result of the study, it was found that changing these parameters in favour of NVH has a negative impact on the pump efficiency and vice versa. Thereby the optimal balance between these parameters should be found. The optimization was performed with the method of research of the parameter space with use of LP-tau sequences. The following elements were chosen as the optimization parameters: the area at the entrance to downstream, the angle of guide vanes at the entrance to the downstream, the width of rotor at the outlet, the angle of rotor vanes at the inlet and the outlet, the wrap angle of rotor vane. Decrease of the area of the graph of pressure pulsation spectrum was chosen as the optimization criteria. The mathematical model was verified with two designs of the flow part produced and tested earlier. The first sample has an overstated rate of the NVH spectrum in the area of high frequencies, the second sample has an overstated rate of the NVH spectrum in the area of low frequencies.
 RESULTS: The compiled mathematical model proved its good quality, showing the same results, which allows to speak about the admissibility of its use for optimization of the flow parts of pumps.
 CONCLUSIONS: This study will be useful for specialists in the field of vane hydraulic machines design.