Xylem has over 23000 people working towards a common goal: to create innovative solutions for the world’s water needs. By developing new technologies, we improve the way water is used, stored and reused now and in the future. We transport, purify, analyze and return water to nature and help people use water efficiently – at home, at work, in industry and in agriculture.

We have more than 100 years of experience in the field of water technology and offer a portfolio of leading product brands and expertise in a wide range of applications. Our expertise has led to long-term relationships with our customers in more than 150 countries. In 2022, Xylem had a turnover of 5.5 billion dollars. One of Xylem’s product categories is Flygt’s pumps, which are based on rotating systems and with that comes challenges around vibrations. The department for Mechanics and Materials at Xylem’s Sundbyberg office is developing models to facilitate vibration prediction.

Student thesis proposal
Vibration analysis of Flygt’s pumps is done by Mechanics and Materials division which is part of the Research and Development department in Sundbyberg office. The analysis includes both simulation and experiments, and the group is aiming to further develop models to predict vibration and improve the dynamic behavior of the products.

Experiments have shown that the surrounding water in a pump basin affects the eigenfrequencies of the system. CFD can be used to model and evaluate the effect of the surrounding water, but it is very complex and computationally expensive. A more efficient way is to use an acoustic pressure model which is normally used for sound analysis. This method has been used in other research areas to account for the effect of “added water mass” with good results.

The finite element software used by the group is COMSOL Multiphysics. The thesis work consists of developing and evaluating the accuracy of a COMSOL Multiphysics solid-acoustic model for complex 3D structures with rotatin