Jens Müller

Ruhr-Universität Bochum | RUB · Department of Mechanical Engineering

This contribution studies the impact of the rotor-stator interaction in a single-stage progressing cavity pump on the flow rate and pressure. Specifically, we investigate the effect of the rotor movement on the sealings formed with deformable stators for various speeds and pressures. Sealings are reconstructed with the help of a geometric 3D model....

This contribution studies the impact of the rotor-stator interaction in a single-stage progressing cavity pump on the flow rate and pressure. Specifically, we investigate the effect of the rotor movement on the sealings formed with deformable stators for various speeds and pressures. Sealings are reconstructed with the help of a geometric 3D model....

The wear and failure of pin joints integrated in coupling rods of process equipment can lead to unpredictable breakdown with severe consequences. We present a simple algorithm for a non-invasive online detection of wear in pin joints where a progressing cavity pump serves as an example. The algorithm only requires a pressure sensor and a binary spe...

We present a model-based approach for a non-invasive online wear detection for progressing cavity pumps. The approach is based on a model of the rotor displacement. All unknown model parameters can be determined from measured data with a recursive-least-squares algorithm, which can efficiently be run on an embedded device. The identified model para...

We introduce a new method for torque and speed estimation of induction motors under voltage/frequency (V/f) open-loop control. In contrast to existing approaches that need the phase current, the proposed algorithm only requires the effective value (root mean square) of the stator current and the synchronous frequency, which are usually available fr...

We interpret the problem of synchronizing multiple coupled laser diodes as a robust stabilization problem. We show that mathematical optimization, specifically constrained nonlinear programming, can be applied to identify stable and robust points of operation with optimal intensities. In contrast to existing methods, the method proposed here does n...