Agglomeration represents an important particle formation process used in many industries. One particularly attractive process setup is continuous fluidized bed spray agglomeration, which features good mixing as well as high heat and mass transfer on the one hand and constant product throughput with constant quality as well as high flow rates compared to batch mode on the other hand. Particle properties such as agglomerate size or porosity significantly affect overall product properties such as re-hydration behavior and dissolubility. These can be influenced by different operating parameters. In this manuscript, a population balance model for a continuous fluidized bed spray agglomeration is presented and adapted to experimental data. Focus is on the description of the dynamic behavior in continuous operation mode in a certain neighborhood around steady-state. Different kernel candidates are evaluated and it is shown that none of the kernels are able to match the first six minutes with time independent parameters. Afterwards, a good fit can be obtained, where the Brownian and the volume independent kernel models match best with the experimental data. Model fit is improved for identification on a shifted time domain neglecting the initial start-up phase. Here, model identifiability is shown and parameter confidence intervals are computed via parametric bootstrap.
This paper is concerned with control-based damping of friction-induced self-excited oscillations that appear in electromechanical systems with an elastic shaft. This approach does not demand additional oscillations measurements or an observer design. The control system provides the angular velocity and damping control via the combination of a parallel feed-forward compensator (PFC) and adaptive -tracking feedback control. The PFC is designed to stabilize the zero dynamics of an augmented system and renders it almost strict positive real (ASPR). The proposed control approach is tested in simulations.
In this article control-based reduction of gantry crane elastic swinging in the trolley travel direction is concerned. As acceleration forces of the trolley are often the reason of these vibrations, they can be utilized in an appropriate damping strategy. For an elastic crane a dynamic model is derived applying the finite element method (FEM). This approach results in a high order state-space model, which should be reduced for the controller design procedure. In order to design a controller, which can be applied for simultaneous damping of elastic vibrations of crane construction and payload sway with varying rope length a robust control approach has been applied.