Meinecke, Stefan
Passively mode-locked lasers produce regular optical pulse trains at high repetition rates and find many applications in science and technology. This thesis numerically investigates two specific devices: a monolithically integrated three-section tapered semiconductor quantum-dot laser and a V-shaped external cavity semiconductor laser. Both lasers ...
Kadanik, M. Burgschat, L. Reich, M. Petersen, S. Keßler, O.
Published in
HTM Journal of Heat Treatment and Materials
Heat treatment simulation of inductive surface hardening of large bearing rings is a challenging multi-physical task. Besides the determination of material and process parameters of induction heating, the quenching process must be modelled to obtain realistic results concerning surface hardening depth as well as information about residual stresses ...
Song, Yang
The vortex pump is a kind of impurity pump. Characteristics of vortex pumps are their recessed, semi-open impeller and their enlarged gap between the impeller and the casing. The gap and impeller give the pump a good non-clogging performance. The pump is widely used in transporting sewage water or mixed liquid containing fiber or large particle. Ho...
Morozov, Aleksandr
In the present work, a chemical reaction between a solid and a diffusing constituent is considered. Many experimental observations show a coupling between mechanical stresses and the kinetics at a chemical reaction interface that propagates in a deformable solid. In general, two major processes control the chemical reaction: diffusion of a reactant...
Stoyanov, Todor
The aim of this thesis is to achieve a quality assured and economic production of near-net-shape turbine blades made of titanium aluminide. With this motivation several process parameters, which have an influence on the melting and casting process, were investigated. Furthermore, the topic of direct recycling of TiAl was addressed. Within the scope...
Swienty, Andreas
Die Print-Ausgabe dieser Dissertation erscheint im Verlag Mensch & Buch, ISBN 978-3-9672-9025-7 / Bei der Vor-Ort-Kalibrierung (VOK) von Durchflussmessgeräten mittels Laser-Doppler-Velozimetrie tritt bei gestörten, nicht rotationssymmetrischen Strömungsprofilen eine erhöhte Messunsicherheit auf. Durch die verfahrensbedingte Messung von diskreten St...
Marten, David
Wind turbines are large and complex machines which operate in a highly unsteady environment. Due to the spatially and temporally stochastic nature of the wind resource, a large amount of simulation data is needed when one wants to assess the lifetime of such a machine. Both extreme events, such as storms, strong gusts or significant wind direction ...
El-Sari, B. Biegler, M. Rethmeier, M.
Published in
HTM Journal of Heat Treatment and Materials
Directed energy deposition is a metal additive manufacturing process that builds parts by joining material in a layer-by-layer fashion on a substrate. Those parts are exposed to rapid thermo-cycles which cause steep stress gradients and the layer-upon-layer manufacturing fosters an anisotropic microstructure, therefore stress relief heat treatment ...
Morgenstern, Tino Richter, Daniel Himmel, Jörg Kanoun, Olfa Klöckner, Stephan Wang, Dinan
Published in
tm - Technisches Messen
In prostate surgery the transurethral resection (TURP) represents the gold standard which is based on monopolar (M-TURP) and bipolar techniques (TURis). The investigation of the thermal behavior is one of the most important research topics in this type of surgery procedures. Here monopolar systems have been well investigated. The research on electr...
Martín Herranz, Daniel Elías
Epigenetic clocks are mathematical models that predict the biological age of an organism using DNA methylation data, and which have emerged in the last few years as the most accurate biomarkers of the ageing process. However, little is known about the molecular mechanisms that control the rate of such clocks. In this thesis I focus on the study of ...