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Aus Der Wiesche S.,Muenster University of Applied science
Proceedings of the ASME Turbo Expo | Year: 2012

It is widely considered that micro gas turbines are potential devices for future energy needs. However, many micro gas turbine development projects have failed, particularly those with a very low power level below 10 kW. The financial and experimental capabilities for micro gas turbine development projects are typically extremely limited; hence there is a need for low cost mobile test rigs. To close this gap, a robust mobile test rig for turbo-shaft micro gas turbines was developed and validated. The shaft power can be determined using a thermal measurement approach. This circumvents any issues associated with high voltage and electric current levels. The shaft power can be obtained by a straightforward parameter identification procedure based on simple temperature measurements. This approach is feasible because an analytical expression for the transient temperature field can be obtained. The test rig and thermal power measurement concept were fully validated with a commercial micro gas turbine; good agreement was obtained between the experimental results and the theoretical process data. Copyright © 2012 by ASME. Source

Banos O.,University of Granada | Villalonga C.,CGI Spain | Damas M.,University of Granada | Gloesekoetter P.,Muenster University of Applied science | And 2 more authors.
Scientific World Journal | Year: 2014

Technological advances on the development of mobile devices, medical sensors, and wireless communication systems support a new generation of unobtrusive, portable, and ubiquitous health monitoring systems for continuous patient assessment and more personalized health care. There exist a growing number of mobile apps in the health domain; however, little contribution has been specifically provided, so far, to operate this kind of apps with wearable physiological sensors. The PhysioDroid, presented in this paper, provides a personalized means to remotely monitor and evaluate users' conditions. The PhysioDroid system provides ubiquitous and continuous vital signs analysis, such as electrocardiogram, heart rate, respiration rate, skin temperature, and body motion, intended to help empower patients and improve clinical understanding. The PhysioDroid is composed of a wearable monitoring device and an Android app providing gathering, storage, and processing features for the physiological sensor data. The versatility of the developed app allows its use for both average users and specialists, and the reduced cost of the PhysioDroid puts it at the reach of most people. Two exemplary use cases for health assessment and sports training are presented to illustrate the capabilities of the PhysioDroid. Next technical steps include generalization to other mobile platforms and health monitoring devices. © 2014 Oresti Banos et al. Source

Aus Der Wiesche S.,Muenster University of Applied science
Proceedings of the ASME Turbo Expo | Year: 2014

Based on a voice-of-the-industry survey covering major turbine manufactures as well as power plant owners and operators an undergraduate course on gas and steam turbines was developed at Muenster University of Applied Sciences. This course is also supported by cost-efficient experiments. The experimental investigations on laboratory test rigs are making the students more familiar with turbomachinery phenomena like gas turbine cycle performance, fundamental rotordynamics, blade vibrations, and flow through turbine cascades and loss correlations. The experiments and test rigs were developed in great part by students as part of their Bachelor or Master theses. Furthermore, the experiments did not require tremendous efforts or an expensive infrastructure; they were operated in typical University laboratory environments. Copyright © 2014 by ASME. Source

Albers K.,Muenster University of Applied science | Wittrock U.,Muenster University of Applied science
Applied Physics B: Lasers and Optics | Year: 2011

Efficient quasi-three-level laser operation requires the generation of the highest possible pump rate from a given pump source. We derive the fundamental scaling laws for the pump rate and we extract optimization criteria for pump concepts from these laws. The analysis is then applied to the thin-disk laser. Based on the results, a novel pump concept for thin-disk lasers is proposed, which allows for several tens of pump beam passes and reduces the optical complexity of conventional pump concepts. Furthermore, the beam quality of the pump source is preserved almost completely, facilitating the highest possible pump rate. © 2011 Springer-Verlag. Source

Scholz T.,Muenster University of Applied science | Dickmann K.,Muenster University of Applied science | Ostendorf A.,Ruhr University Bochum
Physics Procedia | Year: 2013

New developments and characteristics of high brilliant laser sources have led to new applications in the field of laser remote processing. Due to high particle formation rates within the vapor plume, a significant influence of the interaction between laser radiation and nanoparticles on the process may occur. The presented work shows results of the investigation of the dynamical formation of nanoparticles within the vapor plume during the welding of stainless steel with a 2 kW Multi-Mode fiber laser under laser remote conditions. The particle size distribution is measured by the evaluation of TEM-images, whereas, the plasma temperature and particle density are analyzed in dependence of the irradiation time. © 2013 The Authors. Source

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