@misc{SchachtHausdorfWunderle, author = {Schacht, Ralph and Hausdorf, Alexander and Wunderle, Bernhard}, title = {Feasibility and Design Study of a Frictionless Air Mover for Thermal Management of Electronics}, series = {Journal of Physics: Conference Series}, volume = {525}, journal = {Journal of Physics: Conference Series}, issn = {1742-6596}, doi = {10.1088/1742-6596/525/1/012026}, pages = {012026}, abstract = {A frictionless air mover concept will be introduced. As opposed to a piezoelectric driven fan, the air mover is based on a flexible blade whose vibration is driven by means of a magnetic field. The blade material is based on a polymer material. The paper presents the results of feasibility and an on-going comprehensive design study. The results are compared with a comparable piezoelectric fan [1, 2]. The performance of the feasibility study amounted to 65\% to the piezoelectric fan. To enhance the performance, two different blade materials as well as the influence of the coil shape and value were under investigation. A further goal is to reduce the size and to investigate the influence of a cabinet. The design study results in a prototype of a size of 50 x 14 x 35 mm² incl. a cabinet. The performance could be doubled. A volume flow rate of V̊ ~14 l/min and static pressure of Ƿstat = 3 Pa could be reached.}, language = {en} } @inproceedings{SchachtHausdorfWunderleetal., author = {Schacht, Ralph and Hausdorf, Alexander and Wunderle, Bernhard and Rzepka, Sven and Michel, Bernd}, title = {Efficiency optimization for a frictionless air flow blade fan - design study}, series = {14th IEEE ITHERM Conference, Orlando(Fl), USA, May 30th, 2014}, booktitle = {14th IEEE ITHERM Conference, Orlando(Fl), USA, May 30th, 2014}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4799-5267-0}, pages = {1019 -- 1026}, abstract = {This paper resumes the frictionless fan concept which was introduced at itherm 2012 [1]. This concept was based on a flexible polymer blade, the vibration of which is, as opposite to the piezoelectric driven fan principle, driven by means of a magnetic field. This type of fan can be of interest in regions where otherwise the fluid flow would be stagnant. This paper presents the results of a further in depth design study to reduce power loss and form factor as well as to optimize fan efficiency. Therefore, different blade materials and shapes, different sheet materials for the inductive stimulation as well as the influence of coil shape, value and number were under investigation. As a result, the size could be reduced by half and the efficiency could be doubled. A maximum flow rate of 14 l/min and a static pressure of 3 Pa at 240 mW fan power could be reached.}, language = {en} } @misc{SparrHausdorfJeskeetal., author = {Sparr, Holger and Hausdorf, Alexander and Jeske, Peter and Kale, Nachiket and Schacht, Ralph and Ziegenhorn, Matthias and Zysk, Oliver}, title = {±270 VDC Aircraft Harness Structural Analysis}, series = {Procedia Engineering}, volume = {114}, journal = {Procedia Engineering}, issn = {1877-7058}, doi = {10.1016/j.proeng.2015.08.078}, pages = {346 -- 353}, abstract = {This research focuses on the structural analysis of aircraft electrical harnesses for the 270 VDC network. A combined experimental and simulation-based approach is used, where numerical models for the harnesses are developed and experimental data are acquired for basic test cases (steady load, pendulum test, etc.) as well as for different vibration load cases. Validation of the numerical models is done using the preliminary experimental data, resulting in a mature refined model in order to simulate complex scenarios. The goal of the project is thus to develop a suite of tools that allows detailed structural analysis of the aircraft harnesses, both stand alone as well as in combination with other systems}, language = {en} }