TY - CHAP A1 - Lo Piparo, G. B. A1 - Kern, Alexander A1 - Mazzetti, C. T1 - Some masterpoints about risk due to lightning T2 - International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna Y1 - 2012 SN - 978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print) SP - 1 EP - 6 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kern, Alexander A1 - Schelthoff, Christof A1 - Mathieu, Moritz T1 - Calculation of interception efficiencies for mesh-type air-terminations according to IEC 62305-3 using a dynamic electro-geometrical model T2 - International Conference on Lightning Protection (ICLP) : 2 - 7 Sept. 2012, Vienna Y1 - 2012 SN - 978-1-4673-1896-9 (E-Book) ; 978-1-4673-1898-3 (Print) SP - 1 EP - 6 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Pieper, Martin A1 - Klein, Peter T1 - Application of simple, periodic homogenization techniques to non-linear heat conduction problems in non-periodic, porous media JF - Heat mass transfer N2 - Often, detailed simulations of heat conduction in complicated, porous media have large runtimes. Then homogenization is a powerful tool to speed up the calculations by preserving accurate solutions at the same time. Unfortunately real structures are generally non-periodic, which requires unpractical, complicated homogenization techniques. We demonstrate in this paper, that the application of simple, periodic techniques to realistic media, that are just close to periodic, gives accurate, approximative solutions. In order to obtain effective parameters for the homogenized heat equation, we have to solve a so called “cell problem”. In contrast to periodic structures it is not trivial to determine a suitable unit cell, which represents a non-periodic media. To overcome this problem, we give a rule of thumb on how to choose a good cell. Finally we demonstrate the efficiency of our method for virtually generated foams as well as real foams and compare these results to periodic structures. Y1 - 2012 U6 - http://dx.doi.org/10.1007/s00231-011-0879-4 SN - 0947-7411 VL - 48 IS - 2 SP - 291 EP - 300 PB - Springer CY - Berlin ER -