TY - CHAP A1 - Sauerborn, Markus A1 - Klimek, J. A1 - Hoffschmidt, Bernhard A1 - Essen, H. A1 - Sieger, S. A1 - Biegel, G. A1 - Göttsche, Joachim A1 - Hilger, Patrick T1 - Eurosun 2012 : radar technology for heliostat posititon control T2 - Eurosun 2012 : Solar energy for a brighter future : conference proceedings : Rijeka, 18.-22.09.2012 Y1 - 2012 SP - ID 80 CY - Rijeka ER - TY - CHAP A1 - Göttsche, Joachim A1 - Schwarzer, Klemens A1 - Röther, Sascha A1 - Jellinghaus, Sabine A1 - Helten, G. A1 - Wittmann, R. T1 - Efficient daylighting, heating and shading with rooflight heliostats T2 - Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings Y1 - 2009 SP - 243 EP - 246 PB - Ecole Polytechnique Fédérale de Lausanne CY - Lausanne ER - TY - JOUR A1 - Blanke, Tobias A1 - Hagenkamp, Markus A1 - Döring, Bernd A1 - Göttsche, Joachim A1 - Reger, Vitali A1 - Kuhnhenne, Markus T1 - Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates JF - Geothermal Energy N2 - Previous studies optimized the dimensions of coaxial heat exchangers using constant mass fow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar fow types. In contrast, in this study, fow conditions in the circular ring are kept constant (a set of fxed Reynolds numbers) during optimization. This approach ensures fxed fow conditions and prevents inappropriately high or low mass fow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic efort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass fow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellström’s borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefcients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy diference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy fux and hydraulic efort. The Reynolds number in the circular ring is instead of the mass fow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54% of the outer pipe radius for laminar fow and 60% for turbulent fow scenarios. Net-exergetic optimization shows a predominant infuence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth’s thermal properties and the fow type. Conclusively, coaxial geothermal probes’ design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics. Y1 - 2021 U6 - https://doi.org/10.1186/s40517-021-00201-3 SN - 2195-9706 N1 - Corresponding author: Tobias Blanke VL - 9 IS - Article number: 19 PB - Springer CY - Berlin ER - TY - JOUR A1 - Göttsche, Joachim A1 - Schwarzer, Klemens A1 - Röther, S. A1 - Jellinghaus, Sabine T1 - Efficient daylighting, heating and shading with rooflight heliostats JF - Conference Internationale Energie Solaire et Batiment Y1 - 2009 SP - 243 EP - 248 PB - EPFL CY - Lausanne ER - TY - CHAP A1 - Baumann, T. A1 - Teixeira Boura, Cristiano José A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - O'Connell, B. A1 - Schmitz, S. A1 - Zunft, S. T1 - Air/Sand heat exchanger design and materials for solar thermal power plant applications T2 - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 146 EP - 147 PB - Soc. OSC CY - Saint Maur ER - TY - JOUR A1 - Göttsche, Joachim A1 - Gabrysch, K. A1 - Schiller, H. A1 - Kauert, B. A1 - Schwarzer, Klemens T1 - Energetic Effects of demand – controlled ventilation retrofitting in a biochemical laboratory building JF - AIVC publications [Elektronische Ressource] / Air Infiltration and Ventilation Centre Y1 - 2004 N1 - AIVC Conference <25, Prague, 2004> SP - 50 PB - INIVE EEIG CY - Brussels ER - TY - CHAP A1 - Buck, R. A1 - Wurmhöringer, K. A1 - Lehle, R. A1 - Pfahl, A. A1 - Göttsche, Joachim A1 - Meyr, T. T1 - Development of a 30m2 heliostat with hydraulic drive T2 - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 74 EP - 75 PB - Soc. OSC CY - Saint Maur ER - TY - CHAP A1 - Achenbach, Timm A1 - Geimer, Konstantin A1 - Lynen, Arthur A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard T1 - Simulation of thermo-mechanical processes in open volumetric absorber modules T2 - SolarPaces 2012 : concentrating solar power and chemical energy systems : Sept. 11 - 14 2012, Marrakech, Marokko Y1 - 2012 SP - 1 EP - 8 ER - TY - CHAP A1 - Hoffschmidt, Bernhard A1 - Alexopoulos, Spiros A1 - Göttsche, Joachim A1 - Sauerborn, Markus T1 - High concentration solar collectors T2 - Comprehensive renewable energy / ed. Ali Sayigh. Vol. 3: Solar thermal systems: components and applications N2 - Solar thermal concentrated power is an emerging technology that provides clean electricity for the growing energy market. To the solar thermal concentrated power plant systems belong the parabolic trough, the Fresnel collector, the solar dish, and the central receiver system. For high-concentration solar collector systems, optical and thermal analysis is essential. There exist a number of measurement techniques and systems for the optical and thermal characterization of the efficiency of solar thermal concentrated systems. For each system, structure, components, and specific characteristics types are described. The chapter presents additionally an outline for the calculation of system performance and operation and maintenance topics. One main focus is set to the models of components and their construction details as well as different types on the market. In the later part of this chapter, different criteria for the choice of technology are analyzed in detail. KW - Central receiver system KW - Concentrated solar collector KW - Fresnel collector KW - Optical and thermal analysis KW - Solar concentration Y1 - 2012 SN - 978-0-08-087873-7 U6 - https://doi.org/10.1016/B978-0-08-087872-0.00306-1 VL - 3 SP - 165 EP - 209 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Göttsche, Joachim A1 - Reilly, S. A1 - Wittwer, Volker T1 - Advanced window systems and building energy performance / S. Reilly ; J. Göttsche ; V. Wittwer JF - Solar World Congress, 1991 : proceedings of the biennial congress of the International Solar Energy Society, Denver, Colorado, USA, 19-23 August 1991 / ed. by M. E. Arden ... Y1 - 1991 SN - 0-08-041690-X SP - 3211 EP - 3216 PB - Pergamon Press CY - Oxford [u.a.] ER -