@article{GoettscheGabryschSchilleretal.2004, author = {G{\"o}ttsche, Joachim and Gabrysch, K. and Schiller, H. and Kauert, B. and Schwarzer, Klemens}, title = {Energetic Effects of demand - controlled ventilation retrofitting in a biochemical laboratory building}, series = {AIVC publications [Elektronische Ressource] / Air Infiltration and Ventilation Centre}, journal = {AIVC publications [Elektronische Ressource] / Air Infiltration and Ventilation Centre}, publisher = {INIVE EEIG}, address = {Brussels}, pages = {50}, year = {2004}, language = {en} } @article{GoettscheGabryschDelahayeetal.2002, author = {G{\"o}ttsche, Joachim and Gabrysch, K. and Delahaye, A. and Schwarzer, Klemens}, title = {Solar-Campus Juelich - Energy performance and indoor climate}, series = {AIVC 23rd conference - EPIC 2002 AIVC (in conjunction with 3rd European Conference on Energy Performance and Indoor Climate in Buildings) - 23-26 October 2002 - Lyon - France - vol 2}, journal = {AIVC 23rd conference - EPIC 2002 AIVC (in conjunction with 3rd European Conference on Energy Performance and Indoor Climate in Buildings) - 23-26 October 2002 - Lyon - France - vol 2}, pages = {381 -- 386}, year = {2002}, language = {en} } @article{GoettscheAlexopoulosDuemmleretal.2019, author = {G{\"o}ttsche, Joachim and Alexopoulos, Spiros and D{\"u}mmler, Andreas and Maddineni, S. K.}, title = {Multi-Mirror Array Calculations With Optical Error}, pages = {1 -- 6}, year = {2019}, abstract = {The optical performance of a 2-axis solar concentrator was simulated with the COMSOL Multiphysics® software. The concentrator consists of a mirror array, which was created using the application builder. The mirror facets are preconfigured to form a focal point. During tracking all mirrors are moved simultaneously in a coupled mode by 2 motors in two axes, in order to keep the system in focus with the moving sun. Optical errors on each reflecting surface were implemented in combination with the solar angular cone of ± 4.65 mrad. As a result, the intercept factor of solar radiation that is available to the receiver was calculated as a function of the transversal and longitudinal angles of incidence. In addition, the intensity distribution on the receiver plane was calculated as a function of the incidence angles.}, language = {en} } @article{Goettsche1994, author = {G{\"o}ttsche, Joachim}, title = {Eldorado summer schools}, series = {Progress in solar energy education. 3 (1994)}, journal = {Progress in solar energy education. 3 (1994)}, isbn = {1018-5607}, pages = {31 -- 33}, year = {1994}, language = {en} } @article{GorzalkaSchmiedtSchorn2021, author = {Gorzalka, Philip and Schmiedt, Jacob Estevam and Schorn, Christian}, title = {Automated Generation of an Energy Simulation Model for an Existing Building from UAV Imagery}, series = {Buildings}, volume = {11}, journal = {Buildings}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2075-5309}, doi = {10.3390/buildings11090380}, pages = {15 Seiten}, year = {2021}, abstract = {An approach to automatically generate a dynamic energy simulation model in Modelica for a single existing building is presented. It aims at collecting data about the status quo in the preparation of energy retrofits with low effort and costs. The proposed method starts from a polygon model of the outer building envelope obtained from photogrammetrically generated point clouds. The open-source tools TEASER and AixLib are used for data enrichment and model generation. A case study was conducted on a single-family house. The resulting model can accurately reproduce the internal air temperatures during synthetical heating up and cooling down. Modelled and measured whole building heat transfer coefficients (HTC) agree within a 12\% range. A sensitivity analysis emphasises the importance of accurate window characterisations and justifies the use of a very simplified interior geometry. Uncertainties arising from the use of archetype U-values are estimated by comparing different typologies, with best- and worst-case estimates showing differences in pre-retrofit heat demand of about ±20\% to the average; however, as the assumptions made are permitted by some national standards, the method is already close to practical applicability and opens up a path to quickly estimate possible financial and energy savings after refurbishment.}, language = {en} } @article{ElMoussaouiTalbiAtmaneetal.2020, author = {El Moussaoui, Noureddine and Talbi, Sofian and Atmane, Ilyas and Kassmi, Khalil and Schwarzer, Klemens and Chayeb, Hamid and Bachiri, Najib}, title = {Feasibility of a new design of a Parabolic Trough Solar Thermal Cooker (PSTC)}, series = {Solar Energy}, volume = {201}, journal = {Solar Energy}, number = {Vol. 201 (May 2020)}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0038-092X}, doi = {10.1016/j.solener.2020.03.079}, pages = {866 -- 871}, year = {2020}, abstract = {In this article, we describe the structure, the functioning, and the tests of parabolic trough solar thermal cooker (PSTC). This oven is designed to meet the needs of rural residents, including Urban, which requires stable cooking temperatures above 200 °C. The cooking by this cooker is based on the concentration of the sun's rays on a glass vacuum tube and heating of the oil circulate in a big tube, located inside the glass tube. Through two small tubes, associated with large tube, the heated oil, rise and heats the pot of cooking pot containing the food to be cooked (capacity of 5 kg). This cooker is designed in Germany and extensively tested in Morocco for use by the inhabitants who use wood from forests. During a sunny day, having a maximum solar radiation around 720 W/m2 and temperature ambient around 26 °C, maximum temperatures recorded of the small tube, the large tube and the center of the pot are respectively: 370 °C, 270 °C and 260 °C. The cooking process with food at high (fries, ..), we show that the cooking oil temperature rises to 200 °C, after 1 h of heating, the cooking is done at a temperature of 120 °C for 20 min. These temperatures are practically stable following variations and decreases in the intensity of irradiance during the day. The comparison of these results with those of the literature shows an improvement of 30-50 \% on the maximum value of the temperature with a heat storage that could reach 60 min of autonomy. All the results obtained show the good functioning of the PSTC and the feasibility of cooking food at high temperature (>200 °C).}, language = {en} } @article{DerschGeyerHerrmannetal.2004, author = {Dersch, J{\"u}rgen and Geyer, Michael and Herrmann, Ulf and Jones, Scott A. and Kelly, Bruce and Kistner, Rainer and Ortmanns, Winfried and Pitz-Paal, Robert and Price, Henry}, title = {Trough integration into power plants—a study on the performance and economy of integrated solar combined cycle systems}, series = {Energy : the international journal}, volume = {29}, journal = {Energy : the international journal}, number = {5-6 (Special Issue SolarPaces)}, issn = {0360-5442}, doi = {10.1016/S0360-5442(03)00199-3}, pages = {947 -- 959}, year = {2004}, language = {en} } @article{DammSauerbornFendetal.2017, author = {Damm, Marc Andr{\´e} and Sauerborn, Markus and Fend, Thomas and Herrmann, Ulf}, title = {Optimisation of a urea selective catalytic reduction system with a coated ceramic mixing element}, series = {Journal of ceramic science and technology}, volume = {8}, journal = {Journal of ceramic science and technology}, number = {1}, publisher = {G{\"o}ller}, address = {Baden-Baden}, isbn = {2190-9385 (Print)}, issn = {2190-9385 (Online)}, doi = {10.4416/JCST2016-00056}, pages = {19 -- 24}, year = {2017}, language = {en} } @article{BlankeHagenkampDoeringetal.2021, author = {Blanke, Tobias and Hagenkamp, Markus and D{\"o}ring, Bernd and G{\"o}ttsche, Joachim and Reger, Vitali and Kuhnhenne, Markus}, title = {Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates}, series = {Geothermal Energy}, volume = {9}, journal = {Geothermal Energy}, number = {Article number: 19}, publisher = {Springer}, address = {Berlin}, issn = {2195-9706}, doi = {10.1186/s40517-021-00201-3}, pages = {23 Seiten}, year = {2021}, abstract = {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 Hellstr{\"o}m'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.}, language = {en} } @article{AlexopoulosHoffschmidt2017, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard}, title = {Advances in solar tower technology}, series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, volume = {6}, journal = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2041-840X}, doi = {10.1002/wene.217}, pages = {1 -- 19}, year = {2017}, language = {en} }