TY  - JOUR
A1  - Hennecke, Klaus
A1  - Schwarzbözl, Peter
A1  - Hoffschmidt, Bernhard
A1  - Göttsche, Joachim
A1  - Koll, G.
A1  - Beuter, M.
A1  - Hartz, T.
T1  - The solar power tower Jülich – a solar thermal power plant for test and demonstration of air receiver
JF  - Solar energy and human settlement : Elektronische Ressource : proceedings of ISES world congress 2007 ; (Vol. I - Vol. V) / [ISES Solar World Congress. ISES, International Solar Energy Society]. D. Yogi Goswami ; Yuwen Zhao
Y1  - 2007
SN  - 978-7-302-16146-2
N1  - Solar World Congress <2007, Beijing> ; International Solar Energy Society
SP  - 1749
EP  - 1753
PB  - Tsinghua Univ. Press
CY  - Beijing
ER  - 
TY  - JOUR
A1  - Sattler, Johannes, Christoph
A1  - Röger, Marc
A1  - Schwarzbözl, Peter
A1  - Buck, Reiner
A1  - Macke, Ansgar
A1  - Raeder, Christian
A1  - Göttsche, Joachim
T1  - Review of heliostat calibration and tracking control methods
JF  - Solar Energy
N2  - Large scale central receiver systems typically deploy between thousands to more than a hundred thousand heliostats. During solar operation, each heliostat is aligned individually in such a way that the overall surface normal bisects the angle between the sun’s position and the aim point coordinate on the receiver. Due to various tracking error sources, achieving accurate alignment ≤1 mrad for all the heliostats with respect to the aim points on the receiver without a calibration system can be regarded as unrealistic. Therefore, a calibration system is necessary not only to improve the aiming accuracy for achieving desired flux distributions but also to reduce or eliminate spillage. An overview of current larger-scale central receiver systems (CRS), tracking error sources and the basic requirements of an ideal calibration system is presented. Leading up to the main topic, a description of general and specific terms on the topics heliostat calibration and tracking control clarifies the terminology used in this work. Various figures illustrate the signal flows along various typical components as well as the corresponding monitoring or measuring devices that indicate or measure along the signal (or effect) chain. The numerous calibration systems are described in detail and classified in groups. Two tables allow the juxtaposition of the calibration methods for a better comparison. In an assessment, the advantages and disadvantages of individual calibration methods are presented.
Y1  - 2020
U6  - http://dx.doi.org/10.1016/j.solener.2020.06.030
VL  - 207
SP  - 110
EP  - 132
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Schwager, Christian
A1  - Flesch, Robert
A1  - Schwarzbözl, Peter
A1  - Herrmann, Ulf
A1  - Teixeira Boura, Cristiano José
T1  - Advanced two phase flow model for transient molten salt receiver system simulation
JF  - Solar Energy
N2  - In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed.
KW  - Molten salt solar tower
KW  - Molten salt receiver system
KW  - Dynamic simulation
KW  - Two-phase modelling
KW  - Transient flux distribution
Y1  - 2022
U6  - http://dx.doi.org/10.1016/j.solener.2021.12.065
SN  - 0038-092X (print)
SN  - 1471-1257 (online)
VL  - 232
SP  - 362
EP  - 375
PB  - Elsevier
CY  - Amsterdam
ER  -