Production of clean renewable energy is one of the main challenges for science and society in the near future to incorporate a more sustainable power economy. One promising technique are Concentrated Solar Power (CSP) systems, particularly solar tower plants. They concentrate solar radiation onto a central location, called receiver, by using mirrors that automatically adjust to the position of the sun. This type of power plant is also called Central Receiver System (CRS).

Figure: Almeria tower power plant 

[ Quelle: DLR (CC-BY 3.0) ]

At this central receiver high temperatures can be realized which are used to drive a power cycle to generate electricity. To further increase the efficiency of such CRS and consequently make them more economically and ecologically attractive the use of liquid metals as a new heat transfer fluid is investigated. At the Karlsruhe Liquid Metal LAboratory (KALLA) on KIT Campus North such a test facility will be build (see)

Figure: Picture of thermal boundary conditions

For numerical simulations the location where the sunlight is concentrated, the receiver, is very interesting. Due to design of the power plant this receiver experiences a complex thermal boundary condition because the irradiation is neither homogeneous in circumferential direction nor in axial direction. Together with the fact that liquid metals are used as high temperature fluid, simulations become truly challenging.