Ju-Han Lee

Performance comparison of dish solar collector system with mirror arrays and receiver shapes

The thermal performance comparisons of the dish solar collector system are numerically investigated with mirror arrays and receiver shapes. In order to compare the performances of the dish solar collector systems, six different mirror arrays and four different receiver shapes are considered and the radiative heat flux distribution on the inside of the receiver is analysed. The solar irradiation reflected by mirrors is traced using the Monte-Carlo method. The results show that the dome type has the best performance in receiver shapes and the 2AND4INLINE has the best performance in mirror arrays except the perfect mirror.

Characteristics of Heat Transfer and Pressure Loss of the Porous Materials for a Solar Volumetric Air Receiver

Characteristics of heat transfer and pressure loss of fills for solar volumetric air receivers are experimentally investigated with the material and the thickness. In order to analyze the characteristics of heat transfer of the fills, the solar volumetric air receiver considered in this paper consists of a ceramic tube and fills inserted in the ceramic tube. Two materials, which are honeycomb (diameter: 100 mm, thickness: 300 mm and laminated mesh (diameter: 100 mm, thickness: 1 mm), are considered as the fills. This receiver is heated by an electric heater. The inner air temperatures of the ceramic tube are measured by thermocouples, which are installed at each layer of the ceramic tube. In order to study the pressure loss of the fills, the experimental apparatus, which is similar to the above experiment, is fabricated. An acrylic tube is used like as the ceramic tube of the above experiment. The pressure losses of the fills inserted in the acrylic tube are measured between front and rear of those by transmitter with the Reynolds number. The results show that the heat transfer and pressure loss characteristics of the laminated mesh are superior to those of the honeycomb.