Robert Hausner

AEE - Institute for Sustainable Technologies | AEE INTEC

In this paper, the major challenges of in-situ collector array testing are analyzed and a framework to address them is developed. The study of the challenges is based on theoretical investigations as well as on data evaluations of a solar district heating (SDH) plant which was equipped with high-precision measurement equipment.

A major basic problem in selecting appropriate polymeric materials and processing technology routes is related to the lack of well-defined functional and performance requirements on the component level and to material property requirements on the specimen level.

For the utilization of polymeric materials in high-demanding applications like solar thermal systems it is of utmost importance to define the performance requirements and to investigate the applicability of components for defined systems under service relevant conditions. This paper deals with the lifetime estimation of black-pigmented polypropylen...

Introduction Materials and Sample Preparation Physical Characterization of the Polymers Results and Discussion Effect of Thermotropic Layers on Collector Efficiency and Stagnation Temperatures Outlook References

This paper focuses on the effect of material composition on the overheating protection properties of thermotropic systems with fixed domains for solar thermal collectors. Numerous functional layers were prepared by a variation of base resin (polyester-, epoxy- or urethane–acrylate) and of thermotropic additives (non-polar and polar waxes) as well a...

The main objective of the present study was to evaluate the potential of thermotropic layers to provide overheating protection in solar collectors by theoretical modeling of an all-polymeric solar panel. For that purpose model calculations were carried out to determine the effects of thermotropic glazings on overall solar collector performance and...

Within this study the potential of thermotropic layers to prevent overheating of an all-polymeric solar collector is evaluated by theoretical modeling. The investigations show that collector stagnation temperatures can be reduced to temperatures between 80 and 90°C by using thermotropic layers either in the glazing or on the absorber. For overheati...

For the application demonstration of cellulose triacetate (CTA) polymer film based transparent insulation (TI) structures a technically and ecologically optimized TI facade system was developed and used to equip a south-oriented wall of a solar house meeting passive house standard in Graz, Austria. The demonstration building was equipped with an ap...

1. BACKGROUND The development of an efficient and cost-effective heat storage is still one of the major technical challenges for the widespread use of solar thermal energy for space heating. Up to now solar heat has been stored mostly in well insulated water tanks. The volume of these tanks is as large as 3 m³ for relatively high solar fractions an...

In this paper, the results of a research and demonstration project to develop and optimize a transparent insulation (TI) wall heating system are described. First, the overall research and development concept and details of the modelling and optimization of the TI structure with regard to polymer type and cell geometry are described. Second, this pa...

The stagnation procedure generally can be divided into five typical phases. In phases where steam occurs energy is transported very effectively from the collector to other system components and leads to high temperature loads. Solar systems should be constructed in such a way that at the end of the phase where liquid is pushed out of the collector...

It is generally accepted that the heat transfer from the fluid tube of a fin absorber to the fluid itself, depends to a great extent on the flow condition. Laminar flow, as compared to turbulent flow, can result in a considerable loss in efficiency which could often be avoided by the appropriate design of the absorber and the absorber arrangement i...

Sodium Calcium Magnesium Silicate, Na2Ca4Mg2Si4O15, has been investigated by means of X-ray powder diffraction. Data were obtained by a conventional diffractometer. Unit cell dimensions were determined by an indexing program. A monoclinic cell was found, a = 17.884(2) Å, b = 5.3573(8) Å, c = 7.1796(8) Å, β = 112.71 (1)°; V=634.56 A3.

Sodium Calcium Magnesium Silicate, Na2Ca4Mg2Si4O15, has been investigated by means of X-ray powder diffraction. Data were obtained by a conventional diffractometer. Unit cell dimensions were determined by an indexing program. A monoclinic cell was found, a = 17.884(2) Å, b = 5.3573(8) Å, c = 7.1796(8) Å, β = 112.71 (1)°; V=634.56 A3.

Pore-size distribution curves for granular materials, obtained by mercury porosimetry, are influenced by the roughness of the grain surface and the interstitial space. It is shown that the pore space associated with the surface roughness is approximately proportional to R** minus **1 (R equals mean grain radius) and must be regarded as part of the...

In the paper we report on our joint efforts to perform an ecological and energetic evaluation of different transparent insulation systems. Solar gains have been calculated for different climatic zones in Austria, for different house types and orientations. The ecological evaluation of the systems is based on the methode of Life-Cycle-Assessment usi...