One of the main options to drive the cost of parabolic trough collectors (PTCs) technology down is to reduce the size of the solar field. This work proposes a novel receiver longitudinally undulated as a replacement for the conventional straight tube and investigates the effects on the size of absorbers, PTC modules and entire solar field. For this purpose, the developed method based on the similitude analysis should provide tools for drawing a comparison between the various designs of the absorber and should give useful measures of the scenario of their commissioning. Undulated absorber in service and without added supplementary mechanical components; the size of a solar collector field should reduce about ~29.5% consequence of the reduced size of the solar collector module and the absorber. The increase of the pressure drops through the novel absorber pipe should be re-balanced by the reduction in its size.
One of the main options to drive the cost of parabolic trough collectors (PTCs) technology down is to reduce the size of the solar field. This work proposes a novel receiver longitudinally undulated as a replacement for the conventional straight tube and investigates the effects on the size of absorbers, PTC modules and entire solar field. For this purpose, the developed method based on the similitude analysis should provide tools for drawing a comparison between the various designs of the absorber and should give useful measures of the scenario of their commissioning. Undulated absorber in service and without added supplementary mechanical components; the size of a solar collector field should reduce about ~29.5% consequence of the reduced size of the solar collector module and the absorber. The increase of the pressure drops through the novel absorber pipe should be re-balanced by the reduction in its size
Over the past few years, multicore systems have become increasingly powerful and thereby very useful in high-performance computing. However, many applications, such as some linear algebra algorithms, still cannot take full advantage of these systems. This is mainly due to the shortage of optimization techniques dealing with irregular control structures. In particular, the well-known polyhedral model fails to optimize loop nests whose bounds and/or array references are not affine functions. This is more likely to occur when handling sparse matrices in their packed formats. In this article, we propose using 2d-packed layouts and simple affine transformations to enable optimization of triangular and banded matrix operations. The benefit of our proposal is shown through an experimental study over a set of linear algebra benchmarks.
In this work, an optimization study of the delivered power density by the solid oxide fuel cells is presented according to a thermodynamic model. The power density is defined by the current density, the Nernst potential and the three losses: concentration, activation and ohmic. A comparison between the Tafel and Butler-Volmer formulations was performed to quantify the activation loss. A program in FORTRAN language was developed locally for the resolution of the mathematical equations representing the used physical model. The obtained results show that the SOFCs power density is inversely proportional to the anode thickness, electrolyte thickness and cathode thickness. The optimum fuel water content ensures the maximum power density is 6.25%. The cell power density is proportional to the oxygen concentration in the oxidant, the operating temperature and the operating pressure.