Model and simulation of a solar kiln with energy storage

A solar kiln with energy storage can be used for continuous drying. This kiln consisted of several units which were modeled to simulate it in operation. A model was proposed for each unit, and another based on laboratory tests for drying a wooden board by passing air across. These models were combined to produce a global model. Simulation results were then analyzed and showed that the use of storage was justified to reduce drying time. Moreover, with the judicious use of storage and air renewal, drying schedules could be produced for a better quality of dried wood

An oriented-design simplified model for the efficiency of a flat plate solar air collector

In systems design, suitably adapted physical models are required. Different modelling approaches for a solar air collector were studied in this paper. First, a classical model was produced, based on a linearization of the conservation of energy equations. Its resolution used traditional matrix methods. In order to improve the possibilities for use in design, the behaviour of the collector was next expressed in terms of efficiency. Lastly, simplified models constructed from the results obtained with the classical linearized model, and explicitly including the design variables of the collector, were proposed. These reduced models were then evaluated in terms of Parsimony, Exactness, Precision and Specialisation (PEPS). It was concluded that one of them (D2), using a low number of variables and of equations, is well suited for the design of solar air collector coupled with other sub-systems in more complex devices such as solar kiln with energy storag

Solar timber kilns: State of the art and foreseeable developments

Analysis of the evolution in solar heated drying kilns in recent decades shows that there have been a series of modifications to optimize their thermal and drying efficiency. Using an analysis method based on product design, we report on existing solar timber kilns. The dryers and their component units are studied, developments are noted, focusing on changing trends in technological systems. As a result of this analysis we suggest some future adaptations

L'évolution de la filière du palmier en Indonésie. I. La croissance du secteur (1848-1996)

Le développement de la culture du palmier à huile en Indonésie s'est fait très progressivement de 1848 à 1967, pour s'accélérer ensuite brutalement sous l'effet de la décision délibérée du gouvernement de substituer l'huile de palme à l'huile de coco dans le régime alimentaire de la population. La superficie plantée atteint actuellement près de 3 millions d'hectares, dont 50 % de plantations privées, 33 % de plantations villageoises et 17 % de plantations d'état. Parallèlement à la croissance de la production, la consommation d'huile de table issue de l'huile de palme a augmenté jusqu'à atteindre 11 kg par habitant, le marché intérieur absorbant de ce fait 60 % de la production d'huile brute. Sur le marché international, la part de l'Indonésie a doublé en 10 ans et représente actuellement 18 % des exportations mondiales. L'Europe et l'Asie les deux premiers clients de l'Indonésie à égalité, sont globalement destinataires de près de 90 % des exportations de 1997. (Résumé d'auteur

Chromosome 21 Scan in Down Syndrome Reveals DSCAM as a Predisposing Locus in Hirschsprung Disease

Jannot, Anne-Sophie et al.Hirschsprung disease (HSCR) genetics is a paradigm for the study and understanding of multigenic disorders. Association between Down syndrome and HSCR suggests that genetic factors that predispose to HSCR map to chromosome 21. To identify these additional factors, we performed a dose-dependent association study on chromosome 21 in Down syndrome patients with HSCR. Assessing 10,895 SNPs in 26 Caucasian cases and their parents led to identify two associated SNPs (rs2837770 and rs8134673) at chromosome-wide level. Those SNPs, which were located in intron 3 of the DSCAM gene within a 19 kb-linkage disequilibrium block region were in complete association and are consistent with DSCAM expression during enteric nervous system development. We replicated the association of HSCR with this region in an independent sample of 220 non-syndromic HSCR Caucasian patients and their parents. At last, we provide the functional rationale to the involvement of DSCAM by network analysis and assessment of SOX10 regulation. Our results reveal the involvement of DSCAM as a HSCR susceptibility locus, both in Down syndrome and HSCR isolated cases. This study further ascertains the chromosome-scan dose-dependent methodology used herein as a mean to map the genetic bases of other sub-phenotypes both in Down syndrome and other aneuploidies. © 2013 Jannot et al.This work was funded by the French National Research Agency (ANR, grants MRARE-HirGenet to SL, EvoDevoMut Grant, and ERare-HSCR Consortium to SL, IC, and SB), the Fondation pour la Recherche Médicale (FRM) to SL and JA; Fondation Jérôme Lejeune; the USA National Institutes of Health (R37 HD28088 to A.C.); the Italian Telethon (GGP04257 to IC); Fondo de Investigación Sanitaria. Instituto de Salud Carlos III (PI10/01290) and Consejería de Innovación, Ciencia y Empresa de la Junta de Andalucía (CTS-2590) to S.B.; the NWO (901-04-225) Bernoulle Foundation and Ubbo Emmius Foundation to R.M.W.H.Peer Reviewe

Analytical Calculation of Rotor Magnet Eddy-Current Losses for High Speed IPMSM

International audienceFor high-speed machines applications, eddy-current losses in the interior permanent magnet of synchronous machine (IPMSM) form a portion of the total losses which can be significant. Indeed, the magnets are exposed to the harmonic fields which rotate with respect to the rotor. The induced losses in the magnets provoke temperature arising that must be limited to avoid the risk of demagnetization. The study carries out a prediction of eddy current losses in PM where the skin effect is considered. A complete analytical model is presented and compared to 3D Finite Element (FE) harmonic computations. The results given by the proposed model are in agreement with the FEA results for local electromagnetic quantities and loss calculations. This approach can be useful for losses estimation in magnets when designing machines by analytical method