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Novel thermochemical energy storage systems that employ fluidized beds of CaO/Ca(OH) 2 for hydration/dehydration reactions are under development because of the inherent advantages of the low cost of the materials and their relatively high temperature operation windows (450ºC-550ºC). We report in this work the results of the first steady state experiments conducted in a new pilot plant designed to test the concept under realistic reactor conditions. The pilot has a fluidized bed reactor with an internal diameter of 0.108 m and a height of 780 mm fed continuously with gas and solids as well as heat exchangers to supply/extract the required reaction heat. The experimental results during dynamic and steady state periods were fitted to a KL reactor bubbling bed model, using kinetic parameters from thermogravimetric studies and a single crossflow factor. The resulting continuous reactor model will serve as useful tool for the continued scaling up of this technology.

This paper reports on the performances and the optimization of a 40 mm diameter water flow energy harvester based on an axial turbine (horizontal axis propeller) coupled to a customized permanent magnet generator. To the best of our knowledge, this work is one of the first comprehensive studies in the low dimensional and flow velocities ranges. The parameters of the propeller have been empirically optimized ( D l =1, B=4 blades) by the means of experiments in a test-bench pipe at various flow rates from 1 to 9 m 3 h −1 . The best propeller design has been selected for its performances in terms of electrical power and pressure drop. A customized permanent magnet converter with ferromagnetic elements has been modeled, optimized with finite elements simulations and fabricated.

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This paper describes an experimental study on the convective heat transfer of SiO2/water nanofluids inside a circular tube with imposed wall temperature. To our knowledge, very few papers have been published with temperature boundary conditions and none in cooling conditions. The experimental apparatus is described which allows us to measure local wall temperatures as well as fluid inlet/outlet temperatures. The flow regimes range from laminar to turbulent. The Reynolds and Nusselt numbers are deduced by using thermal conductivity and viscosity values measured with the same temperature conditions as those in the tests. The shear rate influence is also taken into account in the viscosity determination. The results indicate that the general trend of standard correlations is respected. However, the heat transfer coefficient values are higher than observed with pure water. An explanation is proposed.

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