1,722,316 research outputs found
Analysis of a helical coil once-through molten salt steam generator: Experimental results and heat transfer evaluation
No full textA molten salt helical coil steam generator is an alternative to kettle- or drum-type evaporators which are currently used in commercial-scale solar thermal power plants. A 300 kW prototype was tested during the OPTS project at ENEA. The experimental results presented in this paper have been used to validate a detailed heat transfer analysis of the whole system. The heat transfer analysis deals with the study of both the overall heat transfer coefficient and the shell-side heat transfer coefficient. Due to the specific features of this type of system, no correlations were available in the literature. A new numerical model to predict the performance of large-scale systems is also presented. © 2016 Author(s)
Experimental tests about the cooling/freezing of the molten salts in the receiver tubes of a solar power plant with parabolic trough
No full textIn 2003 ENEA realized the PCS experimental Facility at Casaccia Research Centre (Rome, Italy), in order to test in real operating conditions the components of a parabolic trough solar plant, and to evaluate the technical feasibility of using the solar molten salts mixture (60% NaNO3, 40% KNO3, melting point 220÷240°C) in such a type of plant. ENEA also had the need to assess the behaviour of the solar receiver tubes during abnormal operating situations (wrong operation, pump block, power failure, etc.), when a block of the circulation of the molten salts may occur and cause the cooling or, worse, the freezing of the salts mixture inside the pipes. Some experimental tests have been performed, aimed to examine what happens in such a cases. In fact, without quick maneuvers to restart the circulation of the molten salts or to readily empty the receiver tubes, the molten salts contained in them may cool down to temperatures near/below the solidification. In this report are shown the results of the experimental tests carried out on the receiver tubes of the PCS Facility by cooling the process fluid down to temperatures near or below its freezing point. The tests show that the solidification of the salts does not damage the components of the plant but it is manageable and reversible, provided you apply the correct procedures. © 2017 Author(s)
Rescuing my time from science
No full textIt was a cold autumn day a couple years ago when I first felt that pursuing a Ph.D. was warping my sense of time. I had started working at 8: 30 in the morning. By 8 in the evening, when almost everybody else had left, I was still in my office. I had so much work still to do that I reluctantly called my life partner to tell her that I would not be home for dinner. As I finally headed home around midnight, walking down dark, empty corridors and through the deserted university square, I realized that I was living in a sort of time warp-which was particularly ironic given that I was studying how daily activities shape our sense of time. Now, though, after years of allowing my work to take over my life, I'm reclaiming my power to decide how to spend my time
Ossificazione della colonna vertebrale nel ratto in condizioni di sviluppo normali e alterate.
No full textApplication and internal validation of lung ultrasound score in COVID-19 setting: The ECOVITA observational study. Authors’ reply
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