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[en] Combustion Engineering, Rolls Royce and Associates, and the UKAEA have found that, independently, their thinking on the future of light water reactors has been leading towards reconsideration of small units -around 300 MWe. A study group has been set up to collaborate on the SIR (Safe Integral Reactor). The integral reactor has its major primary circuit components, core, steam generators and reactor coolant pumps built into a single large reactor vessel. This turns out to provide many advantages over the usual dispersed or loop plant. (author)
[en] An introductory overview is given of the history, the status and future trends of storage rings with beam cooling. Achievements obtained with cooling rings are outlined, the main cooling methods operational in circular machines are recalled and some features of the 'ion coolers' now under construction or planned are briefly discussed. It is concluded that the combination of the storage and beam cooling techniques will continue to lead to new discoveries and surprises. (orig.)
[en] This paper presents a GPC-PID control strategy for a cooling-coil unit in heating, ventilation and air conditioning systems. By analysis of the cooling towers and chillers, different models in the occupied period are considered in each operating condition. Because of the complication of components, well tuned PID controllers are unsatisfied, and the results are poor over a wide range of operation conditions. To solve this problem, a GPC-PID controller with hierarchical structure is proposed based on minimizing the generalized predictive control criterion to tune conventional PID controller parameters. Simulation and experiments show that the proposed controller is able to deal with a wide range of operating conditions and to achieve better performance than conventional methods
[en] Highlights: ► Demonstrate solar energy misting system for the first time to our knowledge. ► Return on investment for such a system is recovered within two and half years. ► Solar panel tilt position is 25° due south in Medina Munawarah. ► The misting system is capable of lowering ambient temperature over 10 °C. - Abstract: We demonstrated for the first time to our knowledge a misting system that is powered by solar energy. The system was used to cool down an open area in Medina, Saudi Arabia. The ambient and surrounding temperatures were measured and compared for different timing signals that were applied to the misting system. The used solar panel performance is evaluated for different loads, and tilting settings. The return on investment for the misting system is found to be about two years and half.
[en] New results on laser cooling of stored, bunched, relativistic ion beams are presented. For the first time it has been possible to cool an ion beam with large momentum spread without initial electron cooling or scanning of the bunching frequency by using a single cw laser system
[en] A coolant pump for a liquid metal cooled nuclear reactor construction is described which has its impellor hub mounted on the drive shaft with an annular clearance. A drive coupling is effected by a plurality of cylindrical keys disposed parallel to the longitudinal axes of the hub and shaft and equally spaced in the clearance between them. (author)
[en] Highlights: • The passive containment cooling system (PCCS) model for the AP600 has been developed and validated. • The performance for different cooling systems is compared in two AP600 hypothetical scenarios. • The detailed analyses of the interaction between spray system and external PCCS are explored. • The superiority of the combined cooling system is explained. - Abstract: The process of heat removal and depressurization is one of the most significant issues in nuclear safety design. The spray system and the passive containment cooling system (PCCS) are two essential safety arrangements to protect the integrity of the containment and the apparatus. In the present study, the performance of the combined cooling system is investigated by using three-dimensional CFD simulations. The interactions between spray system and external PCCS are analyzed. The numerical results reveal that neither the single passive containment cooling nor the spray system can remove heat and depressurize the containment efficiently under all circumstances. Whereas the combined passive and spray cooling system proposed in this paper can overcome the insufficiency and take the advantages of both the two systems. The mechanism for the superiority of the combined system is explained through the droplets phase change, vapor transportation, wall condensation and film cooling heat transfer processes.
[en] The present study provides the overview of Maisotsenko Cycle (M-Cycle) applications for gas cooling in compressor systems. Various schemes of gas cooling systems are considered regarding to their thermal efficiency and cooling capacity. Preliminary calculation of M-cycle HMX has been conducted. It is found that M-cycle HMX scheme allows to brake the limit of the ambient wet bulb temperature for evaporative cooling. It has demonstrated that a compact integrated heat and moisture exchange process can cool product fluid to the level below the ambient wet bulb temperature, even to the level of dew point temperature of the incoming air with substantially lower water and energy consumption requirements. (paper)