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[en] A heater tank is designed and developed at the Malaysian Nuclear Agency whereby the setup allows investigation of the heat transfer between heater rods and fluids in a tank. The heater tank is a physical simulation of an array of nuclear fuel rods within a nuclear fuel assembly. In this paper, we introduce the tank, heating rod, and electrical control, with a focus on design. The heater tank shall be used as an educational unit to study convective cooling and for tomographic inspection. (author)
[en] RTP cooling system was designed to provide sufficient cooling to the reactor core. Heat generated in the reactor core were carried by the primary cooling system to the secondary cooling system through the heat exchangers as a transfer medium. The performance of primary and secondary cooling system in different operation condition; start-up, steady state and shutdown were characterized and evaluated. The characterization of operational parameter has been done at nominal power level in normal operation. The aims of this study are to evaluate the response of the primary and secondary cooling system in start-up, steady state and shutdown condition and to determine the nominal range of parameters at each operating condition. (author)
[en] Safety Design Guidelines Development: Fundamental safety principles and common safety goals for all Gen-IV systems. A set of criteria reflecting GIF safety approach to achieve harmonized safety requirements of SFR system. A set of guidelines on how to implement the design criteria and address SFR-specific safety topics. Domestic regulations for design of reactor core, cooling system, and other structures, systems, and components.
[en] In this study, a solar ejector cooling system is theoretically analyzed to evaluate refrigerants and determine their performance characteristics and environment-friendly nature for a fixed ejector geometry under a set of standard operating conditions. The results show that the refrigerant R1234yf is the best choice for the cycle, and is an environment-friendly refrigerant with thermo-physical properties similar to that of R134a. Moreover, it has a high entrainment ratio and is cheap when compared to other refrigerants, nonflammable, and safe. The results indicate that the cooling cycle COP increases during the day hours as the generator temperature increases and reaches a maximum value of 0.59 at an optimum generator temperature of 86 C in the middle of the day. The overall efficiency of the system varied in the range 38–45%. Furthermore, it was found that increasing the generator pressure by 40% reduced the COP by 58.5% and increased the critical backpressure by 27.3%.
[en] Loop heat pipe (LHP) is an effective two-phase heat transfer device that utilizes evaporation and condensation of a working fluid. LHP is widely used in a passive cooling system, highly reliable and a very high thermal conductive device. However, extreme power density can cause dry-out in the evaporator section of LHP and might hinder the performance of the cooling system. The purpose of this research is to design and manufacture a new prototype of LHP by modifying the conventional LHP. The modification was performed by adding a diaphragm pump, called hybrid loop heat pipe (HLHP). The experimental results show that the installation of pumps in the modified LHP was able to prevent the occurrence of a dry out and reduce the operating temperature. Under a constant conductance mode, the pump was activated for 20 minutes and succeded in forcing the system to a new stable condition with a significant temperature drop. These results indicate that HLHP is very promising as a two-phase cooling system that can be proposed for devices that produce high heat flux.
[en] In this paper, a model of irreversible three-electron-reservoir energy selective electron (ESE) cooling device with heat leakage is established. By utilizing the finite time thermodynamics, the optimal performance of the cooling device is studied and the influences of chemical potential differences of electron reservoirs, center energy level of energy filters and heat leakage on the optimal performances are discussed. On the basis of cooling rate and coefficient of performance (COP) analyses, the exergy-based ecological function and figure of merit are proposed as objective functions. The operation properties of ESE cooling device with different objective functions are investigated and the optimal performance region is obtained. Higher cooling rate and COP can both be attained for the ESE cooling device when it is working in the optimal performance region.
[en] One way to increase efficiency of the electron cooling is to increase the electron density in the reference frame of an electron beam. In most cases, the higher energy of ion beams the less its size, so one can reduce the diameter of the electron beam preserving the total current and increasing the current density. This paper discusses two electron gun designs for high-voltage electron cooling systems: the electron gun with at cathode and the gun with convex one. Each gun is able to produce an electron beam with diameter up to 1 cm and current about 1 A.
[ru]Одним из способов повышения эффективности электронного охлаждения является повышение плотности электронов в системе отсчета пучка. Как правило, с увеличением энергии охлаждаемого пучка ионов уменьшают его размер, следовательно, можно увеличить плотность электронного тока, уменьшив диаметр пучка электронов и сохранив его полный ток. В работе описаны два варианта электронной пушки для высоковольтных систем электронного охлаждения с плоским и выпуклым катодами, в каждом из которых электронная пушка способна произвести пучок диаметром до 1 см и с током порядка 1 А.
[en] The RSG-GAS cooling system consists of primary and secondary cooling systems. The primary cooling system functions to take heat from the reactor core while the secondary cooling system serves to take heat from the primary cooling system through a heat exchanger and release it to the environment. The reactor coolant system has been operating for more than 28 years so it needs revitalization. One part that is replaced is the cooling tower. The reactor coolant system capability after revitalization can be seen through the comparison of secondary and primary cooling system calorimetry power and comparing the Tinlet and Toutlet reactor coolant systems with their design values. From the results of the comparison, the change in calorimetry power on the primary side is proportional to the change in the secondary side calorimetry power. This shows the heat transfer from the primary to the secondary cooling system and the process of releasing heat to the environment goes well. For a comparison of the reactor coolant Tinlet-Outline at full power of 30 MW, the Tinlet-Outflow of primary and secondary cooling systems does not exceed the maximum design limit value. From all comparisons showing a new cooling tower the secondary cooling system provides a better level of heat dissipation when the reactor operates. (author)