[en] The vibrations induced in tube array by a transversal flow are of great practical interest because of their destruction effects especially on heat exchanger. Through turbulence can significantly excite the tube by itself, most intense vibrations are still caused by fluidelastic phenomena. The study described in this paper gives important information concerning the characteristics of these phenomena. A lot of bundlle mock-ups with various pitches have been tested in air. Large range parameter domains have been investigated (flow velocities, velocity profiles, natural frequencies and damping ratios of tubes, etc ...)

[en] We develop a velocity-dependent one-scale model for the evolution of domain wall networks in flat expanding or collapsing homogeneous and isotropic universes with an arbitrary number of spatial dimensions, finding the corresponding scaling laws in frictionless and friction dominated regimes. We also determine the allowed range of values of the curvature parameter and the expansion exponent for which a linear scaling solution is possible in the frictionless regime.

[en] Korea Atomic Energy Research Institute (KAERI) is conducting development on the pyrorpcess mock-up facility (PMF) for full-scale pyroprocess inactive demonstration. A conceptual design of the PMF was carried out and design study for PMF is being carried out in this year. The PMF will incorporate an integrated engineering scale pyroprocessing system for an advanced nuclear fuel cycle technology. The conceptual requirements of the process equipments had been studied to build the basic data such as equipments size, heat load, weight, operation conditions, feed materials and product materials. The PMF cell size, capacity requirements of utility service such as HVAC, remote handling equipments, safety issues had been considered in conceptual design stages, too. The PMF shall be comply with safety requirements such as process and structure safety, radioactivity levels and contamination control, radiation monitoring for personnel protection, and fire prevention

[en] This paper proposes a conclusive scalable model for the complete actuation response for ionic polymer metal composites (IPMC). This single model is proven to be able to accurately predict the free displacement/velocity and force actuation at varying displacements, with up to 3 V inputs. An accurate dynamic relationship between the force and displacement has been established which can be used to predict the complete actuation response of the IPMC transducer. The model is accurate at large displacements and can also predict the response when interacting with external mechanical systems and loads. This model equips engineers with a useful design tool which enables simple mechanical design, simulation and optimization when integrating IPMC actuators into an application. The response of the IPMC is modelled in three stages: (i) a nonlinear equivalent electrical circuit to predict the current drawn, (ii) an electromechanical coupling term and (iii) a segmented mechanical beam model which includes an electrically induced torque for the polymer. Model parameters are obtained using the dynamic time response and results are presented demonstrating the correspondence between the model and experimental results over a large operating range. This newly developed model is a large step forward, aiding in the progression of IPMCs towards wide acceptance as replacements to traditional actuators

[en] Based on the spatial factor other than the temporal accumulation, the hidden tree model was built up to model scale-free networks. This paper further assumed that a node has multiple roles in different hidden trees, and explored the multi-role hidden tree model. The experimental results showed that multi-role hidden tree model can also produce scale-free networks. This conclusion indicates that the hidden tree model is robust with multiple roles

[en] Highlights: • A multi-scale model of pipeline fittings is acquired considering high pressure pulsating fluid. • Influence of high pressure pulsating fluid on seal of pipeline fittings is acquired. • Sealing property of pipeline fittings is accuratly analyzed under certain pressure pulsating fluid. Based on the study of pressure pulsation fluid characterization, the present study investigates the impact generated by high-pressure pulsating fluid on pipeline fittings’ sealing characteristics. In the meanwhile, it analyzes the influence of the internal fluid pulsation amplitude and fluid pulsation at different pressures on pipeline fittings sealing characteristics. A comparative study on the research results demonstrate that due to the action characteristics of fluid pulsation, pipeline fittings sealing characteristics change periodically in pulsation period, and the change range of sealing contact area of pipeline fittings remains basically consistent with that of high stress area. Moreover, the sealing contact area and high stress area of pipeline fittings increase when fluid pulsation amplitude increases. By maintaining fluid pressure constant, the maximum sealing area of pipeline fittings is slightly larger than that of pipeline fittings under no pressure condition during the pulsating period. In addition, the area of high stress area changes significantly.

[en] We develop a velocity-dependent one-scale model describing p-brane dynamics in flat homogeneous and isotropic backgrounds in a unified framework. We find the corresponding scaling laws in frictionless and friction-dominated regimes considering both expanding and collapsing phases.

[en] In this paper, we described the development of two evaluation systems for enhancing remote operability and maintainability of pyro processing equipment for use in the PRIDE? a digital mock-up and a remote handling evaluation mock-up is a virtual facility of the PRIDE. This mock-up consists of the geometry that allows the pyro processing equipment to be installed, the apparatuses by which the pyro processing equipment that perform specified tasks of each process. The digital mock-up will provide an efficient means for simulating and verifying the conceptual design, design developments, arrangements, and rehearsal of the pyro processing equipment from the remote operation and maintenance viewpoint in a virtual process environment in advance before the pyro processing equipment is constructed. A remote handling evaluation mock-up (RHEM) is a 1/8 scale-downed mock-up of the PRIDE in length only and has the same width and height as ones of the PRIDE which has a configuration of 40.3 Χ 4.8 Χ 6.4 (LxWxH) m. The RHEM is a useful means for verifying the remote operability and maintainability of various constructed pyro processing equipment in advance before they are installed in the PRIDE. Currently. both the digital mock-up and the RHEM are under use to advance the pyro processing equipment

[en] This report described the construction of digital mockup to need verification about remote process operation and maintenance at the nuclear fuel cycle facility that treats with spent fuel. Digital mockup composes deployment of virtual devices. This report described a scheme of design guidelines and method of device modeling for the increase of effective work in the process of this construction. Also, remote handling devices design a 3D modeling and full-scale digital mockup as same as real PRIDE facility is constructed. The construction of digital mockup about virtual PRIDE facility gets to base to verify the possibility of operation and maintenance. The process equipment will be designed in the future. Layout analysis through workspace, and accessibility and work ability of remote handling devices using this was examined

[en] In this study, to improve the measurement accuracy of coolant flow in a coolant flow simulator, elimination of external noise are enhanced by adding ground pattern in the control panel and earth around signal cables. In addition, a heating unit is added to strengthen the fluctuation signal by heating the coolant because the source of signals are heat energy. Experimental results using the improved system shows good agreement with the reference flow rate. The measurement error is reduced dramatically compared with the previous measurement accuracy and it will help to analyze the performance of nuclear fuels. For further works, out of pile test will be carried out by fabricating a test rig mockup and inspect the feasibility of the developed system. To verify the performance of a newly developed nuclear fuel, irradiation test needs to be carried out in the research reactor and measure the irradiation behavior such as fuel temperature, fission gas release, neutron dose, coolant temperature, and coolant flow rate. In particular, the heat generation rate of nuclear fuels can be measured indirectly by measuring temperature variation of coolant which passes by the fuel rod and its flow rate. However, it is very difficult to measure the flow rate of coolant at the fuel rod owing to the narrow gap between components of the test rig. In nuclear fields, noise analysis using thermocouples in the test rig has been applied to measure the flow velocity of coolant which circulates through the test loop