scholarly journals Development of High Performance BWR Fuel Bundle. Thermal-hydraulic Performance of CYCLONE Spacer.

1996 ◽  
Vol 38 (9) ◽  
pp. 771-775 ◽  
Author(s):  
Shinichi MOROOKA ◽  
Kenetsu SHIRAKAWA ◽  
Yasushi YAMAMOTO ◽  
Takashi YANO ◽  
Jiro KIMURA ◽  
...  
Keyword(s):  
High Performance ◽  
Hydraulic Performance ◽  
Fuel Bundle

ACR-1000™ Fuel Design Verification

2010 ◽  
Author(s):  
David J. Wren ◽  
Patrick Reid ◽  
Len L. Wright
Keyword(s):  
High Performance ◽  
Reactor Core ◽  
Cold Test ◽  
Performance Criteria ◽  
Extensive Experience ◽  
Fuel Bundle ◽  
Test Loop ◽  
Fuel Design ◽  
And Performance ◽  
The Impact

The ACR-1000™ design is an evolutionary advancement of the proven CANDU® reactor design that delivers enhanced economic performance, safety, operability and maintainability. The fuel for the ACR-1000 design is based on the well established CANDU fuel bundle design that has over 40 years of demonstrated high performance. Building on its extensive experience in fuel design and analysis, and fuel testing, AECL has designed a CANFLEX-ACR™ fuel bundle that incorporates the latest improvements in CANDU fuel bundle design. The ACR-1000 fuel bundle also includes features that enable the ACR-1000 to achieve higher fuel burn-up and improved reactor core physics characteristics. To verify that the CANFLEX-ACR fuel bundle design will meet and exceed all design requirements, an extensive program of design analysis and testing is being carried out. This program rigorously evaluates the ability of the fuel design to meet all design and performance criteria and particularly those related to fuel failure limits. The design analyses address all of the phenomena that affect the fuel during its residence in the reactor core. Analysis is performed using a suite of computer codes that are used to evaluate the temperatures, deformations, stresses and strains experienced by the fuel bundle during its residence in the reactor core. These analyses take into account the impact of fuel power history and core residence time. Complementing the analyses, testing is performed to demonstrate the compatibility of the fuel with the reactor heat transport system and fuel handling systems, and to demonstrate the ability of the fuel to withstand the mechanical forces that it will experience during its residence in the core. The testing program includes direct measurement of prototype fuel element and fuel bundle properties and performance limits. A number of different test facilities are used including a cold test loop and a hot test loop with a full-scale ACR-1000 fuel channel that operates at reactor coolant temperatures, pressures and flows. This paper summarizes the out-reactor test program and related analysis that provide the basis for verifying that the ACR-1000 fuel design meets its requirements.

Recent Development of Micro Ceramic Reactors for Advanced Ceramic Reactor System

2008 ◽  
Author(s):  
Toshio Suzuki ◽  
Toshiaki Yamaguchi ◽  
Yoshinobu Fujishiro ◽  
Masanobu Awano ◽  
Yoshihiro Funahashi
Keyword(s):  
High Performance ◽  
Fabrication Technology ◽  
Power Sources ◽  
Power Generators ◽  
Advanced Ceramic ◽  
Portable Power ◽  
Fuel Bundle ◽  
Micro Reactors ◽  
Ceria Electrolyte ◽  
Ceramic Reactors

Ceramic reactors, which convert materials and energy electrochemically, are expected to solve various environmental problems, and use of micro reactor design was shown to realize high performance reactor with high thermal durability operable at lower temperatures. Our research project “Advanced Ceramic Reactor” supported by NEDO targets to develop new fabrication technology for such micro reactors and modules using conventional, commercially available materials. In this study, fabrication technology of micro tubular ceramic reactors have been investigated for aiming solid oxide fuel cells (SOFCs) application, such as small distributed power generators, APU for vehicles, and portable power sources. So far, micro tubular SOFCs under 1 mm diam. using doped ceria electrolyte and Ni-ceria based cermet for tubular support has been successfully developed and evaluated. The single micro tubular SOFC showed cell performance of 0.46 W/cm2 (@0.7 V) at 550 °C with H2 fuel. Bundle design for such tubular cell was also proposed and fabricated. Discussion will cover fabrication technology of single tubular SOFC and bundle, and optimization of the cell and bundle design by considering gas pressure loss and current collecting loss.

Investigations On Flow And Flow-Induced Vibration Of Candu Fuel Bundles

2021 ◽  
Author(s):  
Alokendu Bhattacharya
Keyword(s):  
High Performance ◽  
Nuclear Reactor ◽  
Angular Position ◽  
Three Dimensional ◽  
Power Spectra ◽  
Wide Band ◽  
Major Step ◽  
Processing Scheme ◽  
Fuel Channel ◽  
Fuel Bundle

Excitations induced by three-dimensional unsteady flows of ordinary water coolant through a string of CANDU fuel bundles in a fuel channel are investigated in this thesis. Several comprehensive computational fluid dynamics (CFD) models are developed and solved by means of large eddy simulation (LES), high performance computers and parallel processing scheme. The 12-bundle flow model is the first ever developed concerning flow in a very complex CANDU fuel channel. The lateral fluid flow and flow-induced excitations on every fuel bundle are obtained and analyzed for various combinations of bundle angular positions. The coherent nature of the flow through the multiple bundles inside the fuel channel exhibiting fluid excitations of frequencies spreaded over a wide band in the power spectra is a source of bundle lateral vibration. The flow features of different bundle regime are correlated both in time and frequency domain and they are sensitive to the bundle-to-bundle angular position. This finding directs that, to study the flow and flow-induced excitations and vibrations of a bundle string, it is necessary to include all bundles for fluid-structure interactions. Results from the computational model reveal that the misaligned interface changes the flow pattern in the fuel channel. The mean lateral fluid forces increase by an order of magnitude and their RMS values raise about 3 to 4 times at some configurations compared to fully aligned situation. Experiments are also performed using the simulated CANDU bundles in an out-reactor setup to verify the computational results. An analysis of a complete fuel channel of a nuclear reactor using LES is at the forefront of current research worldwide and this study is a major step forward towards understanding and unfolding the fuel bundle vibration phenomenon.

scholarly journals Investigations On Flow And Flow-Induced Vibration Of Candu Fuel Bundles

2021 ◽  
Author(s):  
Alokendu Bhattacharya
Keyword(s):  
High Performance ◽  
Nuclear Reactor ◽  
Angular Position ◽  
Three Dimensional ◽  
Power Spectra ◽  
Wide Band ◽  
Major Step ◽  
Processing Scheme ◽  
Fuel Channel ◽  
Fuel Bundle

Excitations induced by three-dimensional unsteady flows of ordinary water coolant through a string of CANDU fuel bundles in a fuel channel are investigated in this thesis. Several comprehensive computational fluid dynamics (CFD) models are developed and solved by means of large eddy simulation (LES), high performance computers and parallel processing scheme. The 12-bundle flow model is the first ever developed concerning flow in a very complex CANDU fuel channel. The lateral fluid flow and flow-induced excitations on every fuel bundle are obtained and analyzed for various combinations of bundle angular positions. The coherent nature of the flow through the multiple bundles inside the fuel channel exhibiting fluid excitations of frequencies spreaded over a wide band in the power spectra is a source of bundle lateral vibration. The flow features of different bundle regime are correlated both in time and frequency domain and they are sensitive to the bundle-to-bundle angular position. This finding directs that, to study the flow and flow-induced excitations and vibrations of a bundle string, it is necessary to include all bundles for fluid-structure interactions. Results from the computational model reveal that the misaligned interface changes the flow pattern in the fuel channel. The mean lateral fluid forces increase by an order of magnitude and their RMS values raise about 3 to 4 times at some configurations compared to fully aligned situation. Experiments are also performed using the simulated CANDU bundles in an out-reactor setup to verify the computational results. An analysis of a complete fuel channel of a nuclear reactor using LES is at the forefront of current research worldwide and this study is a major step forward towards understanding and unfolding the fuel bundle vibration phenomenon.

Further Details of a Numerical Analysis on the Thermal Hydraulic Effect of Wrapped Wire Spacers in Fuel Bundle

2020 ◽  
Vol 6 (3) ◽  
Author(s):  
Attila Kiss ◽  
Bence Mervay
Keyword(s):  
Heat Transfer ◽  
Fuel Assembly ◽  
High Performance ◽  
Transverse Velocity ◽  
Axial Direction ◽  
Optimal Choice ◽  
Strong Mixing ◽  
Fuel Rods ◽  
Ongoing Research ◽  
Fuel Bundle

Abstract The application of relatively simple and cheap wrapped wire spacer in the European supercritical water-cooled reactor (SCWR) (high-performance light water reactor (HPLWR)) has been proposed in order to provide enhanced heat transfer in the fuel assembly without unacceptable penalty in pressure loss. The wires cause twisting flow in the fuel assembly, which means the coolant not only flows straight in the axial direction but also has a significant transverse velocity component, and strong mixing between neighboring subchannels occurs. The aim of this ongoing research is to numerically investigate the effect of wrapped wire spacers on thermal hydraulics of the turbulent coolant flow and its heat transfer in a small bundle of four fuel rods. One bare and six-wired geometries with varying wire pitches (1–6 turn(s) of wires) have been studied. It was found that the wires generate significant amount of transverse velocity, decrease the wall temperature, and increase the heat transfer coefficient mostly in corner subchannels which were the hottest in bare geometry. Thus, the presence of wires enhances heat transfer where it is most needed. Temperature hot spots with moderate values have been identified on the cladding wall of fuel rods. Based on the results, a technically optimal choice of number of wire turns from thermal hydraulic sense has been proposed.

A High Performance Energy Analyzer for Use in Electron Scanning Microscopy

1969 ◽  
Vol 27 ◽  
pp. 14-15
Author(s):  
A. V. Crewe ◽  
M. Isaacson ◽  
D. Johnson
Keyword(s):  
High Performance ◽  
Vertical Plane ◽  
Median Plane ◽  
Electron Gun ◽  
Uniform Field ◽  
Loss Mechanism ◽  
Electron Scanning Microscopy ◽  
Sector Type ◽  
Double Focusing ◽  
Electron Energy Loss

A double focusing magnetic spectrometer has been constructed for use with a field emission electron gun scanning microscope in order to study the electron energy loss mechanism in thin specimens. It is of the uniform field sector type with curved pole pieces. The shape of the pole pieces is determined by requiring that all particles be focused to a point at the image slit (point 1). The resultant shape gives perfect focusing in the median plane (Fig. 1) and first order focusing in the vertical plane (Fig. 2).

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

Use of the Magnetostatic Analogue In Electromagnetic Lens Engineering

1970 ◽  
Vol 28 ◽  
pp. 360-361
Author(s):  
John W. Coleman
Keyword(s):  
Boundary Conditions ◽  
High Performance ◽  
Force Fields ◽  
Optical Design ◽  
Direct Conversion ◽  
Design Engineering ◽  
Design Data ◽  
Scalar Potentials ◽  
Geometric Elements ◽  
At Will

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.

Prospects for convergent beam electron diffraction with a 200kV cold field-emission transmission electron microscope

1991 ◽  
Vol 49 ◽  
pp. 466-467
Author(s):  
J W Steeds ◽  
R Vincent
Keyword(s):  
Field Emission ◽  
High Performance ◽  
Small Diameter ◽  
Convergent Beam Electron Diffraction ◽  
Zone Axis ◽  
Medium Voltage ◽  
Transmission Electron ◽  
Good Crystallinity ◽  
Special Modification ◽  
Convergent Beam

We review the analytical powers which will become more widely available as medium voltage (200-300kV) TEMs with facilities for CBED on a nanometre scale come onto the market. Of course, high performance cold field emission STEMs have now been in operation for about twenty years, but it is only in relatively few laboratories that special modification has permitted the performance of CBED experiments. Most notable amongst these pioneering projects is the work in Arizona by Cowley and Spence and, more recently, that in Cambridge by Rodenburg and McMullan.There are a large number of potential advantages of a high intensity, small diameter, focussed probe. We discuss first the advantages for probes larger than the projected unit cell of the crystal under investigation. In this situation we are able to perform CBED on local regions of good crystallinity. Zone axis patterns often contain information which is very sensitive to thickness changes as small as 5nm. In conventional CBED, with a lOnm source, it is very likely that the information will be degraded by thickness averaging within the illuminated area.

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