Pulsed eddy current (PEC) technique generates responses over a wide range of frequencies, containing more spectral coverage than traditional eddy current *** current pulsed thermography (ECPT), a newly developed non-d...
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Pulsed eddy current (PEC) technique generates responses over a wide range of frequencies, containing more spectral coverage than traditional eddy current *** current pulsed thermography (ECPT), a newly developed non-destructive testing (NDT) technique, has advantages such as rapid inspection of a large area within a short time, high spatial resolution, high sensitivity and stand-off measurement *** paper investigates ECPT for the evaluation of gear fatigue *** paper proposes a statistical method based on single channet blind source separation to extract details ot gear *** discussion of transient thermal distribution and patterns of fatigue contact surfaces as well as the non-contact surfaces have been *** addition, the measurement for gears with different cycles of fatigue tests by ECPTand the comparison results between ECPT with magnetic Barkhausen noise (MBN) have been *** comparison shows the competitive capability of ECPT in fatigue *** open access database of ECPT for gear fatigue evaluation is provided, and freely obtained to further analysis for gear fatigue evaluation.
Recent studies on stress corrosion cracking properties of 321 bend pipe and pipe with weld, 316NG austenitic stainless steel pipe in ocean environment in virtue of slow strain rate tensile stress corrosion crack test ...
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Recent studies on stress corrosion cracking properties of 321 bend pipe and pipe with weld, 316NG austenitic stainless steel pipe in ocean environment in virtue of slow strain rate tensile stress corrosion crack test are performed in different concentration of NaCl solution. Elongation and max tensile stress are selected as parameters to evaluate the SCC susceptibility based on the phenomenon that elongation and max stress fall as samples being exposed to NaCl solution environment, the results show that 316NG has the best stress corrosion crack resistance and 321 bend pipe materials behavior oppositely. In addition, the influence of differing strain rate and concentration of NaCl solution on properties of materials are researched, elongation increases along with tensile strain rate enhancement, mechanical properties are immune to variety of Cl- concentration from 3.5% to 26.5%.
On the basis of establishing 3D modeling of gear form grinding machine, all levels of subassemblies of the grinding machine were assembled. Then the virtual assembly of total grinding machine was completed. Based on t...
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Introduce the basic concept of best rational approximation and constructing procedure of the best rational approximation function in Laplace domain. By an illustrative example the design method of FOC based on best ra...
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Introduce the basic concept of best rational approximation and constructing procedure of the best rational approximation function in Laplace domain. By an illustrative example the design method of FOC based on best rational approximation is discussed. The performance comparison of transfer functions between the FOC obtained by best rational approximation method and conventional PID shows that it is effective to apply the method in design of FOC, which can guarantee maximum absolute error of amplitude frequency characteristic of approximation function in a given error tolerance.
During an overpower transient, the fuel rod cladding may be subjected to major stresses due to differential expansion of the fuel and the cladding. This may lead to clad failure through the Pellet Clad Interaction (PC...
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During an overpower transient, the fuel rod cladding may be subjected to major stresses due to differential expansion of the fuel and the cladding. This may lead to clad failure through the Pellet Clad Interaction (PCI) phenomenon. So the aim of this paper is to present the linear power reached during the most limiting condition II transients(Excessive Load Increase (ELI), Uncontrolled RCCA Withdrawal at Power (URWP) and undetected Rod Drop (RD)) with respect to Qinshan-II long cycle fuel management project PCI analysis.
Hydrogen combustion in the containment building may be a threat to containment *** in some subcompartments,hydrogen detonation is more easier to happen,which may destroy the containment structure or the safety equipme...
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Hydrogen combustion in the containment building may be a threat to containment *** in some subcompartments,hydrogen detonation is more easier to happen,which may destroy the containment structure or the safety equipments in the containment. A study has been carried out using the GASFLOW three-dimensional CFD code to evaluate the hydrogen distribution in the subcompartment during a severe *** Chinese 600MW NPP containment is modeling by GASFLOW. The GASFLOW calculation gave detailed results for the spatial distribution of gas concentrations in the reactor coolant pump（RCP） compartment and the steam generator（SG） compartment within containment.
The advanced pressurized water reactor with a tight hexagonal lattice has its potential to improve uranium utilization. With a smaller pitch-to-diameter ratio(p/d) ranging from 1.06 to 1.20, a major problem is the eme...
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The advanced pressurized water reactor with a tight hexagonal lattice has its potential to improve uranium utilization. With a smaller pitch-to-diameter ratio(p/d) ranging from 1.06 to 1.20, a major problem is the emergency core cooling in a loss-of-coolant accident. The NEPTUN-III and FLORESTAN flooding experiments at PSI and KfK have been performed during the verification period 1985-1990, and the results shows that the reflooding behavior of LWHCR is quite different from that of LWR with higher peak clad temperatures and smaller quench rates. The existing system codes like RELAP5, CATHARE, TRAC may not be able to be used in the calculations of the reflooding phase of LWHCR. Though some efforts have been put into the validation of the improvement of codes, the results are not so good. In this study, the characteristics of the reflooding behavior of tight lattice are pointed out, and the deficiencies of the reflooding models of RELAP5/MOD3 are also fount out after a simulation of the NEPTUN-III reflooding test. The precursory cooling in tight lattice is not effective especially at low reflooding rates (<4cm/s), the droplet enhancement is not significant compared to LWR, and the vapor Reynolds number is much smaller. Finally, a few modifications to RELAP5/MOD3 are made. Compared with the original code, the modified one can better predict the reflooding phase of tight lattice especially the peak clad temperatures at low reflooding rates. More work should be done to deal with the heat transfer characteristics in the transition region of reflooding in tight lattice..
This paper describes a calculation model for pre-stressed bolted joints used to connect turntable bearing to the flanges. A traditional pre-stressed bolted joint calculation model is described and its insufficiencies ...
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Based on BPR theory, the new product development and manufacturing process status of a discrete manufacturing enterprise was analysed with finding out its existing problems, then a new reasonable process was designed ...
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Without considering the echo signal power changes caused by target distance changes during the accumulated time the traditional radar equation is hardly applied. We take account of the effects of velocity, signal-to-n...
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