Tanaka, Masaaki; Miyake, Yasuhiro*
Nippon Kikai Gakkai M&M 2015 Zairyo Rikigaku Kanfarensu Koen Rombunshu (Internet), 3 Pages, 2015/11
A prototype coupling method consisting of the fluid-structure thermal interaction simulation code MUGTHES and the structural thermal stress analysis code FINAS with interface program MUFIN has been developed in order to estimate the thermal fatigue in the SFRs. As a fundamental validation of the coupled method, it was applied to the water experiment for thermal mixing phenomena in a T-junction piping system. In the experiment, thermal interaction between the fluid and the structure made of aluminum installed to the branch pipe side wall was considered. Through the numerical simulations, applicability of the coupled method was confirmed.
Tanaka, Masaaki; Miyake, Yasuhiro*; Karakida, Yasuhisa*
Proceedings of 2nd International Conference on Maintenance Science and Technology (ICMST-Kobe 2014), p.79 - 80, 2014/11
A coupled method of fluid-structure thermal interaction simulation and thermal stress analysis has been developed through the interface program to carry out direct numerical estimation of the thermal fatigue. The prototype method was applied to the thermal mixing phenomena in T-junction Piping System.
Kasahara, Naoto; Yacumpai, A.*; Takasho, Hideki*
JNC-TN9400 99-019, 34 Pages, 1999/02
At incomplete mixing area of high temperature and low temperature fluids near the surface of structures, temperature fluctuation of fluid gives thermal fatigue damage to wall structures. This thermohydraulic and thermomechanical coupled phenomenon is called thermal striping, which has so complex mechanism and sometimes causes crack initiation on the structural surfaces that rational evaluation methods are required for screening rules in design codes. In this study, frequency response characteristics of structures and its mechanism were investigated by both numerical and theoretical methods. Based on above investigation, a structural response diagram was derived, which can predict stress amplitude of structures from temperature amplitude and frequency of fluids. Furthermore, this diagram was generalized to be the Non-dimensional structural response diagram by introducing non-dimensional parameters such as Biot number, non-dimensional frequency, and non-dimensional stress. The use of the Non-dimensional structural response diagram appears to evaluate thermal stress caused by thermal striping, rapidly without structural analysis, and rationally with considering attenuation by non-stationary heat transfer and thermal unloading. This diagram can also give such useful information as sensitive frequency range to adjust coupled thermohydraulic and thermomechanical analysis models taking account of four kinds of attenuation factors: turbulent mixing, molecular diffusion, non-stationaly heat transfer, and thermal unloading.
; Tanai, Kenji; Taniguchi, Wataru; Sakai, Yuichi*
PNC-TN8410 95-027, 56 Pages, 1995/02
Bains, R.S.*; Sugimoto, Jun
JAERI-Research 94-007, 66 Pages, 1994/08
no abstracts in English
PNC-TN9410 90-096, 162 Pages, 1990/06
Thermal transient strength tests in using the Thermal Transient Strength Test Facility for Structures (TTS) have been carried out to develop the design method for fast breeder reactor components under thermal loadings. The design and the fabrication of the Welded Vessel Model which is to be tested at TTS are described in this report. In this model, the noteworthy typical shape and stress distribution as seen in the structural design of Large Fast Breeder Reactor (LFBR) and the modified SUS316 which is a hopeful material for LFBR are incorporated. The Welded vessel Model is a cocoon-like model which has 25mm thickness, 2210mm hight and 850mm inner diameter, and it has seven test portions of interest, namely inlet/outlet nozzle, upper/skirt Y-janctions, vessel ring, inner shell ring and inner shell support flange. In design of this model, thermal transient conditions were established by performing Hydraulic-thermal analyses, and then, heat transfer analyses and thermal stress analyses were performed. Test portions of interest were evaluated using the special design guide for TTS tests. Materials and welding method adopted are basically the ones applicable to LFBR's reactor structures.
PNC-TN9410 90-054, 125 Pages, 1990/01
A preliminary analysis was performed on the sodium thermal fatigue tests which are planned to be conducted with the "Sodium Thermal Fatigue Test Apparatus", which was recently constructed in the material development section. This test machine was constructed for the purpose of aquisition of data needed for sofistication of the evaluation method of creep-fatigue and crack propagation of welded joints. This preliminary analysis is concerned with thermal analysis and stress analysis on test specimens which are planed to be used in the machine. Effects of following parameters on temperature/stress distribution of test specimens under various conditions were analysed. Thcse parameters are considered to play significant roles in the analysis of the results of upcoming experiments. (1)Heat transfer coefficient (2)Thermal shock temperature (3)Speed of submerging specimen (4)Comparison of behavior of base metal and welded joint (5)Comparison of mechanical loading and thermal loading
Minato, Kazuo; ; ; ; ; Iwamoto, K.
JAERI-M 9036, 21 Pages, 1980/08
no abstracts in English