T字配管合流部に生じる温度変動の数値解析による評価LES Dynamic による格子影響評価一
Numerical Simulation of Temperature Fluctuation Downstream from a T-Junction-Evaluation of Computational Grid Influence Using LES Dynamic Model
著者:
歌野原 陽一 Yoichi UTANOHARA 中村 晶 Akira NAKAMURA 三好 弘二 Koji MIYOSHI 笠原 直人 Naoto KASAHARA
発刊日:
公開日:
Computational gridMixing teeNumerical simulationTemperature fluctuationThermal fatigue
概要
Abstract Thermal fatigue crack may initiate at mixing tee where high and low temperature fluids flow in and mix. In order to prevent piping failure caused by thermal fatigue, an evaluation procedure of fluid temperature fluctuation at mixing tee using numerical simulation has been de veloped. This paper compared results of three computational grids of different resolution and discussed the effect of the grids resolution on predictions. The same simulation conditions were set same as WATLON experiments performed at Japan Atomic Energy Agency: wall jet condition th at the jet from the branch pipe flowed along the main pipe wall. Time-averaged temperature distributions with different grids almost agreed well with the experimental results. Each grid overestimated fluctuation temperature than the experimental result, that is, all of the grids can be used to evaluate conservative result. Hence, the coarsest grid of them seems to be enough for practical use. Predicted results seem to be affected by not only overall but local grid resolution and it is preferable to optimize the grid resolution according to the target flow fields.
