Influence of secondary flow generated in a 90-deg bend on the thermal-hydraulic characteristics in a mixing tee

Yuki, Kazuhisa*; Sugawara, Yoshimasa*; Hosseini, S. M.*; Hashizume, Hidetoshi*; Toda, Saburo*; Tanaka, Masaaki; Muramatsu, Toshiharu

Nuclear Science and Engineering, 158(2), p.194 - 202, 2008/02

https://doi.org/10.13182/NSE08-A2746

This study aims at clarifying a relationship between non-isothermal fluid mixing in a T-junction area with 90-deg bend upstream and temperature fluctuations induced by the unstable mixing, by visualizing the flow fields with particle image velocimetry and measuring fluid-temperature fluctuation in the vicinity of a wall. By the experiment, flow-pattern of the jet flowing out from a branch pipe and characteristics of temperature fluctuation in mixing area were clarified in relation to the secondary flow generated in the 90-deg bend.

Study on Configuration and Structure of Faults

Sugawara, Masaaki*; Maruyama, Toru*; Kambara, Hiroshi*

JNC TJ7420 2005-047, 79 Pages, 2003/03

JNC-TJ7420-2005-047.pdf:12.71MB

Configuration and structure of the ore veins of the Toyoha mine, which occur in faults, were studied with the purpose of developing methods for investigating the effect of fault movement to groundwater flow. Information on the shape of the veins were acquired and analyzed. Plane vein maps in some levels and cross sections of four representative vein systems (Tajima-Harima, Izumo-Shinano, Soya, Sorachi) of the Toyoha ore deposit were scanned, and three-dimensional features of vein distributions were recorded as image data. Morphological characteristics of typical veins of the Toyoha ore deposit were extracted from vein maps, geological and mineralogical cross sections and vein sketches. A tendency of vein-shape changes is recognized from the upper to the lower parts; cymoid curve with strong lensing, gentle cymoid curve with relatively constant width, linear vein with relatively constant width in ascending order of depth. This is thought to be a morphological characteristics of shear fracture formed in correspondence with increase of confining pressure. Distribution of vein trace length of the Toyoha mine exist within the range of uncertainty in the figure between fracture trace length and cumulative number of fractures indicated by Ohtsu (2001). Thus, accumulated number of fracture trace length is thought to be in linear relation irrespective of size, region and rock ype.