CFD prediction of flowfield and snowdrift around building complex in snowy region

A CFD ( Computational Fluid Dynamics) technique is applied to the prediction of snowdrift around a 9-storey apartment building. A modified version of the Launder-Kato-type k-εmodel (LK model[5,9,10]) is used. In the first part of the paper, results of a preliminary study for a flowfield around a cube placed in a channel flow are presented. Here, results obtained by using the modified LK model are compared with those of measurements and the standard k-ε model. The latter part describes the numerical prediction of snowdrift around a 9-storey apartment building which is presently under construction in Nagaoka City, Niigata Prefecture. Special emphasis is given to snowdrift into the elevator hall

Numerical Analysis of Outdoor Thermal Environment in City Block Area Using Coupled Simulation of Convection and Radiation -Part 2 CFD Study on of Outdoor Thenna1 Environment sing Modified κ-ε model -

In this study, velocity, temperature and humidity fields in urban area were analyzed using CFD technique developed by the authors. Spatial distribution of SET* is calculated in order to assess pedestrian comfort from the CFD predictions. It was darified that 1) revised κ-ε model can predict the velocity field and temperature field more accurately　than does the stndard κ-ε model， 2) greening is effective for relaxation of thermal environment on the urban area in summer，3) coupled simulation of radiation and convection with incorporating of moisture transport is very powerful tool for eva1uating the outdoor environment

Numerical Analysis of Outdoor Thermal Environment in City Block Area Using Coupled Simulation of Convection and Radiation -Part 2 CFD Study on of Outdoor Thenna1 Environment sing Modified κ-ε model -

In this study, velocity, temperature and humidity fields in urban area were analyzed using CFD technique developed by the authors. Spatial distribution of SET* is calculated in order to assess pedestrian comfort from the CFD predictions. It was darified that 1) revised κ-ε model can predict the velocity field and temperature field more accurately　than does the stndard κ-ε model， 2) greening is effective for relaxation of thermal environment on the urban area in summer，3) coupled simulation of radiation and convection with incorporating of moisture transport is very powerful tool for eva1uating the outdoor environment

CFD Analysis of flowfield around building using revised k-ε models based on mixed time-scale

The flowfields around a front-step and a cubic shaped building model placed within the surface boundary layer were analyzed by using various k-ε models; namely standard k-ε, Durbin’s revised k-ε and revised k-ε with mixed time-scale concept. The calculated results are compared with those of wind tunnel experiment. Turbulent kinetic energy k around the windward corner is overestimated by the standard k-ε and the Ω type revised k-ε models, while it is improved by the S type model and the model proposed by Durbin. However, all revised k-ε models overestimate the reattachment length behind the building in comparison with the experimental data

CFD Analysis of flowfield around a high-rise building using various revised k-ε models

The flowfield around a high-rise building model placed within the surface boundary-layer was analyzed using various revised k-ε models, and these results were compared with the result of DSM and the experimental data. The standard k-ε model could not reproduce the reverse flow on the roof. This drawback was corrected by all revised k-ε models and DSM tested here. However the revised k-ε models except for the model proposed by Durbin overestimated the reattachment length behind the building in comparison with the standard k-ε model. Among the computations using various turbulence models compared here, the result with the Durbin’s revised k-ε model showed the best agreement with the experiment

Numerical Analysis of Local Climate in Niigata Area

Velocity and temperature fields in Niigata area were predicted numerically using the turbulence closure model developed by Mellow and Yamada. Two cases of predictions were carried out. In case 1, the present situations of land-use were incorporated into the prediction through the boundary conditions at the ground surface, while values of surface parameters in the area of rice field were changed to the values corresponding to the paved road in case2. Effects of the rice field on local climate in summer season were discussed by comparing the results of these two cases

Sequencing and Analysis of Approximately 40 000 Soybean cDNA Clones from a Full-Length-Enriched cDNA Library

A large collection of full-length cDNAs is essential for the correct annotation of genomic sequences and for the functional analysis of genes and their products. We obtained a total of 39 936 soybean cDNA clones (GMFL01 and GMFL02 clone sets) in a full-length-enriched cDNA library which was constructed from soybean plants that were grown under various developmental and environmental conditions. Sequencing from 5′ and 3′ ends of the clones generated 68 661 expressed sequence tags (ESTs). The EST sequences were clustered into 22 674 scaffolds involving 2580 full-length sequences. In addition, we sequenced 4712 full-length cDNAs. After removing overlaps, we obtained 6570 new full-length sequences of soybean cDNAs so far. Our data indicated that 87.7% of the soybean cDNA clones contain complete coding sequences in addition to 5′- and 3′-untranslated regions. All of the obtained data confirmed that our collection of soybean full-length cDNAs covers a wide variety of genes. Comparative analysis between the derived sequences from soybean and Arabidopsis, rice or other legumes data revealed that some specific genes were involved in our collection and a large part of them could be annotated to unknown functions. A large set of soybean full-length cDNA clones reported in this study will serve as a useful resource for gene discovery from soybean and will also aid a precise annotation of the soybean genome

Characterization of Geographical and Meteorological Parameters

[EN]This chapter is devoted to the introduction of some geographical and meteorological information involved in the numerical modeling of wind fields and solar radiation. First, a brief description of the topographical data given by a Digital Elevation Model and Land Cover databases is provided. In particular, the Information System of Land Cover of Spain (SIOSE) is considered. The study is focused on the roughness length and the displacement height parameters that appear in the logarithmic wind profile, as well as in the albedo related to solar radiation computation. An extended literature review and characterization of both parameters are reported. Next, the concept of atmospheric stability is introduced from the Monin–Obukhov similarity theory to the recent revision of Zilitinkevich of the Neutral and Stable Boundary Layers (SBL). The latter considers the effect of the free-flow static stability and baroclinicity on the turbulent transport of momentum and of the Convective Boundary Layers (CBL), more precisely, the scalars in the boundary layer, as well as the model of turbulent entrainment