This paper describes the unsteady prediction method for the ceiling jet in large building spaces. For the application to unsteady cases, the terms of time differential in the government equations and the one dimensional heat transfers in the ceiling were added to the Alpert's theory. Moreover some of the functions such as the friction force against the ceiling and the air entrainment rate were refined for improving of the accuracy and the coverage. By this model, the profiles of the velocities, the gas temperatures and the heights of the ceiling jet are computed as time sequential, considering the influence of the heat loss into the ceiling and the dilution by the air entrainment. The result of a prediction was compared against Alpert's and Heskestad's practical correlations and the basic performances were confirmed. In the final part of this paper, the comparison of the predictions by this model was performed against measurements in a case of fire experiment using a large building space for validation.

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We conducted a survey about signage setting conditions of escape routes in some public transport facilities using measurement method of configuration factor in the evacuee's visual field constructed in our previous research. The survey was done at international airport terminals and subway stations in Japan and Thailand. Moreover we also did subjective evaluation experiments (easy-difficult to find escape routes) at the same points with the survey about signage setting conditions. And then the relational expression between sign's configuration factors and ease ofwayfinding was derived by the multiple regression analysis. Finally we evaluated the effects of signs installation for evacuation using the survey results and the evaluation equation..

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Heat insulation specifications of the fitting which combined a Taiko-shoji with wooden pair glass sash are effective as the way of repairing a traditional wooden house with not only heat insulation performance but also the execution and design as well. In this paper, the insulation performance of Taiko-shoji was examined by indoor experiment, actual house measurement and numerical calculation. The results are as follows. As the result of indoor experiment, the heat resistance value of Taiko-shoji (air space=26mm) was at 1.3 times of single shoji and about 20% of the heat transfer coefficients decreased. As the result of measurement of improved actual house, the average heat resistance value of Taiko-shoji + pair glass was 0.64 m²·K/W, pair glass only was 0.35 m²·K/W. The overall heat transfer coefficient of Taiko-shoji + pair glass decreased to 27% of single glass by the numerical calculation. In case that the traditional house with single glass is repaired by Taiko-shoji + pair glass fitting, the validity of these specifications is shown by the simulations.

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Double-skin façade is a technique covered with glasses the building exterior, it can realize energy saving as well as highly transparent façade. From these perspectives, the installation of double-skin façade for office building has increased in recent years. The design of the recent focus on life cycle assessment needs annual or seasonal performance characteristic for the double-skin façade as well as a performance characteristic on peak load.
In this study, the thermal performance of double-skin façade was described by using field measurements survey and simulation results. Solar shading coefficient (SC) value and thermal transmission (U) value can describe solar heat gain of double-skin façade. The prediction method for SC value and U value was introduced, can predict the thermal performance considering the seasonal fluctuation.

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Variation of discharge coefficients with wind direction and opening position is one of the main factors decreasing accuracy of cross-ventilation flow rate prediction. The local dynamic similarity model was developed to solve this problem, and previous papers had validated it for inflow openings. In the present study, two experiments and a CFD analysis were carried out to investigate its validity for outflow openings. The study showed that discharge coefficient was not always determined uniquely by the dimensionless room pressure P_R^*, and there were two types of relationship between discharge coefficient and P_R^*. The difference of the relationship was attributed to the thickness of external airflow layer, which passed tangentially to the opening. Therefore discharge coefficient could be predicted from P_R^* if either type of relationship was appropriately adopted according to the thickness of external airflow layer in each case. In addition, this study also showed the definition of dynamic pressure tangential to outflow openings, which is necessary to determine the P_R^*. It can be concluded from the study that the local dynamic similarity model is valid for outflow openings as well as inflow openings.

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A model was proposed to evaluate correlation of turbulent fluctuations of reactors' concentrations. It enables adequate prediction of the pollutant dispersion with bimolecular chemical reaction using RANS type turbulence model. It is composed of turbulent kinetic energy (TKE), dissipation rate of TKE, spatial gradients of mean concentrations, and a model coefficient. The model was validated against LES of dispersion and bimolecular chemical reaction in a turbulent channel flow. It was confirmed that the model could predict accurately the correlation except near-wall region. Although the model coefficient had a Reynolds number dependency, it reached a finite value (nearly 0.05) in high Reynolds number region. A test calculation with a RANS type turbulence model employing the proposed correlation model was also conducted. It was found that it could make improvements in the prediction of the reaction rate.

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This study has two objectives: to understand the drainage performance of a high-rise stack drainage system when air-admittance valves are installed; one in the vent pipe section and another in the horizontal fixture drain branch section, and to consider a method for predicting the drainage performance of the system by suggesting a pipe network model. This report first aims to identify the basic characteristics of the pipe pressure in relation to the airflow rate through a drainage load experiment in which air-admittance valves are installed; one in the vent pipe section and another in the horizontal fixture drain branch section of a stack drainage system, and air is drawn in from the installation locations. The report then proposes a pipe network model for predicting the aforementioned airflow rate and pipe pressure, estimates the drainage performance from analysis results, and examines the validity of the prediction method.

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Research questionnaire was carried on the usage of housing equipment focusing on the continuous ventilation system in apartment houses. It was confirmed that ventilation systems are operated 24 hours more than 80% of the respondents, and the operating ratio increases as the household number increasing. On the other hand, the ratio of opening outdoor air inlets for ventilation system was as low as about 50%. Cross correlation analysis showed that the operation of continuous ventilation system is effective in suppressing dew condensation, mold and bad smell, and the majority of respondents evaluate the ventilation system satisfactorily. Separate analysis by age revealed that aged households are very sensitive on utilities expense and tend to apply local heating of a room and bathing is not frequent.

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Sensitivity of boundary layer parameterizations to atmospheric stability preceding heavy rainfall is investigated using the 5^th-generation NCAR Mesoscale Model (MM5). Four turbulence parameterizations [MRF, Blackadar, Gayno-Seaman and Eta] and four surface flux schemes [Carlson-Boland, Garratt, Zilitinkevich and Janjic] are selected for evaluation. The Carlson-Boland surface flux scheme produces deep convection and causes hot and dry boundary layer regardless of the turbulence parameterizations. The combination of the MRF turbulence parameterizations and the Garratt surface flux scheme well reproduce local heavy rainfall which observed at Tokyo on 15 August 2005.

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Improvement of outdoor ventilated environment contributes not only to energy-saving and suppression of CO₂ but also to indoor air quality and its comfort. To consider outdoor well-ventilated environment, a flow field within ideal urban canyons has been investigated by wind tunnel experiment, but the behaviors of turbulence and mean characteristics of canyon vortices within real urban canyons are still not comprehended. In this study, a wind tunnel experiment for a real apartment complex was conducted to confirm the reproducibility of flow field within the canyon. The apartment complex is located at Musashino city, Tokyo, where field measurement was conducted. The buildings with a height more than two-stories were resolved within 200m radius under the model length ratio of 1/150 was measured using both PIV (Particle Image Velocimetry) and LDV (Laser Doppler Velocimeter). These measurements at 5 points within the urban canyon were compared with field measurement values. The wind velocities and turbulent intensities obtained by both PIV and LDV fairly agreed with the field measurement values within the urban canyons, though a small-scale surface roughness like a balcony was not modeled in the present wind tunnel experiment.

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Today, the reduction of energy consumption is a national critical issue. The saving energy in buildings has become a burning question, and many buildings adopt the energy-saving technologies now. However, small buildings less than 2000m² in total floor area seem to be still backward in saving energy, and very little energy consumption data of these buildings was made public. This paper shows the data of energy consumption and the thermal environment of these buildings through field studies for three years. When the data of small buildings investigated this time is compared with the data of large buildings that has already been made public, there are different features in small buildings and large buildings.

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