A model for predicting trajectory of flame/plume ejected from a fire compartment was formulated incorporating the effect of wall above the opening. As observed in the reduced scale experiment, which was reported in the previous paper, window flames/plumes were divided into following categories with regard to trajectory configuration: window flames/plumes which rise almost vertically after ejection maintaining certain separation from the wall; window flames/plumes which rise upward after ejection and attach to the wall in the downstream. In the model, these trajectories were approximated with cubic polynomials respectively, and their coefficients were expressed as functions of a dimensionless parameter F. The parameter F was derived from the conservation equation of momentum, which incorporates the effect of pressure gradient across the current Critical condition for the occurrence of flow attachment was described as a proportion of maximum separation length versus opening width. Trajectories predicted by the proposed model were then compared with the measurement data, and reasonable agreements were obtained.

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Steel is often used as an assembly of main structure such as columns and beams on external walls of buildings. Such steel structural members lose their structural function when the temperature of the steel rises due to spouting hot gas or radiation heating via openings upon fire in a neighboring compartment. This paper presents a calculation model for predicting temperature of steel structural members upon fire heating and proposes it as a practical tool for evaluation of fire resistance. This model also helps the practical prediction of temperature properties of steel structural members that local heating brings about.

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A numerical model for urban fire spread is developed. Proposed model is distinct from existing models in that it explicitly describes fire spread phenomena with physics-based knowledge achieved in the field of fire safety engineering. In the model, urban fire is described as an ensemble of multiple building fires, i.e., fire spread is simulated by predicting behaviors of individual building fires under thermal influence of neighboring building fires. Adopted numerical technique for the prediction of individual building fire is based on the one-layer zone modeling. Governing equations of mass, energy, and chemical species for component rooms are solved simultaneously, to give development of temperature, concentration of chemical species, and other properties. As for the building-to-building fire spread, three phenomena are considered as contributing factors: (i) thermal radiation from fire involved buildings; (ii) temperature rise due to wind-blown fire plumes; and (iii) firebrand spotting. As for the model verification, fire spread simulations were carried out in a virtual urban area, where 2,500 buildings of identical configuration were aligned at constant separations. Calculated fire spread rates were then compared with that of the Hamada-model, and reasonable agreements were obtained.

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The purpose of this study is construction of the evaluation method for easily moving up and down steps in consideration of the interaction of the visual factors, the size of steps and the human characters such as age, height, and foot length. This paper shows the interaction of the visual factors and the size of steps in steady adaptation state, by 14 young girls who are regarded as a same human character. Experimental variables were luminance contrast, illuminance, rise, and tread. The number of steps were 4-5. The interior of laboratory and the surface of steps were matte and white, then the visual field luminance was almost uniform. As the result, it was able to be confirmed that the gradual evaluation structure (Physical value → Physical evaluation → Quality evaluation → the ease of moving up and down steps) is applicable to the evaluation for easily moving up and down steps. In this experimental condition, the effect of visual factors on the ease of moving up and down steps are smaller than the size of steps effect.

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Six boxes designed to measure the mass-transfer coefficient were made, and a variety of construction materials with and without photocatalyst coating on the surface was tested. The test results show that building materials with photocatalyst coating had evaporation effects, and that the surface temperature of the experimental boxes was lower by about ten degrees centigrade and the inside temperature by about seven degrees centigrade on the average when boxes were watered than when they were not watered. It was discovered that water spraying was also effective in reducing the temperature of boxes without photocatalyst coating. The pragmatic standard mass-transfer coefficient in absolute humidity was calculated by testing various construction materials for an extended period of time. Based on the coefficient and dynamic thermal load calculation program, LESCOM-vapor, a simulation on the test boxes and building for experimental use was conducted, and figures obtained from the simulation were found to be similar to actual figures. The LESCOM-vapor program makes it possible to estimate what impact water spraying will have on the thermal environment of buildings.

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A new model has been proposed for evaluating the discharge coefficient and flow angle at an inflow opening for cross-ventilation based on the previous analysis of the flow structure by the Large Eddy Simulation. This model is based on the idea that the cross-ventilation flow structure in the vicinity of an inflow opening creates dynamic similarity under the condition that the ratio of cross-ventilation driving pressure to dynamic pressure of cross flow at the opening is consistent. Wind tunnel model study was carried out to reproduce cross-ventilation by attaching suction fan at the leeward side of the building model. Discharge coefficients at stagnant surrounding condition with suction flow correspond well with those exposed to external wind with extremely large suction flow. Total pressure at the opening is preserved even when flow is separated at the upstream corner. It was confirmed that the proposed model can be applied to almost any directions and opening positions.

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This study discusses the reasons for the inconsistency between the glass and the acrylic desiccator methods which have been used in Japan to classify building materials for the emission rate of formaldehyde. Evidences from experiments showed that the theoretical equations used in the glass desiccator method were not applicable to the acrylic desiccator method. Three-dimensional models for the two desiccators were built for numerical calculations to analyze emission, diffusion and absorption associated with the desiccator methods. The results showed that the time to reach the steady state in the acrylic desiccator method is much long which deviates from the conditions of the equations to apply. Smaller exposed area of the testing materials and larger volume of the desiccator in the acrylic desiccator method are included as the major factors for the delay in the formation of steady state.

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Recently, theoretical analysis and investigations have begun to evaluate that some free radicals are generated by chemical reactions. The free radicals and other products of reactions are often more irritating than their precursors. Especially, the products of ozone/terpene reactions cause greater airway irritation in mice than would be predicted based on the known response of mice to ozone or terpenes. This paper presents an analysis of chemically reactive pollutants in indoor air. We have used a computational fluid dynamics (CFD) technique to simulate bimolecular reactions occurring indoors. Various chemical reaction models have been proposed. The fundamental model is used Rate Constant. In this research, the Second Order Rate Constant model which is a simple model reproducing bimolecular Reaction is adopted. In order to demonstrate the performance of the Second Order Rate Constant models of ozone and limonene, CFD simulations are carried out for a 2D test room. The prediction results of CFD simulation were consistent with the experimental results.

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The aim of this research is to figure out the measuring characteristics about the Large Chamber used to measuring the emission rate of chemical compounds form the home electronics and the furniture. In this paper, the influence of adsorption at wall surface on material transfer rate at each wall of sample are analyzed using CFD and the results of the case that there is wall adsorption and is not are compared and examined. And the area of 10% concentration to instantaneous uniformly diffusion concentration are reviewed and it proposed the measuring method of emission quantity of chemicals which have an adsorption characteristics from sample using the Large Chamber.

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In this paper, we report the experimental studies which were carried out in an experimental house with thermal insulation for its foundation walls, concerning (a) the indoor thermal environment and (b) the heat flow in the crawl space to the ground and to the floor, under the condition of crawl space heating. The main results which we obtained are as follows: 1. The temperature in the room ranges from 18 to 21℃, and that of the floor surface becomes over 23℃. 2. When a fan is put in operation in order to control a current of air in the crawl space, the flow of the heat towards the floor increases, but that towards the ground also increases out of the warm air blowing out zone. 3. It is suggested that most of the heat to the ground is brought by radiation from the lining of the floor.

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There are many reports about faulty status in building air-conditioning systems recently. It becomes difficult to keep indoor air temperature appropriately as faults occur, and the faults cause waste of building energy consumption. The model-based fault detection and diagnosis (FDD) methods have been researched for specific parts of air-conditioning system such as chillers, coils, variable air volume units (VAV units), etc. It needs, however, much time and labor to monitor and check every single part because we can not predict where and when the faults occur. The purpose of this study is to examine indoor air temperature changes and energy consumption increase when faults occur and to develop a prototype FDD tool that helps to find out the faulty place through the whole building air-conditioning system using a knowledge-based method. In this paper, the reliability of the proposed FDD tool and effectiveness to control of indoor environment deterioration and energy consumption increase by the tool are evaluated based on building air-conditioning system simulation.

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In order to upgrade the energy efficiency ratio of a local district, the energy existed in the district is desired to be introduced. In this report, the district heating and cooling plant in Sunport Takamatsu employing the temperature difference of sea water which represents one of the unused energy was surveyed for one year. Then the energy consumption when the plant is not utilized with unused energy was estimated to compare the energy consumption of the systems with and without employing unused energy to determine energy saving effect. In addition, the practically effective energy ratio in consideration with the existing volume of the low temperature unused energy being conventionally employed was obtained to indicate a reference value in planning to employ the low temperature unused energy in future.

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For the purpose of evaluating the performance of water saving fixture, water saving and energy conservation effects of thermostatic mixing faucet and shower head with stop valve were examined by object experiment. The effect of thermostatic mixing faucet compared with two valve faucet was that thermostatic mixing faucet could save water when adjusting hot water temperature and flow rate to optimum condition. The effect of shower head with stop valve was that hot water could be saved by using stop valve on shower head to stop hot water easily when unnecessary. As a result of object experiment, water was saved 1.0L by using thermostatic mixing faucet when hot water temperature and flow rate were adjusted each time to optimum condition. Hot water was saved 14.1L by using shower head with stop valve. Hot water was reduced by 27.3% compared with using normal shower head.

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Individual differences in the ways to perceive residential garden-views were investigated. Japanese and English participants were required to choose the domestic gardens (existing in their own country) from a garden-view picture set presented. Individual Differences Scaling (INDSCAL) was employed to categorize the judged responses by the participants and to reveal a pattern of the categories revealed. Results show that 1) both the Japanese and the English participants could pick up the garden-views in their own countries accurately, 2) an environment inference function worked efficiently on domestic garden-view judgment but not on foreign domestic garden-view judgment, and 3) two dimensions might be used in the garden perception in both the Japanese and the English participants.

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Securing immediate funding for business recovery is indispensable for minimizing economic damage by sudden disasters. The Japanese Government recently issued a set of business continuity & disaster preparedness guidelines where it calls for businesses to plan for quick resumption of operations. There are some existing methods for risk financing, for example, earthquake insurance and alternative risk transfer (hereinafter called ART). However, there is still room for better risk financing methods to be developed. In this paper, the pros and cons of existing risk financing methods are examined. A new method is proposed, combining features of earthquake insurance and parametric triggered ART with focus on minimizing basis risk. A model portfolio of 10 building assets in Tokyo Metropolitan area was applied in analyzing the performance of this method. Through the application, the following findings were obtained; this method allows sufficient risk transfer as provided by earthquake insurance and also enables immediate funding, compared to existing ART methods this method enables lowering the cost by risk takers, hence, this method is attractive for both the recipient and the risk takers and has good possibility to be a new tool for risk financing.

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