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In this paper, two new indices, CRP1 and CRP2 (Contribution Ratio of Pollution Source 1 and 2), are proposed for evaluating the contribution of an indoor pollution source to human's breathing air quality. CRP1 refers to a ratio indicating how much of the contamination from a pollution source will be inhaled, and CRP2 refers to a ratio indicating how much of the total inhaled contaminant will be from a pollution source. Moreover, CFD methods for the two indices are developed to investigate the breathing air quality of a standing occupant or a lying occupant located in a stagnant room, which is assumed to be air-conditioned by means of displacement ventilation. The results indicate that in such a room, less of the contaminant from the above space will be inhaled by either standing or lying occupant, and it is important to make the floor clean for preventing breathing air from being polluted as expected.

In response to amplifying the problems of global environment, the municipality has been expected to take integrated countermeasure to contribute to building of a sustainable society. Tokyo metropolitan government draws up the guideline of government building planning to design the building considering the environment. This paper introduces a developed evaluating system in order to confirm consideration level of guideline by calculating some life cycle indices and grading a casbee tool. We can analyze the effect of reduction CO_2, emission and cost-benefit on public facilities, public high school and public hospital by adoption of environmental technologies by using the indices.

Computational fluid dynamics (CFD) analysis using a low Reynolds number k–ε model was performed to examine the inhalation region of a human body in a stagnant environment. To account for the influence of the three-dimensional form of the human body, a model that replicated the actual forms of a real human body was used. CFD analysis was applied first to a room model with an occupant. The inhalation region under steady-state conditions was examined with the assumption of steady inhalation. Subsequently, an unsteady breathing model was introduced and the respiration area was analyzed. The variation of the air-velocity distribution, the influence of the exhaustion on the inhalation was examined, and the inhalation region under unsteady-state conditions was also analyzed in detail. In this study, the inhalation region of an experimental thermal manikin was also examined by a tracer-gas experiment using a high-response flame ionized detector (FID). The thermal manikin was assumed to perform steady inhalation in the experiment. Results of simulation can be considered to agree well with the experimental results, and the CFD method using a human body with a complex shape is shown to be effective in studying the inhalation region.

The purpose of this study is to make a database of the local convective heat transfer coefficients (h_c)for each part of a human body in indoor environments. Values of the local h_c for a naked human body are determined based on both the results of experiments on a thermal manikin and analyses of the radiative heat transfer rate. The results are followed. (1) At the extreme parts of the human body, h_c is about 1.5W/m^2K higher than the average value for the whole body, and for the trunk parts are about 1.0W/m^2K lower than the average values in the state of standing and sedentary. (2) The value for the local h_c decreases as the human body approaches the furniture.

In this paper, the flow field in human's respiration area was examined through the PIV (Particle Image Velocimetry) experiment using an experimental thermal manikin and CFD analysis, with the assumption of steady inhalation and unsteady breath. In the CFD analysis, the variation of the air-velocity distribution, and the influence of the exhaustion on the inhalation were examined in detail. Moreover, to account for the influence of the three-dimensional forms of the human body, a model that replicated the actual forms of a real human body was used in the simulation. It indicates that each breathing cycle can be taken as an independent process and the real breathing can be assumed as steady inhalation in CFD analysis on inhaled air region. Moreover, the CFD method using a human body with a complex shape indicates to be effective in the study on the flow field in human's respiration area.

A calculation tool is developed to estimate reduction in CO_2 emission from Governmental facilities and schools constructed according to Aomori Prefectural Guideline on Environmentally friendly Architectural Design. This simplified LCA tool, that also calculates initial and lifecycle costs, is so easy to operate that user only select measures to reduce environmental loadings through planning process. CO_2 emission from governmental facilities by the year 2010 was predicted with combination of the environmental techniques used in new construction, existing buildings and renovation projects. The Aomori government increased its budget as additional cost to introduce these measures for new construction of governmental facilities

CFD analysis was performed to examine the characteristics of contaminated indoor air ventilation in a simplified two-dimensional room model. To evaluate the effectiveness of exhaust openings, we introduced a new index, IECV, showing the effectiveness of contaminant ventilation, using the product of the concentration of the contaminant in the air and the portion of the air vented from an exhaust opening. We then applied these concepts to the more realistic case of inhalation by a human occupant in a room with three-dimensional CFD, assuming the human mouth at inhalation to be an exhaust opening. It was found that the region of inhalation was greatly influenced by the rising stream of air resulting from the heat generated by metabolic activity. Corresponding to the index IECV, we defined another new index, IECI, showing the effects of contaminant inhalation. Using IECI and other factors, the characteristics of contaminant inhalation by an occupant in the room were examined in detail for some common human postures.

In this paper, new indices for evaluating the inhaled air region are proposed. It expresses that the part of the room air which is going to be inhaled by a human body. Indoor air pollutants such as VOCs generated from building materials are transported by room air convection and finally exhausted through the outlet opening. In the process of room air convection, some portion of the pollutant is inhaled by the human body. The human body is covered by rising stream around it. It is generated by a heat discharge due to metabolism. The mechanism of inhalation is greatly influenced by the rising stream, in order to analyze the inhaled air region in a room, we should take into consideration this rising stream around a human body. This paper analyzed the inhaled air region in consideration of human body in three different postures by means of CFD analysis. When human body is standing, human body inhales the air of the lower part of room because the rising stream which generated by metabolic heat draws the air from the lower part of the room to the breathing area of human body. When sitting, inhaled air region distribute the lower region from the mouth like in standing posture. When sleeping, the inhaled air region is distributed over the horizontal direction of the mouth near the floor.

This research aims to analysis the flow field and the transportation of contaminants around the respiratory region.In this paper, the flow field around respiratory area of breathing thermal manikin is measured by PIV (Particle Image Velocimetry) system.The experiment is performed in a chamber controlled stagnant state with constant temperature.Respiratory conditions is set three different cases, inhalation and exhalation all the time, and inhalation and exhalation in turn.In result, in the case of inhalation steadily, the thermal manikin inhaled air transported from the lower space of the mouth.And so, in unsteady respiration case, thermal manikin inhaled air from same space with the case inhaled air steadily.This result verified the validity of having performed steady analysis of the flow field around the respiratory area in numerical computation.

The purpose of the paper is to analyze passive-smoking in a room with 3-dimensional CFD analysis. We examine how much the breathing/inhalation air region is polluted by the smoke blown from a smoker's mouth or by the smoke arising from a lit cigarette. We evaluate the degree of pollution around the nose and mouth considering the indices of ventilation effectiveness. Displacement ventilation and mixing ventilation are tested as a ventilation system of the room. In the case of displacement ventilation, we examine two cases with the different speed of exhalation velocity. We observe that the thermal plume caused by the metabolic heat generation of the smoking person effectively transports both the cigarette smoke and blown smoke from the mouth upward and thereby the opposite-side person (passive smoking person) is not affected so much by the smoke. High-exposure case occurs only for the case with the high speed exhalation velocity and with the close distance between smoking and passive smoking person. On the other hand, in the case of mixing ventilation, the smoke tends to diffuse uniformly within the room regardless of the distance of the two persons.

The thermal and dynamic effects of wind on a human body are analyzed by means of computational fluid dynamics (CFD) technique. Wind effects on a human body are examined under various wind conditions. At first, the human body is placed in a stagnant wind environment. Secondly, the human body is set in a weak wind of velocity 0.25m/s, with several values of turbulence intensity. Next, the wind velocity attacking the human body is increased to 2.5m/s. Lastly, two human bodies are arranged standing in a row, facing the approaching wind. The velocity and temperature fields around the human body as well as the pressure field over the body surface are computed in detail. The drag coefficient and the convective heat transfer coefficient of the human body are calculated. The predicted results of velocity and temperature fields agree reasonably with previous experimental data.

Indoor air quality is greatly affected by the emission and sorption of chemical compounds from building materials such as VOCs (Volatile Organic Compounds). This paper presents physical and mathematical models and CFD (Computational Fluid Dynamics) analysis of VOCs transportation from the micro scale (inside building materials) to the macro scale (within a room). Furthermore, the micro climate around a human body is analyzed from the viewpoint of inhalation of chemical compounds. In the micro scale analysis within building materials, physical models of diffusion and sorp- tion of VOCs, which is based on the fundamental physicochemical principles, are proposed. Long-term diffusion analyses in building materials are carried out based on the model equa- tion. In the analysis of experimental chamber scale, the emission and diffusion of chemical com- pound within a FLEC (Field and Laboratory Emission Cell) is investigated as the case study of CFD analysis, using the proposed physicochemical models. The problems of emission testing methods using a FLEC are clarified through this CFD analysis. In the analysis of room scale, the performance of the proposed physical models is evaluated quantitatively in a test room using the technique of CFD. The results of the numerical analysis show that the physical models and their numerical simulations effectively explain how VOCs are generated and transported in a room. Lastly, the inhalation of contaminated air by a human body is analyzed by CFD. New indices for evaluating the contribution ratio of pollutant source to inhaled air are proposed.