This study was aimed to give new empirical equations for predicting the overall thermal comfort and local thermal discomfort for sitting people in the non-uniform thermal environment. The aimed equations were derived by the multiplying local thermal states calculated using the local skin temperatures and local dry (sensible) heat losses, which had been reported in the previous papers in this series. The empirical equations are applicable to evaluate the overall thermal comfort, thermal discomfort for hot head and/or hot whole body, and thermal discomfort for cold foot (including the leg in the same side) and/or cold whole body for sitting people in the non-uniform thermal environment. The characteristics of the equations can be summarized as follows. The level of the overall thermal comfort decreased when the whole body was extremely heated or cooled and the distribution of the thermal states similarly deviates from a fixed distribution. According to this fixed distribution, the level of the overall thermal comfort will become higher when a human is located in a uniform environmental condition, and decrease together with the increase in the front/back and right/left asymmetries. However, this distribution also indicates that the precision of the equation will decrease when in the up/down asymmetric conditions. The level of the thermal discomfort for hot head and/or hot whole body characteristically will increase with the extent of heat in the head and the whole body. The level of the thermal discomfort for cold foot and/or cold whole body will characteristically increase with the extent of coldness in the foot and the whole body. In order to validate these three empirical equations, experiments were conducted under the up/down asymmetry radiant environment with the clothing condition different from the basic experiments. With regard to the overall thermal comfort, although the calculated comfort levels were similar to the mean levels of the whole subjects, in some cases, the equation cannot sufficiently reflect the influence of the up/down asymmetries. With regard to the thermal discomfort for hot head and/or hot whole body, both calculated discomfort level and measured level were generally small under the experimental conditions and they took the similar values. With regard to the thermal discomfort for cold foot and/or cold whole body, the equation was inclined to overestimate the discomfort level for male subjects, and contrarily for female subjects. However, the calculated levels agreed with the mean levels for the whole subjects, and also, it showed the same inclination on the change of the discomfort level corresponding to the environmental conditions, just as that found in the experiment.

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In the past studies, we proposed a new type of desiccant air-conditioning which combined with a CO_2 heat pump, and the system was evidenced with lower energy consumption than conventional air-conditioning systems. But in these studies, the proposed desiccant air-conditioning system is considered providing only dehumidification and cooling usage. However, the system can be used in reverse for humidification/heating to deal with the cold and dry climates, such as the winter period of Tokyo. In this paper, a desiccant air-conditioning system providing humidification and heating usage is proposed, and two kinds of system flows of the proposed system are studied experimentally. In this system, vapor from the outdoor air is the moisture source, and the heating and humidification power is sufficient under the weather in early March in Chiba city. With different regeneration temperature and flow rate ratio between adsorption side and humidification side, heating and humidification power are possible to be controlled to fit the load of the buildings. Furthermore, we compared the energy consumption between the CO_2 heat pump combined desiccant air-conditioning system and a conventional system under the same humidification/heating conditions. The result shows that the proposed system can provide 24% at the maximum energy saving effect.

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The energy system simulation program such as BECS/CEC/AC and HVACSIM+(J) are used for the calculation of the energy consumption. These existing programs require that a user makes for each pump an approximate characteristic expression of pump capacity. Making the expression is a time-consuming job. This paper propose characteristic expression not to depend on pump capacity. The following three findings were chiefly obtained. 1) The approximate characteristic expression is a function of flow ratio which is normalized by the flow rate of highest efficiency point. 2) The expression is applicable to ratings flowing quantity 0.17-12.5m^3/the minute. 3) The error of obtained polynomial is less than ±10% for the flow ratio 0.4-1.3.

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Several types of ceiling air diffuser form the attached air jet along the ceiling which diffuses throughout a room. However, if the layout of supply openings and exhaust ones is not appropriate, the short circuit between them appears and ventilation/air-conditioning efficiency becomes very low. Additionally mixing loss between interior zone and perimeter zone may occur and make energy consumption. In this paper, flow visualization test was conducted in the office and the problems described above were confirmed. Then CFD simulations were carried out to study adequate layout of openings for HVAC system.

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