This paper proposes two fault detection and diagnosis methods for VAV units without a sensor of supply air volume, and the results of applying these methods to a real building are presented. One method (Method A) detects faults by applying a statistical method to four values calculated using the room air temperatures and the demand values of VAV damper opening of each unit during a steady state operation period. From the results of case studies, the method can reduce the number of units to be checked as faulty ones down to 12% of the total number and all the units that really have a fault are included in this group. The other method (Method B) judges the faults by applying dynamic system analysis to the operational data when the VAV system starts up. From the result of the case studies, the method can detect and diagnose the faults which Method A cannot diagnose properly although Method B cannot detect all the units that really have a fault. If the union of Method A and Method B is used to judge the faults, the method can reduce the number of unit that possibly have faults down to 19% of the total number and can detect and diagnosis properly all the units that really have a fault. Both methods can reduce time and cost for commissioning of VAV units significantly.

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Latent thermal energy storage (LHTES) tanks where carbon-fiber cloths are used to extend the heat transfer area are developed. The tanks are set in an air-conditioning system in a building, and then the performances are evaluated using imitation and practical loads. The results are compared with those of the tanks where carbon fiber brushes are installed. As a result, the carbon cloths of 0.27vol%, exhibit the equivalent thermal performance to the carbon fiber brushes of 1.3vol% during the charge process. The thermal performance of the former is apparently superior to the latter. The effect of the orientation of the cloths in the tanks on the heat transfer rate is also investigated. However it has less influence on the charge and discharge characteristics of the tanks.

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On the steady state flow field. transient concentration responses can be calculated through computation of convolution by using response factors for the pulses of a finite duration. since convective diffusion equation of concentration is linear. Although it is difficult to obtain analytical solution of concentration response for an input pulse of a concentration source on the steady state flow field. numerical responses at any cell can be obtained easily by applying CFD analysis through dividing the flow field into proper cells. In this paper. the calculation method of transient concentration response on the steady state flow field is formulated with reference to the response factor method of air-conditioning load calculation. A computational code is developed on a personal computer based on the present method and simulations for the indoor pollutant accidents are done having some countermeasures for terrorism. The calculation method and simulation results are presented as well as the quantitative effects of all fresh air operation during the accident.

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This paper proposes new method to predict chiller's seasonal energy efficiency. The results from multiple chiller systems simulation had been analyzed in order to find the representing points of COP in chiller operation throughout the year. To estimate seasonal energy efficiency ratio in multiple chiller systems, it is recommended to use only 6 representing points which are classified by part load ratio and cooling water temperature. The CSE index is proposed to predict seasonal energy efficiency of chiller which is installed in multiple chiller system and SCSE index is also proposed to predict system seasonal energy efficiency including chiller accessories, pumps and fans. Weighted harmonic mean method used in CSE equation shows better accuracy with hourly simulation results than conventional IPLV equation which uses arithmetic mean method. This paper also insists the importance of seasonal energy efficiency evaluation in design stage of cooling plant, especially in evaluation of valuable speed pumps.

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The purpose of this paper is to propose optimum thermal comfort zone in floor cooling based on the experimental data. Experiments were conducted under the following conditions in a cooled floor room. There were thirteen combinations of floor surface and air temperature. Air temperature was set to three cases (t_a=25, 27, 29, 31℃). Floor temperature was set three cases (t_f=t_a, t_a-1, t_a-2, t_a-3℃). Relative humidity and air velocity were kept constant level of 60% and less than 0.2m/s. There were sixteen Japanese young female. The following results were obtained. The thermal neutral vote was associated with operative temperature corrected by conduction of 27.0℃ and with mean skin temperature corrected by conduction of 33.7℃. The optimum thermal comfort zone for leg-out sitting positioned Japanese in floor cooling was represented with the operative temperature corrected by conduction of 24.5 to 29.5℃. Floor cooling equipment could set air temperature to a higher side than air conditioning equipment. According to the cooling effect of floor cooling by the heat conduction and thermal radiation, it could contribute to energy saving.

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The purpose of this paper is to propose the empirical formula of convective heat transfer coefficient of the whole body in natural convection. Experimental posture was leg-out sitting position. Experiments were conducted under the following conditions in a artificial climate chamber by using a thermal manikin. Air temperature was set to six cases (t_a=16, 18, 20, 22, 24, 26℃). Wall, floor and ceiling temperatures were set to equal air temperature (mrt=t_a). Relative humidity and air velocity were kept constant level of 50% and less than 0.2m/s. The following results were obtained. The radiative heat transfer coefficient with leg-out sitting posture was 3.555W/(M^2・K). The empirical formula of the convective heat transfer coefficient of the whole body with leg-out sitting posture was represented hc=1.0022ΔT^<0.409>[W/(m^2・K)] where the power of the difference between the mean skin temperature corrected by convective heat transfer area and air temperature (ΔT[K]).

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The monthly energy consumption in the residential sector of ten cities in Kanto, Tokai, Kansai, and Chugoku regions were estimated by using statistical data on family income and expenditures and by using retail price surveys provided by the Statistical Bureau of Japan. The estimated gas consumption was compared with the company's data for investor relations to validate the method used for estimating the residential energy consumption. After the validation, the author focuses on the influence of the weather variables on the residential energy consumption. Based on the results of regression analyses, we presented simple models that use the monthly mean air temperature as input data for predicting monthly electricity and gas consumption per household. Population density should be included as an explanatory variable in the model of gas consumption rate.

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The purpose of this study is an examination of the change in the water quality of the bathtub and the decrease in various disinfectant by taking a bath in the bathtub. The testee targeted university student's male and female. The index of pollution targeted KMnO4, turbidity, the color degree, TOC, and the electric conduction degree. The disinfectant targeted chlorine, chlorine dioxide, and hypobromous acid. The bathing method washes one's body with the detergent, washes one's body with the hot water and does not wash one's body. As a result, the decrease in the density of the disinfectant and the pollution basic unit of each pollution material were obtained according to the kind of the male and female and bathing.

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