A gel ice storage system uses polymer gel as a heat storage substance. The polymer gel keeps the shape as semi-solid of water, and has a large surface of evaporation. The 1kg water vapor evaporation from the gel makes the gel ice of about 7kg at 0℃. A steam ejector evacuates water vapor with motive steams of low temperatures (120〜140℃: under 0.4MPa). We applied the steam ejector to the system to make gel ice. The COP of the experiment was about 0.17 with the motive steam of pressure 0.27MPa and temperature 140℃ during making the gel ice of about 11.5l. We found the following facts; 1) The nozzle exit position in the diffuser is important to get low pressure for the supercooling and making ice. 2) The gel ice storage system with the steam ejector is able to make better use of low pressure steams (0.16MPa to 0.27MPa).

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The development of the fault detection and diagnosis (FDD) system of air-conditioning systems has started as one of IEA-Annex 25 activities. Recently, FDD-WG of the Society of Heating, Air-Conditioning and Sanitary Engineers of Japan and IEA-Annex 34 are holding the development of the FDD system. The stochastic qualitative reasoning (SQR) provides a modelling method of human qualitative thinking process based on the instrumentation diagram and the control information of air-conditioning systems. In this paper, the simulation process of real fault data using the SQR method is reported. In the near future, the SQR will implement the automatic method of fault detection to the computer applications.

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The purpose of this paper is to clarify the use of conductive heat exchange in determining total heat exchange between the human body and its environment. To evaluate a thermal environment, it was necessary to clarify the relationship between posture and conductive heat exchange in humans. The contacted surface area between the floor and the human body was measured on each anatomical suface region, respectively. These measurements were made for eight different postures, including standing, sedentary, sitting upright, sitting with legs crossed, sitting with legs sideways, sitting with knees drawn up, sitting with legs stretched and lateral decubitus. The subjects were fifteen females, whose body types ranged from asthenic to obese. New weighting coefficients for calculating the conductive heat exchange were defined for each posture. Experiments were carried out to evaluate the effect of posture on the conductive heat exchange between the human body and the floor surface. Three female subjects were all exposed to the following combined thermal conditions: air temperatures of 24, 26 and 28℃ and floor surface temperatures of equal to air temperatures, 31 and 35℃. Heat balance in the subjects was estimated by using the new weighting coefficients. Determining the conductive heat exchange may be unnecessary for analyzing the total heat exchange in the standing, sedentary and sitting upright postures, while it may be necessary for analyzing the total heat exchange in the sitting with knees drawn up posture, and it is absolutely necessary for analyzing the total heat exchange in the sitting with legs crossed, sitting with legs sideways, sitting with legs stretched and lateral decubitus postures. Determining the conductive heat exchange is absolutely indispensable for estimating the total heat exchange in postures in which the contacted surface area involved approximately over 2.5% of the total body surface area.

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The energy loss in a pipe fitting with a branching angle of 135 degrees was studied in turbulent flow. To reduce the energy loss, the shape of the pipe fitting with different rounding and chamfering sizes at the up- and downstream edges of the lateral entrance were chosen similar to the branching angles of 90 and 45 degrees. The energy loss coefficients for the flow from the main conduit into the lateral conduit and the straight-through flow and also the power loss coefficient were messured and discussed. As the results, the energy loss becomes smallest when the sizes of rounding and chamfering are the same as those of the width of the lateral conduit similarly to the case of the branching angle of 90 and 45 degrees. The energy loss coefficients for the pipe fitting with rounding are smaller than those with chamfering. The empirical formulae for the energy loss coefficients for the flow from the main conduit into the lateral conduit and the straight-through flow are decided at the above sizes of rounding and chamfering, as expressed by equations (4) to (7). Moreover, the total empirical formulae for the energy loss coefficients for the flow from the main conduit into the lateral conduit and for the straightthrough flow are decided at the above sizes of rounding and chamfering, as expressed by equations (8) to (11).

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In order to design the thermal and humid indoor climate by using condensation and evaporation phenomena on the running water surface of ponds in a large well, the relationship between the condensation rates and the boundary condition [i.e. air velocity, vapor pressure and relative humidity] was found by experimental results using a small model. At the same time, the mechanism of evaporation on the running water surface was discussed as the measurement results by the same analysis method. 1) As the air velocity and the difference of vapor pressure increase, the condensation rates on the running water surface increase. As the relative humidity decreases, the condensation rates decrease. The above relationships were approximated by using the least square method. 2) In a rough estimate, the dehumiditification factor corresponds to the convective heat transfer coefficient. 3) If the cool running water of ponds is designed in a large well, the condensation rates on the running water surface will be estimated by using the above relationships in advance. So the thermal and humid indoor climate in a large well that has a ponds will be improved by condensation phenomena.

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When some faults take place in a thermal storage HVAC system, the changing pattern of the temperature profiles of thermal storage tank is useful to infer where any faults exist. Present study focuses on quantizing this experiential knowledge of fault detection for operators to carry out online fault detection at in various operating control modes of thermal Storage systems. In the present paper, the temperature profiles of the thermal storage tank were calculated using a transient fault simulation program for two kinds of load profiles and three kinds of operating state. Fourier analysis of the temperature profiles was carried out, thereafter. The fault detection parameters obtained from the statistical method proved to be high by effective and the validity of present FDD method was also verified. The twenty four parameters were designed from the experimental data of the temperature profiles. Parameters were classified by the cluster analysis into sixteen clusters and then the most significant pair of parameter for FDD of the present system was selected. Finally the method how the online fault detection and diagnosis would be accomplished was described.

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Average skin temperature and skin wettedness were observed when man felt an equal thermal sensation of warmth. The experiments were carried out using young, healthy, male Japanese students to obtain the values of wettedness and average skin temperature in high-, middle-, and low-humidity environments when they felt an equal warmth. The experiments were conducted on sitting-reading subjects in a test chamber. The subjects were dressed only in athletic short and were exposed to warm conditions for one hour or so. From the analysis of our experimental data, the following conclusions were drawn regarding an equal thermal sensation. 1. Skin wettedness correlates positively with the vapor pressure and correlates negatively with the air temperature. 2. Skin wettedness correlates negatively with the evaporative heat loss from the skin surface. 3. There is a constant relation between skin wettedness and average skin temperature, when man feels an equal thermal sensation. In other words, an equal thermal sensation cannot be indicated merely at constant average skin temperature or at constant skin wettedness as PMV and ET^* define, but it can be determined rather at a constant condition where a kind of modified total of the average skin temperature and the skin wettedness remains constant. Under the above-mentioned condition, the theoretical line of equal thermal sensation obtained from the heat balance equation between the man and the environment is curved line, not a straight line, plotted on a psychrometric chart. The curved line of the sensation "very hot", for instance, shows a small slope down until approximately 50% relative humidity. When the relative humidity is less than 50%, the gradient of the line is steep, and the influence of the humidity on the thermal sensation becomes small.

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Performance of insulation glass is indicated in thermal transmittance of its center for department. But thermal transmittance of insulation glass increases so that the part of its circumference causes heat bridge. A measurement and calculation of theamal transmittance are carried out usually in a uniformity state of the coefficient of surface heat transfer on the cold and warm side. There is possibility changing by performance of insulation glass to surface coefficient of heat transfer. We carried out experiments for a purpose of the following matters. 1. Performance investigation of various kinds of glass. 2. Confirmation of influence range by heat bridge of circumference. 3. Examination of the performances on the center department and an end of insulation glass. 4. Confirmation of influence that performance of insulting glass and temperature difference causes to surface coefficient of heat transfer. The results were as follows: 1. Thermal transmittance of center department were 3.20W/(m^2・K) in 3+A6+3 insulating glass, 2.88W/(m^2・K) in 3+A12+3 insulating glass, 2.75W/(m^2・K) in 3+A18+3 insulating glass. 2. Line thermal transmittance of an end department was 0.044W/(m・K) in 3+A12+3 insulating glass. 3. Influence range by heat bridge of circumference was 5cm in 3+A12+3 insulating glass.

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To control the thermal storage operation properly, it is necessary to predict the heat load of the next day in advance. The present paper focuses on a load prediction method based on Kalman filter through the comparison of load predictions for two buildings with four kinds of applications of it. It has been made clear that the identified load of the present day, out-door temperature and the forecasted highest outdoor temperature are very effective as the input variables in the cooling load prediction, and that the heat load prediction method based on Kalman filter can follow the heat load trend with sufficient accuracy.

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There are various decision factors and processes on the renewal of building facilities. To agree with decision maker, it is important that we show appropriate materials about the necessity of the renewal to them. Generally it costs a large sum of money to renew building facilities so a clear index to evaluate costs and benefits in the case of the renewal should be provided. We defined the level of the effectiveness about the renewal of automatic controllers for air conditioning in 71 buildings as "The Renewal Effectiveness" and analyzed the values by the extended method of the analytic hierarchy process. On the analysis of "The Renewal Effectiveness", we used both quantitative data (maintenance data) and qualitative data (the results of the questionnaire) about the merit and the demerit of the renewal. This report describes a definition of "The Renewal Effectiveness" and the results of the calculation.

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It is believed that in the hot environments, wettedness as well as average skin temperature reveals man's physiological condition accurately. With a purpose to investigate the relationship between average skin temperature and wettedness of man that feels an equal thermal sensation, the experiments were conducted on sitting-resting subjects in a test chamber. The subjects were dressed in athletic short and were exposed to warm conditions for one hour. The results obtained from the present experiments are as follows: 1) The evaporative heat loss from the skin surface correlates positively with the air temperature, while it correlates negatively with the environmental vapor pressure. 2) Wettedness correlates negatively with the air temperature and correlates positively with the vapor pressure. 3) Average skin temperature correlates positively with the air temperature and also negatively with the vapor pressure. 4) Evaporative heat loss correlates negatively with wettedness and correlates positively with average skin temperature. 5) Average skin temperature correlates negatively with wettedness. From the analysis of the present experimental data, the following conclusions were drawn regarding an equal thermal sensation. When subjects voted the thermal sensation "warm", the average skin temperature and the wettedness hold different values depending upon the different combination of ambient air temperature and environmental humidity. In other words, as the humidity gets higher, the average skin temperature goes down and the wettedness becomes larger. In addition a constant relation between average skin temperature and wettedness is observed. Upon calculating the gradients of five different environments from the observed experimental values, we obtained the results stated below. 1) All the gradient values indicate below zero. 2) As the environmental humidity goes higher the absolute value of gradient becomes smaller, and as the humidity lower, the absolute value bigger. It means that both experimentally and theoretically the locus of equal thermal sensation could not be a straight line. Rather it should be a curved line plotted on a psychrometric chart.

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Recently, wooden houses in Hokkaido have become more airtight. As concern for indoor air quality has grown, so too has the need to measure interzonal airflows in houses to assess the distribution of outdoor air. Interzonal airflows betseen rooms are usually calculated by measuring concentrations of tracer gases in each room. Therefore, gas injection methods as well as analytical methods must be discussed for calculating appropriate interzonal airflows. 1) Interzonal airflows by the decay mode should be calculated during suitable times, not just after injection and or at the end of the decay. 2) Interzonal airflows by the constant injection mode can be calculated as fairly stable rates. If it is adopted over a long period of time, interzonal airflow can be calculated as a variable of elapsed time, and it can reduce the causes of errors such as a rounded effect. 3) The integral method under a steady condition can be used to calculate the stable and appropriate interzonal airflow rates over a long period of time. On the other hand, the differential method, during a suitable time, can be used to calculate more accurate interzonal airflow rates than is possible by the integral method. 4) The constant injection mode over a long period of time should be chosen as the tracer gas injection method for field measurements. Either the integral method or the least squares method by governing differential representation should be adopted as the appropriate analytical method in such a case.

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