The air volume which is necessary for control the smoke at the time of fire is determined by meteorological conditions such as temperature, direction of wind, closing state of windows and so on, which is characteristic for individual building. Therefore, in order to decide a smoke control system that is optimum for a certain building, it is necessary that, by varying those conditions of the building, thereby an investigation whether the building is capable of enduring the aforementioned various conditions or not should be done. The air-flow calculation in a large-scale building requires much time ever though a computer is employed, so that it would be almost impossible in practice to calculate for all of the numerous conditions. Accordingly, the authors prepared a program of simplified calculation which enable to compute on the numerous conditions. The present paper shows six control systems as means of stairshafts or their lobbies free from smoke. Six control systems to keep the stairshafts and its lobby free from smoke are discussed and we can find some effective smoke control systems for high-rise building in them.

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The purpose of this paper is to investigate the fundamental characteristics of the cabinet room heaters. The model heaters used were consist of so-called "Convector" and the electrically heated vertical rectangular fins. The dimensions of the fins were 5 or 10cm high, 50cm wide and 3.5mm thick, and the numbers were twelve or twenty two. The spaces between fins were changed 3〜10mm and were set at the bottom of convector. The heights of the convectors were 23, 38 and 63cm. The base and the top of the convector were open and the air flow were completely vertical. In each experiment, the temperature difference between fin surfaces and inflow air was kept about 70℃. The following results were obtained. 1) The average heat transfer coefficients by convection were nearly equal independent of the number of fins. 2) The average heat transfer coefficients in our experiments were considerably larger than those of the Elenbaas's or Aihara's results on two vertical parallel plates by free convection because of chimney-like action of convector. 3) There was the optimum fin spacing for the maximum heat transfer rate per base area of convector when the experimental conditions were fixed other than the spacings. The optimum spacings were narrower for the increasing heights of convectors or for the decreasing heights of fins and were 4〜6mm within the range of this experimental conditions. The authors carried out the theoretical analysis of the model heaters. The method of analysis is similar to the one by Bodoia et al. which was reported closely agreed with the experimantals of Elenbaas or Aihara. The calculated average heat transfer cofficients agreed with these experimental data for the fin spacing more than 6mm, but less than that the analytical values were considerably higher. The reasons for these discrepancies were proved to be mainly the turbulents at the narrower spacings which were found out by the visual study of flow pattern.

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In order to save energy resources it is about to take up as an urgent problem to use effectively every kind of energy, not to mention thermal energy. Until comparatively lately, from economical estimation we have never made positive use of waste gas energy at low temperature level, to say nothing of solar energy, for instance. Of cource energy saving is a fine thing, but considering future prospect of increasing energy consumption and thermal pollution, etc., besides this it is necessary to consider how to use effectively the unused energy resorces which have frequently been neglected. From such a point of view it is natural the matter of energy storage becomes a subject of discussion, and as a matter of course thermal energy storage belongs to the category of the subject. Now, heat energy storage methods mainly adopted hitherto depond on the use of heat capacity of the materials, such as sand, rock and water or on the use of latent heat of fusion or phase-change of inorganic substances or eutectic salt mixtures. However, these ways of energy storage are not always high for energy storing density and what is worse, though these are of course useful for short-term storing, incompetent for long-term because of heat loss taken place by maintaining the materials under high temperature level, even if adequate thermal insulation are performed. Under such situations, in order to avoid the faults a new heat storage method is proposed in this paper. This way which is based on the ues of reversible chemical reaction cycles makes not only long-term heat storage but also high energy storing density possible. Furthermore, in this paper the principles of this method and results of basic experiments are reported. At any rate, there remain still many unsolved problems for putting this way to practical use, but as a new method which makes up for the weakness of the previous its coming development are expected.

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In the first report, it was shown that the factors which influenced on the dispersion of warm water into a rectangular open channel were Reynolds number, Froude number, the densimetric Froude number, the velocity ratio, the heat loss from the water surface, and five geometrical boundaries. They were derived by rewriting the equations of continuity, momentum, and energy, and boundary conditions to dimensionless forms under several reasonable assumptions. Above ten dimensionless factors influence on the temperature distributions, the decrease of maximum temperatures, the areas within iso-concentration contours in the cross sections of a open channel, the volumes within iso-concentration contours, etc.. In this paper, the influences of three dimensionless groups, which were the densimetric Froude number, the velocity ratio, and Froude number, were investigated experimentally. The experiments descrived herein were performed in three rectangular open channels 400cm long by 20cm wide by 10cm deep, 400cm by 15cm by 7.5cm, and 400cm by 10cm by 5cm, and in the following range of four dimensionless groups: the densimetric Froude number=0.68 to 2.53; the velocity ratio=0.24 to 2.17; Reynolds number=1370 to 4020; Froude number=0.088 to 0.174. The measurements of temperatures were made using Cr-Ar thermocouples of 0.1mm in diameter and a commercially available multipoint digital voltmeter, which was capable of measuring up to 50 variables. The flow rates in a open channel and of warm water were measured by means of rotormeters. The temperature of warm water and the flow rate of warm water were controlled within the range of ±0.15℃ and ±0.025l/min respectively. The main experimental results are as follows: (1) The influences of the densimetric Froude number The decrease of maximum temperatures becomes large in proportion to the densimetric Froude number. The maximum values of the areas within iso-concentration contours in the cross sections of a channel change not so much for the densimetric Froude number, but the volumes within iso-concentration contours become large with the decrease of the densimetric Froude number. (2) The influences of the velocity ratio The maximum temperatures become high with the decrease of the velocity ratio in the domain near the conduit of warm water, but in the down reaches they tend to become high with the increase of the velocity ratio. The maximum values of the cross sectional areas within iso-concentration contours become large in proportion to the velocity ratio. The volumes within iso-concentration contours become large with the increase of the velocity ratio when the velocity ratio is small, but when the velocity ratio exceeds some value, the relation that the volumes within iso-concentration contours are proportional to the velocity ratio does not hold good. (3) The influences of Froude number The influences of Froude number did not appear remarkably in the abovementioned range of Froude number. In addition to the above results, the relation between the maximum temperature and the distance from the conduit of warm water, the relation between the temperature and the cross sectional area within iso-concentration contour, and the relation between the temperature and the volume within iso-concentration contour were obtained by modifying a little the equations derived from the analysis of a simple dispersion model of warm water.

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To make proper application of energy conservation techniques in designing air-conditioning systems, it is required to estimate the amounts of the effects of many energy conservation techniques in each phases of air-conditioning system. This estimation holds so much amounts of computation that it is impossible without making use of computer system. Moreover, to make use of this estimation as a tool of routine work in design process, it is necessary that the estimation method not only retains a sufficient accuracy but also terminates in a limited computer execution time. We, authors, studied a simplified method of thermal load calculation which constructs the first step of energy consumption analysis. In this method, first, we arranged weather data of year-round every days to a few days for a month by means of the multivariate analysis method. And then calculate year-round heating/cooling load by means of daily periodic stational rule by month. This paper reports about this simplified method and its verifications.

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This paper dealed with a subject of water hammer of closure in water supply piping system of builing and the authors analysed a application of the basic equation derived from theory and experimental values. Experiments were made about a practical straight piping and the characteristic of pressure waves were analysed. Then, it was found that the characteristics of closed gate as boundary condition were calculated by substituting the experimental values into the basic equations. So the authors could be ready to calculate the basic equations of water hammer. In addition to these, the authors dealed with the relations between a closed time and a maximum pressure rising rate by water hammer of a faucet.

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In the previous reports we calculated annual cooling and heating coil loads, power input to fans and fan loads of variable air volume (VAV) systems and studied on their energy savings. In this report, we measured suply air quantity, power input to fans, cooling coil loads and refrigeration load of VAV systems equipped in east and west zone of the existing building. The air-conditioned area of the east zone was 2543m^2 and that of the west was 2633m^2. The measured VAV systems were the typical ones which handled transmission loads with constant air volume and solar and interior loads with VAV. Each fan was controlled with inlet vane. The measures were performed in August and November. As a result, we confirmed that the measured values were nearly equal to the theoretically calculated suply air quantity, power input to fans and refrigeration load. As to energy savings of these systems, some results are shown as follows. (1) Compared with CAV system, the power input to the fans of VAV systems was about 61%. (2) In the measurement in August, the cooling load from outdoor air decreased to about 61% by employing air-to-air heat exchangers. (3) In the measurement in November, the weekly eleminated cooling coil loads were 442kcal/m^2 by using free cooling.

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