This paper describes thermal analysis procedures of heat exchangers for air conditioning systems which are used as outside air cooling systems or heat recovery systems. The performance of heat exchangers can be evaluated by frictional pressure drops in the two fluids utilized and the amount of heat exchanged between those fluids. Moreover, the pressure drops and the exchanged heat can be evaluated as exergy. Therefore, in this paper, the performance of heat exchangers is measured by exergy. Exergy analyses are becoming more common in power generation plants, but little work has been done to analyze the performance of heat exchangers utilized in air conditioning systems. Air supplied from heat exchangers in air conditioners does not produce any power; it can only heat or cool room air. The concept of exergy is believed to be useful for evaluating power plants, but not for evaluating non-power plants. It is important to expand this concept, though supply air does not produce any power. It should be possible to measure it by exergy, since there is a temperature difference between the return air and the supply air. Conventional exergy analysis is presented in thermal engineering texts in general forms. For example, the exergy of a heat exchanger is calculated by performing an exergy flux analysis on the two fluids at each inlet and outlet. In the exergy analysis in this paper, some of the inlets and outlets (i.e. exhaust air) are omitted if they are not used. Thermal design procedures for air-to-air cross-counter flow heat exchangers are developed as an application of the exergy analysis. The design procedures are applied to a type of exchanger used in outside air cooling systems suitable for rooms containing high heat density equipment. The specified heat exchanger is similar to those commonly used in air conditioning systems. Empirical evidence has suggested that the new design procedures can provide acceptable designs without accounting the cost of heat exchangers.

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It is important to know a head loss of the flow in a concentric double pipe such as a reaction type flowmeter and a chemical reaction tube. The present study gives its experimental data using various types of concentric double pipes, in particular, giving the attention to the loss of total head through a turning-flow region from the outlet of the inner pipe to the inlet of the annulus between the inner and the outer pipes. They are given in terms of a non-dimensional clearance length (ξ=0.125〜50.0) between the outlet of the inner pipe and the bottom of the outer pipe for various values of area ratio (m=1.05〜∞) and Reynolds number (Re=4.2×10^3〜3.5×10^4). It is clarified that the effect of the clearance length upon the loss coefficient is classified into the three groups in proportion to the variation of m, namely, m≦1.54, 1.88≦m≦2.26 and m≧3.74 respectively.

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Numerical study has been done for comparing radiant heating system with warm air heating system which mainly focuses on the effectivity of radiation heat. First, authors could achieve some empirical index (i.e., so far called critical convective heat transfer coefficient, c.c.h.t.c.) by which the energy savings characteristics of the applied heating system may be evaluated for the space. However, in the first paper of this series, a theoretical formula has been presented for estimation of the c.c.h.t.c.. The conception used in the development of theoretical formula is that, when the thermal environmental conditions are considered constant and the changes of temperature in one of the surfaces (underchange surface) of space happens without causing any change in the heat loss of another exterior surface (object-surface), the convective heat transfer coefficient of that object-surface takes a particular value and has been called critical value. This c.c.h.t.c. as an index determines which heating system brings about less thermal load when used in a space under equivalent thermal environmental level. In the second paper of this series, effects of various physical and or environmental parameters have been numerically experienced upon the c.c.h.t.c. through Experimental Design Method, based on which the theoretical formula obtained for c.c.h.t.c. in the first paper has been affirmed. In this paper, energy savings border (i.e., line or plane) as a new term has been proposed, by which the space can be divided into two zones. Each zone implies either conventional warm air heating system or radiant heating system may produce more thermal load depending on the location of thermal environment conditions indicator (i.e., it may be body temperature of man, etc.). An approximate formula-by means of c.c.h.t.c.-has been developed for evaluating the energy savings border, besides, the validity of this approximate formula has been affirmed by collating it with that obtained from the concise method.

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It is not suitable to use the values of water demand based on one factor such as the using water volume per unit floor area or per unit person in building, for planning of water supply equipments. Because, the water demands are influenced by the various factors due to the properties of buildings. The purpose of this study is to introduce the equations to estimate the water demand in the various buildings. This paper describes on the office buildings as the Part 1 of which contents are given below. Based on the investigation of water uses in office buildings being conducted in the 9 major cities in Japan, we clarified the properties of building and equipment, the conditions of water demand and the water conservation and the opinions of persons in charge of building maintenance for water uses. We analysed these factors using the Quantity Theory Cluster III and clarified the relation between these item-categories. After analyzing these factors related to the water demand, we introduced multidimensional equations to estimate the water demand per unit floor area and per unit person in building using the multiple regression analysis.

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The purpose of this study is to introduce the equations to estimate the water demand in the various buildings. This paper describes on the hotels as the Part 2 of which contents are given below. We conducted the investigations of water uses in hotels in the major 9 cities of Japan in the same way as that of the Part 1. On these results, we clarified the properties of building and equipment, the conditions of water demand and the water conservation and the opinions of persons in charge of building maintenance for water uses. We analysed these factors using the Quantity Theory Cluster III and clarified the relation between these item-categories. After analyzing these factors related to the water demand, we introduced multidimensional equations to estimate the water demand per unit floor area, per unit employee and per unit person who can be accommodated in hotel using the multiple regression analysis.

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Various types of electrostatically argumented scrubbers have been investigated for fine particle emission control. This paper studies some of the basic mechanisms of collection of charged particles by packed column scrubbers. In Chap. 2, collection efficiencies are determined theoretically. First, the Reynolds number, which characterizes the flow field, and the three dimensionless numbers, which represent the effects of space charge, image force or interception respectively, are selected as dominant factors by rewriting the equation of particle motion in dimensionless form. Next, the approximate equations of the target efficiencies under the individual mechanism of space charge, image force or interception are derived through the numerical calculations of air flow paterns close to a packed obstacle in the range of Re<40, and finally, the approximate equation of the target efficiency under the condition that three effects work simultaneously is derived as a combination of the forgoing target efficiencies of each mechanism. In Chap. 3, the equipment and the method of the experiment to verify the propriety of the theory are described. The packed column is 1m long and 5cm square in cross-section. The packed materials are 34μm diameter steel fibers, 0.84% in packing density or 200μm diameter copper fibers, 13.6% in packing density. The test aerosol is atomized DOP particles, whose size distribution measured by cascade impactors is log-normal distribution of geometric mean diameter 1.45μm and geometric standard deviation 1.84, and whose charge density determined by collecting them on a filter paper and measuring the current to ground is about 0.05C/kg. The mass concentration and the charge density at the inlet and the outlet or some intermediate points in the column are measured to determine the penetration of the particle mass or the particle charge under various conditions. In Chap. 4, experimental results in the range of inlet loading 0.3〜2g/m^3, face velocity 0.3〜2m/s and column length 0.2〜1m are shown and compared with theoretical calculations. For the precipitation of charged particles due to the space charge effect in the empty column, the experimental results agree well with the theoretical calculations. For the filtration in the conventional packed column (namely, the filtration of uncharged particles), the target efficiency proposed by Friedlander for Re<1 is more suitable than theoretical one for experimental results in spite of the experimental conditions of high Reynolds numbers (1<Re<40). For the filtration of charged particles in the packed column, the target efficiency derived in Chap. 2, in which only the interception target efficiency is replaced by Friedlander's one, can explain the experimental results well, and the propriety of the theory is verified experimentally. In Chap. 5, the performance of the scrubbers is determined by theoretical calculations using the equation of the target efficiency derived above and the experimental equation of pressure drop proposed by Iinoya. The results show that the collection efficiencies increase with gas residence time or pressure drop. The comparison of the collection efficiencies in the operating conditions of same pressure drop and same gas residence time shows that; thin fiber packed materials are advantageous in high pressure drop and short gas residence time conditions; and that the fiber diameter dose not affect the sucrubber performance in low pressure drop or long gas residence time conditions.

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A thermally-blanced tank has more than one additional sub-header pipe connected to the main tank with several connecting pipes. Thermally stratified heat storage is achieved by selective input corresponding to the temperature profile in the main tank and the input water temperature. In this paper, a simulation program to predict the characteristics of the thermally-balanced type storage tank has been developed. This contains the concept of R-value model which was developed for mathematical estimation of a temperature-stratified type storage tank. The R-value model assumes that temperature distribution in the tank can be calculated in two regions, namely the perfect mixing region and one-dimensional diffusion region, and the R-value which is a ratio of depth of the perfect mixing region to the tank depth can be estimated by Ar-number (Ar_<in>) at the tank inlet. This paper first describes a mathematical model and studies acuracy of the model by compairing the calculated results with experimental ones which was shown in Part 1. The effect of the dimension of the sub-header pipes and the proportion of the tank on the performance is then examined by the simulation program. The characteristics of balanced type storage tank under stepwise input condition has also been examined using a new Ar-number (Ar_h), the representative length of which was the height of the tank (H) as the following Ar_h=Hg(Δρ/ρ_0)/u^2 Finally effectiveness of balanced type storage tank is described by comparing with the temperature-stratified type under several conditions.

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From the results of the previous report, it was found that the effect of orifices on pipe losses differs with the cases of L/D_0=1 and L/D_0≧2. Then, to obtain fundamental data on the uniform outflow from a perforated conduit or a slot, it is necessary to consider the two cases of L/D_0=1 and L/D_0≧2 separately. Therefore, this paper describes our experiments with four orifices drilled on lateral wall of pipe in the cases of L/D_0=1, 2, 3. Moreover, in the case of L/D_0=1 when five or six orifices are drilled in pipe it is experimentally tried to make clear how the number of orifices has an effect on stream. By means of measurement of the discharge volumes and pressure distributions, discharge volume rates and pipe losses were forecasted in the case of a perforated pipe.

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The interference of flow through multiple unihole orifice plates in series, which are typical of successive area contraction and expansion in a pipeline, was clarified in the preceding report. But another result will be obtained, when the location of a hole on the plate deviates from the center of plate or the number of holes are plural and/or relative position of holes on one plate is changed by revolution of another plate, which are also very impotant subjects. This study investigates the mutual interference of flow through twofold uni- and multihole plates. First, the characteristics of resistance of each multihole plate are examined. Then, the resistance of twofold multihole plates in series is investigated experimentally. The results are summarized as follows. 1) The resistance coefficient of the multihole plates is a function of only open area ratio and thickness ratio, similar to that for perforated plates. 2) Though the dependence of the interference coefficient of twofold multihole plates on spacing between two plates shows a different tendency according to hole numbers, it can be uniformly represented by non-dimensional spacing. 3) When the non-dimensional spacing is greater than about 5, the interference of twofold multihole plates almost disappears. 4) When the non-dimensional spacing is less than about 0.5, the interference coefficient I becomes to depend largely on turning angle. In particular, when calculated interference coefficient I_i is less than 1.5, I is proportional to I_i universally.

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Estimation of thermal storage load is the most imporant portion in design space load calculation for intermittent heating operation. In this paper, a simplified method of thermal storage load calculation is proposed, which is useful to heating system design. This method is to correct base storage load used by some factors related to building thermal characteristics. On the other hand, the effects of solar radiation have been rarely considered in heating design load calculation. We analize this effects and lead "Load due to directions" to the heating design load calculation.

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