We studied the effect of condensation forms on the heat transfer characteristics of the two-phase closed thermosyphon. The condensation forms in the condenser section of two thermosyphons were filmwise condensation and dropwise condensation respectively. The experiment was carried out by operating them under the same experimental conditions. The heat transfer characteristics were investigated by changing the input temperature and flow rate of cooling water. As a result, the heat transfer rate in the case of dropwise condensation was larger than it in the case of filmwise condensation, the increasing rate of the heat transfer rate is about 40〜60%.

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This paper introduces models estimating adjusted energy baseline, which are used in actual Energy Service Company (ESCO) projects, and analyzes estimation accuracy of the models. First, the accuracy of the ESCO models that include several independent variables, for example outdoor air temperature, number of occupancies or operating equipments, and the accuracy of simple regression models whose independent variable is only outdoor air temperature, which are newly made by the authors, are compared in order to reveal how the independent variables except for outdoor air temperature affect the estimation accuracy. The results show that the accuracy can be improved about 4.3% by considering the independent variables besides outdoor air temperature Next, the accuracy of the ESCO models and the accuracy of the models made by the authors using equations proposed by ASHRAE, which can estimate the energy consumption in moderate season, are compared. The results show that some ASHRAE models can estimate energy consumption more accurately than ESCO models. Finally, the accuracy of a model whose coefficients are determined using daily energy consumption data and the accuracy of a model whose coefficients are determined using monthly energy consumption data are compared. The result shows for the purpose of estimating monthly energy consumption, the two models gave same estimation accuracy. Therefore for estimating the monthly energy consumption, it is enough to fit the coefficients using monthly data other than daily data.

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Sweat is important for the thermal response of human body in the thermal environment. It is dealt with as pure water when the influence of sweat on the human body temperature is studied in the prediction and evaluation of the thermal comfortability of the environment. However sweat is salt water with low concentration in reality. Not only does salt change the vapour pressure of the water, it may also affect the permeability of water in cloth because of the blocking of water movement by salt These influences of salt on the heat and moisture transfer in cloth can be considered to become unignorable when the salt accumulates in the cloth through several sweating and drying processes. The former part of this paper reports on experiments of pure or salt water uptake, using sodium chloride that is the main impurity of sweat. Experimental results show that salt water penetrates into the cloth at a lower speed than pure water. The latter part shows the model of absorption isotherm of cloth considering salt influences and gives some qualitative explanation for the result of experiments with the use of this model.

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An OCCSS (Open-Closed Cycle Switching System), which consists of two temporary storage tanks and two switches, forms an open circuit with a temporary storage tank and an open heat storage tank and a closed circuit with another one and heat loads side. Replacing temporary storage tanks each other by manipulating two switches, the system operates as the closed one without using any heat exchanger. A combination of the OCCSS with an open-type dynamic ice storage tank makes it possible to transport ice/water mixture to loads side in a closed circuit. In this paper, the method to store ice to the temporary storage tank and draw ice/water mixture from that using only water flow was proposed. In the storing process, the ice mass is formed in the temporary storage tank by supplying slush ice/water mixture and separating them by the difference of densities. In the drawing process, the ice mass rotated by a water wheel installed in the storage tank is smashed by the horizontal jet stream ejected from the top of the storage tank And then the ice/water mixture is drawn from the storage tank. The experiments to store slush ice to the ice storage tank were conducted by changing the flow rates and their entering IPFs. Also the experiments to measure the IPF of ice/water mixture drawn from the ice storage tank were conducted by changing the conditions of water wheel driving flow rates and upper ejecting flow rates. Electrical resistance methods were adopted to measure the IPF in the tube flow and total weights of ice stored to the ice storage tank and drawn from that were calculated. It was shown that storing and drawing processes proposed in this study were practical experimentally. Also, it was obtained that the conditions of high supplying flow rates and high entering IPF were preferable to store ice in high density. The relations between the IPF of ice/water mixture drawing from the ice storage tank and supplying flow conditions were obtained.

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