This research studies the performance of a fast calculation method of view factors using computer graphics (CG) technique. This method uses the perspective images made by the technology of CG in order to calculate view factors that are necessary in heat transfer problems. The process to illustrate the perspective images by CG corresponds to searching planes with numerical calculation method such as Monte Carlo method. This method enables programmers to take advantage of the refined algorithm to search surfaces automatically. Further, view factors can be calculated at high speed by using graphics hardware. It was found that the accuracy of this method using CG technique was within the acceptable limit. As a result, it was verified that this method has a possibility to become an effective tool for the analysis of heat transfer problems with heat radiation.

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It is important to prevent contamination risk in a clean room even if the door is opened or closed. To control pressure difference between rooms is usually applied for a clean room and it goes well when the door is closed. But if the door is opened, pressure difference could not be kept at the setting level, so air currents go back and forth and are mixed in the doorway. And another problem is occurred. After door is closed again, variation of room pressure is too high or too low, so the pressure difference would be sometimes reversed and an air current with dust is inhaled from an unexpected gap to the clean room. We suggest a new technique which switches control methods in response to door opening/closing, which is called hybrid pressure control. If the door is closed, presser control is applied. If the door is opened, air volume control is applied to form an air flow in the doorway from high pressure room to low pressure room. And if the door is opened widely, sufficient air flow in the doorway is formed to prevent dust from coming in the high pressure room. If the door is opened narrowly, the air flow in the doorway is kept slightly and the air volume is balanced in each room to make pressure variation smooth. We verified pressure and airborne particle concentration variation with opening-and-closing operation of the door. And also we verified the flow direction visualized by smoke and measured velocity in the doorway and germ variation near the door. Then we obtained good results that agree with our intention and could verify the validity of our hybrid pressure control.

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Experimental research on performance of the plate type condenser is presented in case of using the heat pump system. HFC134a is used as working fluid. The plate number of this plate type condenser is 28 plates and the total heat transfer area is 2.66m^2. Heat transfer coefficient of cold water side and condensation are obtained for the region of saturation in heat transfer area of the plate. The overall heat transfer coefficient of plate type condenser is about 2250〜3300(W/m^2K) when the velocity of the cold water is 0.18〜0.41m/s. The empirical correlation are proposed for predicting heat transfer coefficients of the average condensation and cold water side and composed with the result of the commercial plate the condenser.

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Time changes of air conditioning exhaust heats distribution in Osaka city were estimated by energy supplies both electricity and town gas for the purpose of clarifying the space-time characteristics of the air conditioning exhaust heat. Energy supplies both by electricity and town gas were divided into building uses and air conditioners use. According to comparison between methods by energy supplies both electricity and town gas and methods by basic units of energy consumption, sensible heat from the air conditioner which is estimated by energy supplies both electricity and town gas was extremely large in a commercial and amusement district at night. Then, a temperature rise in the city gave biggest influence for air conditioner's exhaust heat in the district which is investigated this report. A temperature rise of 1.5 to 6.0 degrees Celsius involves a sensible exhaust heat from air conditioners increase of 70 to 140W/m^2 in the commercial and amusement district.

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In order to improve the efficiency of a solar cell system, compaction (improvement of a light received density) of a solar cell module and directive (dependence characteristic of a solar position) reduction are tried. In this study, the optimum arrangement of the solar cell module with plant shoot shape is investigated. So, in this paper, relation between coptophyllus shoot shapes, such as a dogwood and a ginkgo tree, and a light received amount was clarified by numerical simulation, and the optimal solution of each shoot shape and the result of the light received density were obtained. Furthermore, the light received characteristic of each shoot when setting a size of a leaf, an installation location, length of a branch of a leaf, etc. as variables were investigated. It is predicted that a light received density increases from the result of analysis by distributing a solar cell module with a coptophyllus shoot shape compared with a square module.

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In this paper the emission rate of water vapor during cooking operations was examined because water vapor generated from cooking may cause dew condensation and influence indoor air quality in house kitchens and adjacent living rooms. Several typical dishes were selected from data base about home cooking of Japanese families. These dishes were classified by cooking method and heating time, and the emission rate of water vapor was measured with standard cooking methods. The results showed that the boiling type cooking generated water vapor at high rate and may raise humidity ratio in house kitchen. Then the elementary data of water vapor emission from a boiled pot was measured when important factors such as size of pan, heating power, water volume and with/without lid were changed. The obtained elementary data of water vapor emission can be expressed by simple equations. This paper demonstrated that water vapor emission from various cooking can be estimated by the elementary data when pan size, water volume, heating power and lid condition etc. were given.

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