In recent years, global environmental problems have been getting more serious and the importance of the measures toward the problems is being recognized all over the world. Especially, global warming is the most important issue of the world's leading industrialized nations, and it has been discussed over and over again at the Kyoto Protocol, Toyako Summit, COP15, and so on. Around 30% of the annual energy consumption in homes in Japan depends on heating equipment. Therefore it is expected that it has a high possibility of energy saving. On the other hand, the recent remarkable technological development has improved Japanese people's life style and air-conditioning equipments such as floor heating and air-conditioners have become indispensable for our lives. To pursue energy-saving performance and to achieve the performance of comfort are extremely important in the future design. The goal of this study is an establishment of thermal comfortable performance assessment in the heating room of the residence. To achieve this goal, the comfortable performance calculation technique considering the local thermal comfort was developed, and the heating energy consumption on the humanly thermal comfort was grasped by an actual measurement and CFD analysis. The 1st report is about the result of an accuracy of CFD calculation in a room with the heating floor and air conditioning. Then, the grasp of the amount of heating energy consumption based on the humanly thermal comfort and deliberation the heat transmission property characteristic in the wall surface were made. An experiment and analysis of a living room of a wooden house which complies with the new energy saving standard of the forth area were made. The specifications of the living room are about 20m3 floor spaces, room about 50m3 in volumes, heat loss coefficient about 3.2W/m2. The room was heated by the floor heating and the air conditioning, and an actual measurement and the CFD analysis (steady state) was conducted. As a result, a comparison of CFD and experiment were made in the respect of wall surface temperature, air temperature, top and bottom temperature distribution, and heat balance. I could confirm that the result of CFD almost accorded with one of the experiment both in a floor heater and air conditioner.

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This paper proposes a building thermal simulation method that can integrate zones with HVAC equipment and that is developed for a building energy simulation tool, the BEST. In the proposed method, zone air temperature and humidity are simulated by switching two solution methods. During conditioning hours, the equations of zone heat balance that is affected by HVAC equipment as well as adjacent zones are solved by the explicit method at short time intervals. After conditioning hours, the solution method is switched with the implicit method and the heat balance equations are solved at relatively long time intervals. The implicit method can be also used for thermal load simulations. Runge-Kutta Method is used as the explicit method and Backward Euler method is used as the implicit method. The proper time intervals according to the solution methods are examined. 5-minute is the practically reasonable time interval for the explicit method. On the other hand, short time intervals are not necessary except for the rapid change of turbulence for the implicit method. A calculation method of the convective heat from wall surfaces at variable time intervals is also presented.

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There are several methods for energy saving in buildings. The installation of energy recovery ventilator is one of the effective solutions to reduce ventilation load, e.g. energy consumption of air conditioner. Manufactures of energy recovery ventilator specify the performance and effectiveness of developed ventilator, and release the specification. However, there are few measured examples concerning actual buildings installing heat recovery ventilator in the view point of air conditioning load and reduction effect of the air conditioning power consumption. Against this background, this paper describes the outline of measurement survey of energy consumption reduction of air conditioning by energy recovery ventilators. As the measurement target, 1st floor of a two-storey office building, located in Gifu prefecture, a mild climate region in Japan was selected. There are seven heat pump air conditioning systems and four duct type ventilation systems with energy recovery ventilator units in that floor. From the measurement results, use of energy recovery ventilator confirmed to reduce air conditioning systems' energy consumption by approximately 30% in winter season.

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Since the growing of agricultural crop are directly affected by outdoor climate conditions, The large scale green houses are usually adopted to control the indoor climate conditions in the realm of agriculture. In general, the envelope of green house consists of polychlorobiphenyl and greenhouse effect is expected in it. In winter season, a supplementary heating device in vinyl house is needed because of the decrease of outdoor temperature and non-uniform distribution of indoor temperature. The previous research concerning indoor environment of green house are not enough and the precise numerical prediction of airflow and temperature distribution in large scale vinyl house are important to develop the effective design method in the viewpoint of energy saving. This paper reports two topics. The first is the field measurement of temperature distribution in large scale green house and the measurements were carried out in winter season to provide the validation data of numerical prediction. The second topic is numerical prediction corresponding to the field measurement and the results of numerical simulation were in reasonable agreement with the results of filed measurement. Furthermore, the effect of introduction of stirred fan that mixing air in green house are evaluated to analyze ventilation effectiveness and contribution ratio of each fan. In the view point to energy saving, the coupled numerical analysis of CFD and air conditioning system were carried out and the sensor position in green house and operational status of stirred fan had much impact to energy consumption.

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