Kyosuke Hiyama

Thermal Performance Evaluation of a Dynamic Insulation Technology Applied to a Timber Framework House in a Real Environment

Abstract This paper presents the thermal performance evaluation of a dynamic insulation technology applied to the building envelope of a timber framework house. The concept of dynamic insulation technologies is to draw outside air in through insulation materials in a wall to recover conduction heat loss from inside the building. The authors applied dynamic insulation technology to the walls and ceiling of a timber framework house to allow outside air to pass through permeable insulation materials within the walls and ceiling. The experiment was conducted at a building in Sapporo, Hokkaido to evaluate the thermal performance of a building envelope with dynamic insulation technology in a real environment. The results showed that the dynamic insulation technology can significantly reduce heat loss through the building envelope.

Study on Statistical Prediction and Design Method for Indoor Thermal Environment

The indoor thermal environment is affected by many heat factors such as occupants′ activities and outdoor climate changes. Because each of them varies asynchronously, the heat factors′ variation shows a nonsingle degree of freedom overall. Moreover, the heat factors′ impact on space is not uniform. Therefore, there always exist spatial distributions and temporal variations. In practice, the number of degrees of freedom of an air-conditioning system is usually limited and less than that of the object zone. The control performance of an air-conditioning system designed under a perfect mixing method cannot be satisfactory because the spatial distribution is neglected. For energy conservation and thermal comfort improvement, it is necessary to propose an air-conditioning system design method which can positively use the spatial distribution and temporal variation of the indoor thermal environment. In this study, methods for indoor temperature fluctuation analysis and optimization of air-conditioner sensor location are proposed. To represent the temperature field structure, an index called CRI is integrated. With this method, the spatial distribution and temporal variation can be calculated immediately and analyzed statistically; furthermore, the indoor temperature and outdoor climate′s correlation can be concisely visualized. A case study is conducted to verify the validity of this method.