English

The purpose of this study is to figure out the characteristics of thermal environment in a workshop at school in Japan and to propose the improvement method of the thermal environment without air-conditioning systems. In this paper, measurement results of thermal environment in the workshop and calculation results of vertical temperature gradient are shown. In the measurement results, indoor air temperature became very high in summer. Solar radiation was the main factor raising the temperature of PC roof, and large vertical temperature gradient was formed.

In recent years school buildings, containing the workshop in high school, are old in Japan. Therefore most of them need renovating. Any air-conditioning systems are not often installed in the workshops. Workshops without air-conditioning systems often have bad indoor thermal environments. Since bad thermal environment is exhausting and likely to cause some accidents, eco-renovation method for improvement of thermal environment is required. In this paper, various kinds of eco-renovation methods are examined by CFD simulation.

Because the super high-rise complex building would be designed vertically with a mixed-use space, a large amount of unpurified domestic sewage could be discharged continuously outside the building site. The waste heat from the sewage water can be used for low temperature heating and high temperature cooling sources for HVAC system such as radiant heating and cooling system, and domestic hot water services. This study aims to evaluate the availability of treated sewage water as an unused energy source in a super high-rise complex building.

Recently, a lot of multiple packaged unit system is adopted in small to medium sized buildings in Japan. This system enables to control each packaged air conditioner (PAC) individually because multiple packaged units are placed decentrally. However, it is not clarified sufficiently how indoor environment is formed when PAC is working. This paper shows the measurement results of indoor thermal environment in a medium sized building with PAC in all season for the purpose of clarifying the current status of indoor environment and its issue.

Recently, buildings with thermal energy storage system have increased because of its economic advantage. In thermal energy storage system using introduced outdoor air, building masses are used as thermal storage media and cooled by outdoor air introduced by a mechanical fan in night-time. In spring and autumn, the cooled building masses can work to reduce cooling load in day-time. In this study, the stored heat was calculated by using simple heat transfer models for various building masses, and the energy performance of this system was evaluated quantitatively by system simulation.

In this study, the concept of the Hybrid air-conditioning system utilizing convection and radiation heat exchange will be suggested. In this paper, the heat removal characteristics of Hybrid air-conditioning system will be described by theoretical review and experimental methods. Also the ratio of cooling load removed by Hybrid air-conditioning system could be divided as radiation and convection heat exchanges. The methods could be used to system design of Hybrid air-conditioning system.

This study tested the feasibility of employing artificial neural network (ANN)-based predictive and adaptive control logics to improve thermal comfort and energy efficiency through a decrease in over- and under-shooting of control variables. Three control logics were developed: (1) conventional temperature/humidity control logic, (2) ANN-based temperature/humidity control logic, and (3) ANN-based Predicted Mean Vote (PMV) control logic.

Wall heating systems are more preferable heating systems than other conventional systems due to their low temperature operating ranges. These systems are equipped with heating serpentines or panels where the water is circulated and the serpentines are mounted on the walls of rooms. Ground source heat pump systems are todays one of the useful renewable energy based heating systems.

Tracer gas measurements are an unparalleled means of measuring air recirculation, leakage, and air flow rates in air handling systems [1-5]. However, such measurements are subject to significant measurement uncertainty in field conditions. A common problem is imperfect mixing of tracer gas.

This study proposes the hybrid ventilation system and its design methods for high-rise buildings. The proposed hybrid ventilation system uses natural driving power for ventilation based on air flow in the whole building and indoor and outdoor pressure distributions. Furthermore, it solves the troubles of the conventional natural or mechanical ventilation systems. This paper presents theories and a process for duct design for natural ventilation which forms the basis of a hybrid ventilation system in high-rise buildings.