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The paper presents a study on the thermal behavior of a solar greenhouse set against one apartment of a residential eco-sustainable building in a temperate climate. Particular attention was given to the analysis of the contribution of solar radiation in winter heating in relation to natural ventilation. This study makes use of a transient energy simulation system named ESP-r (Environmentals System Performance - research).

An isothermal CFD study was made of a building perpendicular to the wind direction. The building was modelled with a closed façade, and consecutively with one and multiple openings. The sensitivity was investigated for different turbulence models, meshes and near wall treatments, both in 2D and 3D. A large sensitivity was found to the modelling options with regard to the predicted wind pressure coefficients (Cp) distribution, but less with regard to the predicted flow rate through the openings.

Recently, the hybrid air-conditioning system that used natural ventilation together with a mechanical air-conditioning was proposed. Hybrid air conditioning system is expected to be saving energy and maintain keep indoor thermal environment comfort.

This study analyzed the effect of intermittent operation of ventilation system on changes of indoor air pollutants' levels through field measurements. The changes of indoor air pollutants' levels, such as, CO2, PM10, TVOCs, and HCHO were monitored during 24 hours at each ventilation condition. One group was the operation time: 2 hours, 8hours, and 24 hours. The other group was the changes of start time of ventilation, before noon, after noon, and night, while the ventilation was operated only two hours.

This research, based on Computational Fluid Dynamics (CFD) analysis, focuses on the wind characteristics and the ventilation performance in the consecutive street canyons produced by various building complex configurations. In this research, the buildings in the street canyon space were distributed in either staggered or normal arrangements and, in consideration of the varying distribution and height of different buildings, high-rise buildings, middle-rise buildings and low-rise buildings were all included.

The calculation system for vertical ventilation with wind chimney on the roof driven by wind and buoyancy is presented and the necessary data is measured. The calculation system is based on the “pressure – airflow rate relationship (Pressure -Volume curve: P-V curve)” and the local velocity and static pressure at the point of chimney top. The P-V curves were measured by wind tunnel test for some typical shapes of wind chimney top. It is turned out that the effect of upper wind velocity can be eliminated by normalization of the pressure at chimney neck and airflow rate through the chimney.

In this study, we propose a method for forecasting heat emission effect in a small single-sided slit opening. In order to make a heat flux forecasting model, we carried out field measurement, wind tunnel experiment, and CFD analysis. In the field measurement, we measured heat flux and grasped the relationship of heat flux of the opening and airflow around the building surface. In the wind tunnel experiment, we measured airflow around the opening and grasped turbulence characteristics.

The main thrust of this paper is to investigate the optimized supply air condition and energy saving potentials of a dedicated outdoor air system (DOAS) applied to a high-rise apartment building. For a typical 132-m2 apartment unit, it was assumed that two different systems, namely, a centralized DOAS integrated with ceiling radiant cooling panel (CRCP) and a decentralized energy recovery ventilator (ERV) operated with packaged air conditioner, were installed.

In this research, a heat pump system with a heat source network is suggested which utilizes outdoor air heat, solar heat and ground heat as heat source for cooling, heating, hot water and refrigerating. This paper describes the summary of the suggested system and the results of the annual energy simulation. The heating and cooling loads, the electric consumption and the COP were calculated by TRNSYS 16 and evaluated in the cases of different local conditions and different system compositions.

In the previous study, a numerical method which simulates combined heat and moisture transfer process in solid desiccant materials was investigated. The calculation results successfully reproduced the cyclic process of the moisture adsorption and desorption. The validity of the numerical simulation method for the desiccant wheel was examined by the comparison between the experiment and the numerical simulation of the desiccant dehumidifier.