Study on the Airflow Structure in Cross-Ventilated Rooms with the Full-Scale Model Experiment

Cross ventilation is one of the most important techniques for maintaining a comfortable indoorenvironment in hot and mild seasons with less cooling energy. But, at present, it is difficult to designindoor environment under cross ventilation because there is insufficient knowledge to evaluate theeffect of cross ventilation quantitatively. Thus the full-scale model experiment has been done in a large wind tunnel to examine the airflow property in the cross-ventilated space.

Study on Performance Evaluation of Mechanical Ventilation Systems for Occupied Houses

In the first phase of the current project, the ventilation rates of occupied houses in the northern region of Japan were investigated from 2001 to 2005. It was revealed that, despite installing mechanical ventilation system, low ventilation rate was found in many houses. The causes were believed attributing to lack of cleaning of grills, filters and insect protection meshes. The second phase of the project was to investigate the causes and resolve the problems. This project was started in 2005 and 12 houses installed with mechanical ventilation system were investigated.

Sizing of Room Air-Conditioners for Minimum Energy Consumption and Peak Power

Important oversizing factors are observed for room air-conditioners leading to important energy wastes and costly summer peak demands for utilities. This article intends to show that sizing decisions should be based on dynamic simulation results and include an assessment of the air conditioner part-load performance. The sizing methodology established is applied to evaluate different oversizing levels for different types of buildings, climates and systems. This enables to compare our methodology to typical rules of the thumbs applied in France.

Results of Monitoring a Naturally Ventilated and Passively Cooled Office Building in Frankfurt A.M., Germany

In this article the concept of a new energy-efficient office building and results of a 3-year monitoringare described. The monitoring was performed within the German funding programme ENOB.In this building most of the offices are naturally ventilated and passively cooled. Another focus of theenergy concept is on regenerative heating.Monitoring results show that the integrated planning enabled a very low consumption of energy forheating, ventilation, cooling and lighting.

RC Networks Approach for Hybrid Envelops in Positive Energy Building

This work lies within the concept of positive energy buildings. The aim is to develop an activemanagement of local free energy (solar, air and earth) inside the envelops by convection heat transfer and by the use of phase change materials (PCMs) in order to store or release heat when needed. A 1D RC network simulation tool has been developed for different standard fronts including a solar air collector and a double skin faade (south frontage), leading to the thermal simulation of a room with different configurations, with or without PCMs integration and for ventilated envelops.

Quality Assurance of Solar Ventilated Facade and Mixing Chamber of the Moravian Metropolitan Library

The objective of this paper is to present long time monitoring and post occupancy evaluation of theMoravian Metropolitan Library with the ventilated solar faade used for space heating and with mixing chamber for cooling with the forced ventilation. In consequences of new requirements from the EU Energy Performance of Building Directives 2002/91/EC and changing Czech building regulations is necessary support collective research effort on quality assurance and standardization on solar components and installations in buildings.

Prediction and Control of Temperature in Air-Conditioned Indoor Spaces Using Proper Orthogonal Decomposition

A method for controlling the temperature of the occupancy zone in a room equipped with a fan coil ispresented. The heterogeneity of the air velocity field and the temperature distribution is considered. As it leads to a system with a great number of differential equations, the Proper OrthogonalDecomposition is applied to build a low order model. Moreover, the value given by a sensor oftemperature enables the estimation of the temperature in the occupancy zone with a state estimator.The performances of the model are shown through the first results of simulation.

Potential of Natural Ventilation in a Tropical Climate

Sustainable architecture design for tropical climates requires the use of natural ventilation besideseveral strategies, as appropriated materials, site location, faade orientation, solar shading, etc. Theindoor thermal comfort and thermal performance of the building depends on the bioclimatic zonewhere is located. The new Brazilian Norm ABNT NBR 15220-3 has established bioclimatic zones and guidelines for low-income houses. Due to the lack or scarcity of meteorology wind data, certainregions as Amazon and Northeast coast were inserted in a same zone.

Occupancy Calculation for the Control of Mechanical Ventilation

Ventilation is essential for health and comfort of building occupants. It is particularly required to diluteand/or remove pollutants emitted by occupants metabolism. The concentration of metabolic CO2 iswell correlated to metabolic odor intensity. Therefore CO2 concentration can be efficiently chosen asan indoor air quality indicator when occupants are the main pollution source inside the buildings.

Multicriteria Characterization of Adaptive Comfort Variables in Office Buildings

Analytic models and static approaches as the case of Fanger, Deval, Sherman, Gagge, and Stolwijkmodels cannot completely predict indoor thermal comfort. Building designers could take advantage of adaptive approach of thermal comfort which can account for the complex interaction betweenoccupants and their environment that could affect their comfort.We had carried a field study in two office buildings on March 2005. It has included physicalmeasurements and questionnaires on thermal perception and appreciation.