The hygrothermal behavior of a building component exposed to weather is an important aspect of the overall performance of a building. Today the hygric transport phenomena through a building envelope are well understood and a realistic assessment of all relevant effects can be carried out by one of the numerous models and computer programs, that have been developed in different countries over the last years. The calculation of the hygrothermal performance of a part of the envelope is state-of-the-art, but until now, the total behaviour of the actual whole building is not accounted for.

Air supply diffusers used in air-conditioning systems can be classified as ceiling diffusers, sidewall diffusers, floor diffusers, jet nozzles, and low velocity displacement diffusers. Fixed or adjustable slats are usually used to control airflow directions.

With the advancement of technology, and with the widespread availability of simulation tools, we are forced to consider which simulation tool would be appropriate for a particular problem. The seemingly trivial decision is in reality not very easy to make. And this leads to the practice of using the most sophisticated tool available for every problem. The levels of resolution and complexity are directly related to the accuracy of the simulation and to the total cost of the simulation process. A simple tool may be cheaper, but there is a high risk of inaccuracy.

The Norwegian Building Research Institute (NBI) has completed a study of the performance of balanced residential ventilation systems with heat recovery (HRVs) in Norway. The study involved both a national questionnaire survey and thorough laboratory tests of 10 HRVs on the market. The overall conclusion is that balanced ventilation with heat recovery provides very good air quality, and has a payback time of 4~6 years for the most profitable systems despite Norways cheap hydropower (0.09 /kWh in 2002).

This paper will address the shortcomings of typical heat balance-based HVAC design and analysis software when applied to thermal displacement ventilation (TDV) system design. The performance characteristics of thermal displacement systems that lead to inaccurate calculations from heat balancebased programs are discussed. Finally, the paper presents an approach for estimating the performance of TDV systems using existing heat-based calculation tools that responds to most of the significant differences between overhead mixing systems and thermal displacement systems.

During the last 20 years, the humidity sensitive ventilation system evolved to products increasingly simplified thus standardised. At Aereco, there were 5 generations of extract units, each modification of product was due to a change in the acceptation criteria. In many countries, systems with variable airflows are accepted and recognised ; regulations moved. In other countries, the orthodoxy of the constant airflow of an air change per hour remains in force for simplifying reasons or by ignorance of the real interest.

This paper presents the development of a simulation tool based on the Matlab computational environment for building temperature performance analysis with automatic control. The simulation tool contains mathematical models for buildings, HVAC (Heating, Ventilation and Air Conditioning) systems, sensors, weather data and control algorithms. The building mathematical model is described in terms of statespace variables, with a lumped approach for the room air governing equations energy and mass balances. In this context, the simulation tool structure and components are explained.

This paper describes a performance-based evolution model using Genetic Algorith as the evolution algorithm and CFD as the evaluation mechanism. The advantages of such an evolutionary performance-based design approach is that diverse instances of the state space can be investigated in relation to specific goal requirements that will enhance the possibility of discovering a variety of potential solutions. The model allows the user to explore and visualize the design evolution and its form generation in an attempt to stimulate the designer creativity that might contribute to their output.

A comfortable indoor climate environment is necessary for modern buildings and therefore the Heating, Ventilation and Air-Conditioning (HVAC) systems are widely used. Faults or disturbances are normally unavoidable in the systems and they will lead to more energy consumption or degradation of comfort level of indoor climate. Energy consumption is useful to detect the

Occupant responsive optimal control is developed for so called smart façade systems. The control optimizes the performance of the system by rotating a motorized louver slat in the cavity and ventilation dampers at the top and bottom of exterior and interi