English

Results from testing of a simple model in a wind tunnel are used to validate two computational fluid dynamics mathematical models. The results show that only the Reynolds-stress model provides a reasonably accurate representation of the inlemal flow, and that both models fail to predict the flow at the opening of the model

Life-Cycle-Assessment (LCA) becomes more and more an important tool for industry to choose the adequate material or technique leading to an expected product quality from environmental point of view. As the environmental aspects are just one part of the decision making process, economical aspects have to be implemented as well. Sustainable construction is a major driving force of building and construction technology. The building sector uses extensive quantities of natural resources, raw materials and energy.

Occupant-controlled heating, ventilating and air conditioning (HVAC) systems allow inhabitants of open-plan spaces some degree of control over their immediate microclimate. Typically, cooled air is supplied at floor or desktop levels. The amount and direction of air flow is under occupant control. Productivity increases have been attributed to this form of control. This paper proposes a simplified model of the thermal environment created by an occupant-controlled HV AC system and the behavior of the occupants within it.

The cost of higher insulation measures in all new house types may be paid for by savings from smaller, simpler and more efficient heating systems. These houses are more comfortable to live in, as well as up to 50% cheaper to heat.

The paper describes a method to calculate the heat flow through a multiple layer wall in a natural climate. The thermal properties needed for the calculation are the thermal resistance and the heat capacity of each layer, and they are assumed to be independent of the temperature. The natural climate can be measured temperatures, either surface temperatures or temperatures of the surrounding air. The method is based on well-known equations for calculating the heat flow due to a sinusoidal temperature variation.

Since the mid 70's, the construction industry has made significant advances in energy conservation and improved indoor conditions. These improvements, however, are shadowed  by an increase in building envelope problems to include water penetration, condensation on and in roofs and exterior walls and cladding damages in many of our newer buildings; These problems have been attributed to uncontrolled air leakage.