PR2007

The purpose of this case study is to analyze stack effect problems and to develop the method minimizing stack effect in the tall complex building in the winter season. The main problems in tall complex building occur in high-rise elevators. Such problems in the elevator doors that do not close or exhaust air flows result in excessive pressure difference across elevator doors due to stack effect. Under the expected conditions causing the pressure difference, computer simulations with CONTAMW computer program and field measurement were performed in tall complex building.

Indoor Air Quality and thermal climate in schools is problematicin many countries. The status quo in the Netherlandsis presented (e.g. average CO2 levels in schools, problems with ventilation). The goal of a first study was to evaluate the performance of exhaust-only ventilation systems. In a following study, 6 schools with different ventilation systems were studied. Main conclusions from these studies were: IAQ in the evaluated schools did not meet the requirements and more ventilation was essential for better IAQ.

To predict ventilation and related air flow parameters, a lot of calculation techniques could be utilized; however the main difficulties concern ease of use and the providingof input data. Today, many advances are taking place, especially in the areas of user friendly access and embedded databases. To find reliable result in designingprocess and evaluate the performance of ventilation simulating methods are increasingly needed in every step of designing. They are especially important for making preliminary evaluations of complex ventilation and air flow strategies.

Results of survey on residential active cooling as the diffusion rate of air conditioner in five principal cities of in Japan, and those associated “human temperature sensitivity” for passive and low energy cooling are described. Increase in air-condition

The ENPER-EXIST project was initiated and coordinated by Centre Scientifique et Technique du Bâtiment (CSTB) within the framework of the Intelligent Energy Europe (IEE) programme. ENPER-EXIST involved partners from seven countries (Belgium, Denmark, Franc

Optimal indoor air quality, thermal comfort and energy conservation in schools is of great importance. A new development in indoor climate control in schools is hydronicradiant heating and cooling (HRHC). This system uses building mass to heat and cool the building. Water filled pipes are embedded in the core of the concrete slab. Water near comfort temperature is used. Slow accumulationof concrete results in small adaptation possibilities in order to meet the needs of users.

Due to the lack of national building regulation regardingthe energy requirements of Directive 2002/91/EC (EPBD) in Greece, Southern countries (Italy, Spain and Portugal) have been selected as index reference because of the similar climatic conditions and location in order to report the stage of Directives implementation (energyperformance calculations and energy rating procedures)for a future enforcement in Greece.Regarding the increasing energy demand in the island of Crete, this paper aims at the estimation of energy saving in buildings for the island of Crete.

For the assessment of air to air heat recovery systems in ventilation systems, efficiency seems to be the major evaluation parameter, although other parameters such as pressure drop, frost behavior and power consumption of fans can play an important role. Efficiency of a heat exchanger can be expressed in many forms; temperature efficiency, moisture efficiency, enthalpy efficiency, primary energy rate, etc. When speaking of temperature efficiency, an important difference should be made between the efficiencies at the supply and exhaust sides respectively.

The objective of this paper is to evaluate the usefulness and the accuracy of an artificial neural network (ANN) as a prediction tool of the wind pressure coefficient (Cp). The ANN is applied to predict the Cp for rectangularbuildings. The Cp values obtained by wind tunnel experiments are approximated by using a Cascade-CorrelationLearning Network model to make a prediction, and the performance of three kinds of residential ventilationsystems depending on the wind effect is evaluatedby using both of the predicted Cp and the Cp experimentallyobtained.

Multi zone computer simulation is used to predict the concentrations of carbon dioxide, carbon monoxide, formaldehyde and water vapour in a flat and detached house, fitted with five different ventilation systems all of which comply with current building regulations for England and Wales. Results show that, understandably, the different ventilation systems produce different spatial and temporal pollutant concentrations. A method based on equivalent ventilation rates for each pollutant is used to optimise the specification of the ventilation systems.