control

The absolute necessity of air renewal to maintain indoor air quality and thermal comfort in buildingsfaces the major issue of energy consumption reduction and optimisation in building sector. Manystudies carried out so far point out the performances improved thanks to the recourse to ventilationstrategies and control algorithms in the aim of optimising the energy consumption of air renewal, butvery few of them could assess the performances in the particular case of large buildings despite thepotential energy gains it represents considering the great volume and huge air flow rates induced.

Evidence suggests that a significant number of large highly-glazed spaces have major design flaws that lead to energy wastage and discomfort. Provision to control solar gains are generally insufficient in these buildings, which can lead to excessively high temperatures during the summer. Besides, the solutions implemented to overcome these issues usually have a high energy cost, whereas passive techniques may well limit these problems. This paper deals with design issues related to solar protections.

When designing natural ventilation for complex buildings, it is key to understand whether there is a unique solution for the flow, or if multiple flow regimes are possible. Here, we show that in a 2 storey open plan office type building, in which the floors are connected to a common atrium, two stable flow regimes may occur under identical conditions.

This paper analyses an individual control system that accounts for human thermal adaptation.Although the conventional individual control system has been shown to provide a satisfactory level of thermal comfort, there are questions over its energy efficiency. It has therefore become urgent to develop a new individual control system that can ensure both energy saving and thermal comfort. In this study, the alleviation time is proposed as an energy-saving control strategy for the individual control system.

Achievement of thermal comfort can be improved if individual control of the environment is allowed,namely through a local heating system (LHS), consisting of individually controlled radiant heating panels, adapted to a common office desk to a seated person. The coupling with of a new radiative module enhances the simulating capabilities of an existing CFD numerical model. The added improvements are applied to the evaluation of the thermal performance o the LHS. A comparative analysis clearly demonstrates the relevance of a due consideration of radiative exchanges.

Subjective experiments with a non-isothermal task conditioning system were conducted toinvestigate impacts of the system on thermal comfort and productivity in a climate chamber of Kanto-Gakuin University, Japan. All subjects participated in "default condition test: 26C / 50% RH" at first.Then a half of the same subjects participated in "standard condition test: 26C / 50% RH", and theremainder subjects participated in "task-ambient test: 30C / 50% RH + TAC", just one week later again separately. Thermal, humidity, comfort sensations, and other psychological factors were investigated.

This paper presents the main results of a research on an individually controlled office environment. The research was carried out in a laboratory that counts on an air conditioning system with underfloor air supply and individual airflow control devices for personalized thermal comfort. The evaluation was based on quantitative and qualitative data acquired respectively by means of comfort variables local measurements and people participation. The main results refer to the thermal comfort parameters proper to the referred environment and parameters for the system operation.

The second part of the VIP Indoor air pollutants concerns the sources of pollutants and effective measures to control them or to make their impact on occupants less severe.

The author describes the most important indoor air related health determinants and a table gives information on the source characterisation of health determinants indoors, their control method along with examples of actions that could be taken by national level bodies or societies.

Local control of ventilation in large buildings is considered to be a main issue in energy savings regarding the huge energy losses that are usually induced by such large volumes. An efficient ventilation system and the development of local control ventilation strategies could prevent large buildings from having an unsuited or overvalued ventilation and reduce significantly the energy consumption.