Hybrid ventilation systems may consist of a combination of natural ventilation for air supply and a mechanical exhaust system. The quality level of thermal comfort is influenced by e.g. the way of air supply, the heating system at the facade and internal heat loads. This article deals with these parameters and their influence on the indoor climate based on research in climatic chambers.
By now hybrid ventilation systems are being used successfully in many projects. Three projects will be used to create a picture of the way in which the hybrid ventilation system has been used and of the experience with it. It can be concluded on the basis of these projects that hybrid ventilation is readily applicable and has a positive effect on comfort.
The paper presents examples of hybrid ventilation and control strategies in office and educational buildings from the IEA ECBCS Annex 35 HybVent case studies. The purpose is to extract the lessons learned in the case studies about the control strategy used. The conclusions are that in each building project the control strategy has to be carefully designed and operated, not only in relation to the general building design and the ventilation systems in the building, but also in relation to occupants habits, reactions and expectations to indoor climate and comfort.
This paper aims to identify major characteristics of hybrid ventilation systems, whereby a clear distinction is made between ventilation for Indoor Air Quality control and ventilation as part of a strategy for control of thermal comfort in summer. The aim is to identify the major differences between the various approaches and to develop some kind of rationale. Various building projects are used as illustration for the classification.
A hybrid ventilation system is a two-mode system that can automatically switch between passive and mechanical mode at different times of the day or seasons of the year. Some ventilation systems, including the hybrid system, have been set up in a full-scale test house constructed in Tohoku University, Japan to assess their performance. In this paper, the performance of each system is described by giving measurement results.
Update on the IEA ECBCS Annex 35 project on hybrid ventilation systems. Discusses hybrid ventilation air flow process, climate data and air flow around buildings, pressure distribution on building surfaces, air flow characteristics of openings, air flow characteristics for other elements, air flow in and between rooms in a building, and air flow process for whole systems.
Discusses the new concept of hybrid ventilation, and the objectives of IEA ECBCS Annex 35 research in this area. Important areas of research are the development of control strategies, theoretical and experimental studies, the development of a decision tool, the implementation and demonstration of hybrid ventilation, reporting and expected results.
Login