English

Occupants control indoor environments to meet their individual needs for comfort. The control of window is the most common natural ventilation method influencing indoor environment as well as the energy use of the buildings to maintain a suitable environment. Therefore a better understanding of window control behaviour of the occupants has significant implication to enhance occupant comfort with minimal energy consumption. The objective of this study was to identify an appropriate algorithm and variables to develop a predictive model for window control.

Balanced ventilation units are well known to provide a sufficient amount of fresh air in residential buildings in a controlled way, without relying on ever-changing naturally driven forces. During colder periods, heat recovery ensures a reduction of the ventilation heating load. Outside the colder periods, recovery is reduced or shut off automatically, providing mechanical ventilative cooling. During warmer periods, the recovery is used again to provide a comfortably cool supply of fresh air.

Earlier field measurements in Low Energy Buildings have shown that excess temperatures can easily occur during summertime in well-insulated houses, also in northern part of Europe. If a ground source heat pump is used for heating and there is a bidirectional ventilation system, the borehole can be used for free cooling in summertime and the chilled air can be distributed by the ventilation system. In this study, a simulation of a single family nZEB located in the Swedish city Gothenburg was conducted.

This paper will present the context and application of earth tube systems for the provision of ventilative cooling and general make-up air in the heating, ventilation and air conditioning (HVAC) sector of the built environment; with a focus on case studies in Canada.  

Airborne bacteria-carrying particles (BCPs) in an operating room (OR) can cause post-operative infections in the patients. The ventilation system in the OR is crucial in removing or diluting airborne BCPs. This study numerically assessed a newly developed OR ventilation scheme – temperature-controlled airflow (TAF), with special focus on the influence of heat loads on the airflow and BCPs concentration. TAF supplies clean air at different temperature levels to different zones and establishes a high-momentum downward airflow pattern over the operating table.

Demand Control Ventilation strategy resilience is analysed through the envelope leakage distribution. Global building envelope leakage has great impact on energy consumption and targeted tightness values are systematically decreased in the several thermal regulations around the world. This leads to a more controlled ventilation system, but also to a more sensitive system to the leakage distribution. Considering fixed test cases with known entry data, two types of relative humidity based DCV strategy are analysed through their response to randomized envelope leakage distribution.

This paper presents a new concept of ventilation system for residential building, based on a hybrid ventilation system, mainly control by weather conditions and IAQ sensors to optimize exhaust airflows rates, for the purpose of improving global building energy performance and improving the quality of life of the occupiers.

Many studies reported that there were insufficient ventilation and excessive CO2 concentration in air-conditioned residential buildings, but few solutions were provided. This study first investigated the performance of three possible ventilation strategies of air-conditioned residential buildings, including overnight natural ventilation, short-term natural ventilation, and short-term mechanical ventilation.

The recent development of affordable and quite accurate temperature sensors and Indoor Air Quality (IAQ) sensors has led to a growing interest in continuous indoor climate monitoring. Not just amongst scientists and engineers but also amongst building owners, developers and e.g. architects interested in boosting our buildings’ health and comfort qualities.

By the end of 2020 all newly constructed buildings have to be nearly zero energy buildings (nZEB). In school and office buildings the ventilation system has a large contribution to the total energy use. A smart control strategy that adjusts the operation of the ventilation to the actual demand can significantly reduce this energy use. Consequently, control systems are becoming an important part of the ventilation system in these nZEB buildings.