English

Building simulations are used to investigate building performance and design the building systems optimally. In particular, the air exchange between zonesand with the environment has a pivotal role inmodernventilation system design. Nevertheless, the model of the airflow becomes difficult for the modeler, motivated by the complexity of the grid that has to be modeled. IDEAS, a Modelica library, includes components for thermal multi-zone models of buildings as well as models for heating, ventilation, air conditioning and other elements that interact in the same model.

Indoor environment quality has been researched extensively, with many countries adopting regulations to ensure that building occupants enjoy healthy working environments. In many small island developing states (SIDS), such as Mauritius, the population benefits from perfect weather conditions, but building design considerations often under-estimate the effects of outdoor weather conditions, heat and pollutant emission, illumination and noise, which worsen indoor environment.

Unintended airflow through building envelopes leads to an increased demand in heating and cooling energy. The most common way to measure air leakage of buildings is the blower door test, which quantifies the overall leakage rate of one room or a building. To reduce air leakage and associated energy loss in new and existing buildings, it is necessary to identify leak locations and prioritize sealing of more substantial leaks.

The occupants’ satisfaction with the indoor environmental quality (IEQ) of a building is a key factor to determine if the indoor climate can be considered as acceptable. Current standards, evaluating the IEQ, do not always guarantee sufficiently high occupant satisfaction levels, since these standards do not handle all satisfaction influencing parameters, such as, personal preferences or perceived control. Therefore, the assessment of occupant satisfaction with the IEQ remains an important issue.

This paper describes the ongoing development of a new tracer gas test (TGT) for total air change rates measurement. This new TGT, intended for use in large-scale IAQ assessments and based on constant tracer injection, employs an alternative tracer gas that is more adequate than the currently employed SF6 and perfluorocarbons and that can be co-captured and co-analyzed along with commonly assessed VOCs using a commercial passive IAQ sampler. Via literature study and lab testing, decane-D22 was found to be a suitable tracer substance.

Recently, understanding thermal comfort management enabled the scientific community to broaden its research towards smart device set-ups, in order to further reduce energy consumption and thermal comfort satisfaction. Thus, the need to minimize user interaction and implement prediction functions has arisen. In this work, the development of a smart thermostat is presented. The procedure is divided into three basic stages: calibration, development of energy saving and thermal comfort routines, and comparison with a conventional thermostat’s operation.

Cooling in high ambient temperature (HAT) countries is a major energy consumer. In Kuwait, 70% of the electricity generated is consumed on cooling residential and commercial buildings. Because of the extreme temperatures in the summer, which can reach 50℃, outdoor fresh air vents are closed because AC units are incapable of cooling air at such elevated temperatures. Consequently, this has significantly reduced indoor air quality (IAQ) in residential and commercial buildings for indoor occupants.

In future building regulations, building performance is going to be extended to global performance, including indoor air quality (IAQ). In the energy performance (EP) field, successive regulations pushed for a "performance-based" approach, based on an energy consumption requirement at the design stage. Nevertheless, ventilation regulations throughout the world are still mostly based on prescriptive approaches, setting airflows requirements.

Most existing office buildings are equipped with indoor environmental quality (IEQ) sensors that are connected to the Building Management System (BMS) and provide feedback to the heating, ventilation and air-conditioning (HVAC). Unfortunately, they are often installed in locations selected based on practical reasons rather than for reliable representation of IEQ at actual workplaces. This leads to a difference in the IEQ sensed by the BMS and the occupants, resulting in increased complaints and decreased occupant satisfaction.

Improving actual operation performance of room air conditioners (RAC) shows great importance in the indoor environment and building energy conversation. The installation height and supply air angle of the indoor unit of RAC directly affect thermal comfort and energy performance in heating conditions. In this paper, a combined simulation of building, indoor air distribution, and performance of RAC is proposed to investigate the influence of installation height and supply air angle. The combined simulation model was validated by experiment results.