Submitted by Maria.Kapsalaki on Tue, 01/14/2025 - 11:37
Buildings account for a substantial portion of global energy consumption, and heating, ventilation and air conditioning (HVAC) systems are responsible for approximately 40% of the buildings’ energy consumption. A building façade, with HVAC, has a great influence on the internal environment. An optimization of the façade design and operation can help improve building energy efficiency.
Submitted by Maria.Kapsalaki on Mon, 01/13/2025 - 15:23
Ensuring acceptable indoor air quality (IAQ) is critical for managing built environments. This is done by ventilating spaces with outdoor air to keep indoor pollutants like CO2, humidity, particulate matter, and VOCs within healthy levels. The effectiveness of ventilation strategies depends on factors like occupancy, pollutant types, and air terminal devices, which can be influenced by outdoor air quality, especially in urban areas with particulate matter and NOx. Ventilation devices can operate with constant airflow or adjust based on occupancy.
Submitted by Maria.Kapsalaki on Wed, 10/28/2015 - 16:51
House dust contamination has recently become an important issue in the residential indoor environment. This study evaluated ventilation systems for removing house dust efficiently in a full-scale residential room. Experiments and simulations were performed to investigate diffusion and deposition of house dust by different ventilation systems. Riboflavin particles were used as the house dust. Two kinds of ventilation systems were considered, namely ceiling exhaust and slit exhaust.
Submitted by Maria.Kapsalaki on Thu, 10/31/2013 - 21:25
The thrust of airtightness specification and testing is derived from energy considerations. The application to healthcare buildings and specialist laboratory facilities embodies the same principles but derives the appropriateness of the criteria with reference to [a] producing controlled and controllable cascading pressure zones and [b] specifying or quantifying the potential exposure in the event of failure of mechanical ventilation.
ASHRAE Standard 62.2P is being proposed to address residential ventilation issues. As housing, especially new housing, gets more airtight and better insulated, it has become clear that many homes are under-ventilated. The Standard contains requirements that provide minimum ventilation rates and source control measures necessary for acceptable indoor air quality. This paper uses previously reported analytical techniques to compare the energy costs of various ventilation strategies for a wide variety of climates and housing types.
The deposition rates of particles in a town-house with a forced air circulation and in-duct filters have been calculated for that study. It appears that the use of central forced-air fan along with in-duct filters allows the reduction of particle concentration. And it is more effective than reducing ventilation by closing windows or making homes more insulated.
How to avoid or reduce the influence of suddenly released contaminant when emergency occurs ? A 3D Full scale room with displacement and mixing ventilation system is numerically studied assuming contaminant released at certain positions in the room. IACS is adopted as an index that can be applied to determine ventilation strategy with the aim of defending indoor environment against contamination.
Investigations in six car parks were carried out. Measurements of carbon monoxide levels were made during the peak hours to compare the performance of the different types of ventilation systems : the performance is better with a combined supply and exhaust system than the exhaust only system though more energy is consumed.
In that study, induced ventilation is experimentally explored in a small well-insulated manufactured home, located in the northern edge of the Negev desert in Israel. Temperature monitoring was performed inside and outside the building in summer along with velocity measurements inside the building. The results show that with induced ventilation the air temperature inside the home is like the ambient temperature, whereas, when no openings, the temperature inside the manufactured home is higher than the ambient.