Search

Assessment methods to assess smart ventilation, in most countries focus only on comfort as criteria for the indoor air quality (IAQ) (Guyot et al., 2019). This is an issue as in doing so, pollutants that are known to cause harm to the human health are not taken into consideration while the exposure to VOCs will be elevated if the smart ventilation system lowers the ventilation flowrates to save energy (De Jonge & Laverge, 2021). This research addresses the question of what the impact of changing family sizes would be on the individual exposure to unhealthy pollutants for a smart ventilation system that only uses comfort related parameters to control the ventilation system. By introducing sources of Volatile Organic Compounds (VOCs) into a Modelica building energy and IAQ model of a typical Belgian apartment the occupant-dependent (CO 2 and RH) smart ventilation can be assessed for non-occupant dependent pollutants (VOCs). For three given smart ventilation systems, ten different households, with varying sizes and occupants are simulated. The results show that the presence of other family members influences the exposure to VOCs of an individual. One of the three smart ventilation systems is analyzed in detail, for this system, the minimum DALY count is 14.75 yr and maximum is 17.72 yr. They also show that the energy use of the building can be quite different although the only changing parameter in the simulation are the occupants. For the different simulated households, the minimum yearly energy use is 731kwh and maximum yearly energy use is 1319kwh. Similar results are obtained for the other two cases. Overall, the three smart ventilation systems show significant energy savings compared to the continuous nominal reference system but the expected impact on health increases. When designing a simulation-based assessment framework for residential ventilation, the occupant's behavior will always be an unknown factor to consider. The results indicate that in developing a simulations-based assessment framework, it is recommended to not assume just one household as in doing so, the system performance is not properly checked with regards to health and energy use during the lifetime of the system and the related expected variation in household types and sizes. The results in this paper confirm that a stochastic approach for assessing residential smart ventilation systems based on health-related pollutants (VOCs) should be investigated further. [ABSTRACT FROM AUTHOR]

This paper investigates experimentally the cooling performance of a concept, where the radiant ceiling is suspended from the hollow-core concrete slab and by ventilation supply in the plenum and the perforations of the ceiling tiles, ventilation air is distributed without ducts and air terminals to the occupied zone. Literature has proven that this concept allows for more streamlined installation procedures and excellent performance in terms of thermal comfort and draught. The paper reports experimental results from a climate chamber, where the concept was tested under both steady-state and quasi-steady conditions. The steady-state conditions were chosen to map the cooling performance with different air change rates, and different ventilation and water supply temperatures. The results showed that for air change rates of 3 h−1 in the occupied zone and water supply temperature of 17 °C, the cooling output from the ceiling increased by 10 %. The concept was also tested under quasi-steady conditions in a 48 h cycle to quantify the thermal buffering effect of the exposed upper concrete slab when subjected to ventilation supply air. The effect amounted to 11–12 % increased cooling capacity at the end of the working day when the driving temperatures between air, water and thermal zones were at their maximum. [ABSTRACT FROM AUTHOR]