ESTGV - DEC - Artigo em revista científica, não indexada ao WoS/Scopus
Permanent URI for this collection
Browse
Browsing ESTGV - DEC - Artigo em revista científica, não indexada ao WoS/Scopus by Subject "Air permeability"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Air permeability measurements of dwellings and building components in PortugalPublication . Pinto, Manuel; Viegas, João; Freitas, VascoVentilation represents a significant part of heat loss in winter, leading to the need to minimize airflow. However, it is absolutely necessary to ensure indoor air quality and the safety of the users and to control the risk of condensation. Ventilation is responsible on average for 30%e40% of energy consumption in air conditioning in Western European buildings. There is great variability in air change rates (ACH [h 1]) from country to country and the minimum value takes into account comfort, sensory and hygrothermal criteria. In Portugal improvements have been made in the air permeability of window frames, but despite the improvements also made in installing mechanical extraction ventilation devices in kitchens and toilets, these often do not guarantee the minimum number of air change rates required. Air permeability tests were recently carried out in five flats with identical construction characteristics, in the same building, with the aim of characterizing the air permeability of buildings and components, in Portugal. These data are particularly useful for improving the design of building components (e.g., windows and roller shutter boxes) and to perform simulations with reliable data.
- The influence of ventilation systems on domestic gas appliances: an experimental studyPublication . Pinto, Manuel; Viegas, JoãoVentilation systems play an important role in the energy consumption of heating and cooling, defining hygrothermal conditions and air quality of dwellings. Among other functions, they are absolutely necessary to ensure oxygen levels needed for household combustion appliances. In Portugal in multifamily housing and with natural ventilation systems, installing a mechanical exhaust fan in every kitchen (decentralized ventilation) is common. In this paper, the impact of such a device is evaluated regarding the performance of a water heating appliance for heating the indoor environment or for domestic hot water (B-type gas appliance usually installed in the kitchen). The combination of natural or mechanical ventilation in the kitchen with the natural exhaust of the gas appliance’s combustion products were tested as well as the evaluation of critical conditions that lead to stopping the gas appliance safely or to reversing the combustion products in the respective exhaust duct. One of the main conclusions to be drawn is that in the case of mechanical exhaust in the kitchen simultaneously with the natural exhaust of the gas appliance’s combustion products, the kitchen’s exterior air inlet is a key device for ensuring proper exhaust of combustion products. In extreme situations, reduced air intake by other means or high extraction flows, they can prevent safely stopping the appliance or even reversing the flow of the combustion products. For this purpose, the maximum flow of mechanical exhaust should also be limited.