CIFICEN   24414
CENTRO DE INVESTIGACIONES EN FISICA E INGENIERIA DEL CENTRO DE LA PROVINCIA DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Natural ventilation in a room with a front window, an internal heat source and a top or bottom rear vents
Autor/es:
PERALTA, EDGAR D.; CASTILLO, JOSÉ A.; TOVAR, RAMON; HUELSZ, GUADALUPE; THOMAS, LUIS P; MARINO, BEATRIZ M
Reunión:
Simposio; SIERyS Third International Symposium on Renewable Energy and Sustainability; 2015
Resumen:
Opening windows is a habitual way to ventilate buildings to decrease their temperature and remove pollutants. Different regimes can be developed according the location and size of windows, doors and internal heat sources. Here we study the fluxes generated employing a front window and rear vents. Results from temperature measurements and schlieren images taken on a 1:20 scale laboratory model are presented. Water is used as working fluid, maintaining dynamical similarity with a full-scale room, while an electric heater represents an internal heat source. The number and level of the vents are varied, and the average temperature inside the room is compared with that of the front window case. When the heater is turned on and only the front window is opened, a bidirectional flow is developed throughout it where warm fluid exits through the top half while cool ambient fluid enters through the bottom half, developing a transient mixing type ventilation. A steady temperature is reached when the exiting thermal plume transports the energy produced by the internal source. When a rear top vent is opened in combination with the front window, an exit flow is developed through the vent maintaining a bidirectional flow through the window, increasing the incoming flow and reducing the exiting one. In this case mixing-displacement ventilation is reached. As the number of the top vents and the exiting net flow through them increase, the bidirectional flow through the window becomes an incoming unidirectional one, hence the ventilation regime in the room becomes a displacement one. In this case the minimum average temperature inside the room is reached. When rear bottom vents and the front window are opened, the flow in the room also becomes a displacement one, but in this case the window operates as exit for the fluid and the vents as entrance.