Loading...
Publication
Climatização de espaço através da utilização de jatos confluentes horizontais
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 4.61 MB | Adobe PDF |
Authors
Advisor(s)
Abstract(s)
O presente trabalho tem como objetivo principal o desenvolvimento de um sistema de ventilação com jatos confluentes horizontais que garante boas condições de conforto térmico e qualidade do ar num espaço ocupado. Os testes foram efetuados numa câmara experimental com paredes de 6 cm de espessura, com 2,7 m de comprimento, com 2,30 m largura e com um pé direito de 2,40 m. O sistema de ventilação foi construído com quatro ventiladores acoplados a quatro condutas verticais e com um extrator de ar fixado no teto ao centro da sala. As condutas estão localizadas no canto das paredes da sala equipadas com orifícios horizontais de saída dos jatos junto às referidas paredes.
Foram efetuados ensaios experimentais e ensaios numéricos. Nos ensaios experimentais foram utilizadas várias condutas para estudar a influência do diâmetro da conduta no perfil da velocidade do ar nos orifícios horizontais e também foram realizados ensaios de visualização com fumo e laser. Nos ensaios numéricos, utilizando uma câmara virtual equipada com 4 pessoas, uma mesa central, quatro cadeiras e um extrator, foram simuladas numericamente o escoamento para condições de verão e inverno, onde os dados de entrada foram obtidos experimentalmente.
Os estudos foram efetuados para as condições típicas de um dia de inverno e de verão com temperaturas do ar de entrada de 20ºC e 25ºC, respetivamente, com humidade relativa do ar de 50% para ambos os casos. Foram avaliados o escoamento interno, os níveis de conforto térmico e da qualidade do ar, o risco de resfriamento e o índice de distribuição do ar.
Pode-se concluir através dos resultados obtidos que o presente sistema de ventilação por jatos confluentes horizontal junto à parede garante boas condições de conforto térmico e de qualidade do ar, tanto no verão, como no inverno.
The present work has as main objective the development of a horizontal confluent jets ventilation system that will ensure good thermal comfort conditions and air quality in an occupied space. Tests were conducted in an experimental chamber with 6 cm wall thickness, 2,7 m long, 2,30 m wide and ceiling height of 2,40 m. The ventilation system was built with four fans, coupled to four vertical conductors, and with an air extractor fixed to the ceiling in the center of the room. The ducts were placed in each corner of the room with horizontal exit holes for the jets. Experimental and numerical tests were performed. In the first ones several ducts were used to study the influence of their diameter on the air velocity profile in the horizontal holes, and also visualization tests using smoke and laser lights. In numerical tests, using a virtual chamber occupied with four people, a central table, four chairs and an extractor, the flows for typical summer and winter conditions were simulated in which the input data were obtained experimentally. The studies were carried out for summer and winter typical day conditions with inlet air temperatures of 20 °C and 25 °C, respectively, with 50% relative humidity in both cases. The properties evaluated were internal flow, thermal comfort and air quality levels, cooling risk and air distribution index. It could be concluded from obtained results that horizontal confluent jets ventilation system placed near the wall guarantees good levels of thermal comfort and air quality, in both situations summer and winter
The present work has as main objective the development of a horizontal confluent jets ventilation system that will ensure good thermal comfort conditions and air quality in an occupied space. Tests were conducted in an experimental chamber with 6 cm wall thickness, 2,7 m long, 2,30 m wide and ceiling height of 2,40 m. The ventilation system was built with four fans, coupled to four vertical conductors, and with an air extractor fixed to the ceiling in the center of the room. The ducts were placed in each corner of the room with horizontal exit holes for the jets. Experimental and numerical tests were performed. In the first ones several ducts were used to study the influence of their diameter on the air velocity profile in the horizontal holes, and also visualization tests using smoke and laser lights. In numerical tests, using a virtual chamber occupied with four people, a central table, four chairs and an extractor, the flows for typical summer and winter conditions were simulated in which the input data were obtained experimentally. The studies were carried out for summer and winter typical day conditions with inlet air temperatures of 20 °C and 25 °C, respectively, with 50% relative humidity in both cases. The properties evaluated were internal flow, thermal comfort and air quality levels, cooling risk and air distribution index. It could be concluded from obtained results that horizontal confluent jets ventilation system placed near the wall guarantees good levels of thermal comfort and air quality, in both situations summer and winter
Description
Keywords
Jatos Confluentes Ventilação Conforto térmico Qualidade do ar