Paper 7
Evaluation of Local Thermal
Discomfort in a Classroom Equipped with Cross Flow Ventilation
Eusébio Z. E. Conceição1, Mª. Manuela J.
R. Lúcio2, Vitor D. S. R. Vicente1 and Vítor C. T.
Rosão1
1FCMA, Universidade do Algarve, Campus de
Gambelas, 8005-139 Faro, Portugal
2Vertical Grouping of Schools Professor Paula Nogueira, Rua da
Comunidade Lusíada, 8700-248 Olhão, Portugal
Abstract
This paper presents an evaluation of the local thermal discomfort level
in a classroom equipped with cross ventilation, for a typical moderate
summer day in Portugal. Three different ventilation configurations based
on window and door opening were considered. In each, the thermal comfort,
air quality and acoustical comfort conditions were also evaluated.
This experimental study was made in the South of Portugal, exposed to a
Mediterranean climate. Thermal comfort was based on the PMV index, the air
quality was based on the air renovation rate and acoustical comfort levels
were based on the reverberation time, voice clarity, definition and early
reflection ratio. The detailed local thermal discomfort analysis was based
on draught risk and uncomfortable air velocity fluctuations. Other
measurements included relative humidity, the radiative mean temperature,
carbon dioxide concentration (tracer gas decay), and noise level decay of
impulsive response. Results showed that for the warmest of weather open
windows and classroom door gave the best air quality and comfort
conditions.
Key words: natural ventilation, cooling, school, Mediterranean
climate, indoor air quality, comfort, acoustic conditions.
References
ANSI/ASHRAE Standard 62.1: (2004). "ASHRAE Standard - Ventilation
for Acceptable Indoor Air Quality". American Society of Heating,
Refrigerating and Air-Conditioning Engineers, Inc.
Conceição EZE and Lúcio, MMJR : (2006). " Air Quality inside
compartments of a school building: evaluation of air renovation rates and
carbon dioxide concentration. The International Journal of Ventilation. 5,
(2), pp259-270.
CR 1752: (1998). "Ventilation for buildings: design criteria for
the indoor environment". Comité Européen de Normalisation (CEN).
Brussels.
Decreto-Lei nº 129: (2001). "Regulamento dos Requisitos
Acústicos do Edifício (RRAE)". Diário da República. I Série- A,
N. 109. Mai 11th.
Decreto-Lei nº 79. (2006). "Regulamento dos Sistemas Energéticos
de Climatização em Edifícios (RSECE)". Diário da República. I
Série- A, N. 67. April 4th.
Fanger PO and Toftum J: (2002). "Extension of the PMV model to
non-air-conditioned buildings in warm climates". Energy and
Buildings. (34), pp533-536.
Fanger PO: (1970). "Thermal Comfort". Danish Technical Press.
Fanger P and Pedersen C: (1977). "Discomfort due to air velocities
in spaces". Institut International du Froid. Paris. France.
pp289-296.
Fanger,P, Melikov A, Hazawa H and Ring J: (1988). "Air turbulence
and sensation of draught". Energy and Buildings. 12, pp21-39.
Isbert AC: (1998). "Diseño acústico de espacios arquitectónicos"
Edicions UPC.
ISO 3382: (1997). "Acoustics - measurement of the reverberation
time of rooms with reference to other acoustical parameters",
International Standards Organisation.
Olesen BW : (1997). "International development of standards for
ventilation of buildings". ASHRAE Journal. April, pp31-39.
|
