Submitted by Maria.Kapsalaki on Fri, 10/25/2013 - 20:09
This paper discusses the potential of passive cooling techniques for Malaysian modern houses with the aim of reducing air-conditioning usage. A full-scale field experiment was carried out to reveal the detailed indoor thermal environment for various ventilation strategies. Night ventilation was found to be better than daytime ventilation, full-day ventilation and no ventilation in terms of air temperature reductions during the day and night. Night ventilation improves thermal comfort more than the other ventilation conditions based on operative temperature.
In a building, energy consumption and user’s comfort are directly related to its thermal performance. In early stages of building design, architects do not have enough input data to perform precise calculations. Anyway, due to the importance of the initia
Describes a study carried out to analyse the findings of VOC levels found in a tropical office building under different conditions of ventilation operation. Twelve target VOCs and TVOC were measured under two scenarios - normal occupancy and with the ventilation system shut down. Suggests evaluating the area-specific emission rates figures (SER) as the better method of determining source indicators.
During September 1998 to April 1999, environmental monitoring was carried out in part of the Djomi Museum, located in the warm humid tropics of Arnhem Land, Australia. An important finding of the study is that in this well sealed building with some thermal mass, internal RH under the influence of the air conditioning was generally higher, and more variable. Importantly for a repository building, in its relatively 'passive' mode the Djomi Museum experienced virtually no combination of conditions likely to lead to major problems with mould.
This paper presents the design of an urban, low-cost and progressive enlargement house following sustainable, bio-climatic and energy conservation criteria in a tropical and humid climate. This building design is based on results of experimental and numerical research on passive cooling systems and heat gain control mechanisms carried out by the authors. This house is intended to be a bio-climatic response to the housing need for low-income social groups. The individual integral comfort and his relation with the environment are the most important concern.
A computer model for predicting natural ventilation in buildings by solar chimney alone is presented. The simulations are based on the solution of the 3-D steady laminar conservation equations of mass, momentum and thermal energy with an appropriate set of boundary conditions. The equations are discretized using a finite difference formulation and solved by the Marker and Cell (MAC) scheme. Indoor airflow fields and temperature distributions are discussed with respect to human comfort at the living level, 1 m above floor.
Passive solar cooling for hot humid areas represents an important field for innovation, if we want to solve comfort needs in spaces (especially housing) designed to reduce economic, technical and health requirements. In urban areas or deep valleys and rain forests, which are common in most of the tropical equatorial countries, external breeze is not frequent and air speeds are too low to produce cooling, using a simple cross ventilation system. Since 1982 the author has developed new designs and constructions using passive solar techniques.
A study by the Australian Institute of Tropical Architecture was undertaken using the energy rating software BERS to determine the influence of using low absorptance paint on the thermal performance of uninsulated houses in the warm humid tropics of Australia. It was found that using such paints reduced the cooling energy load in airconditioned houses and the number of degree hours naturally ventilated houses were outside a preset comfort zone.
This paper presents the findings of two recent studies on the thermal preferences of householders in upland and coastal tropical environments. The aim of the studies was to investigate those behavioural factors that influence a householder's appreciation of an indoor environment. The studies involved 159 households in Kampala, Uganda, and 104 households in Surabaya, Indonesia. The studies indicated that householders made choices regarding their indoor environments based not on comfort sensation alone, but on "real-world factors".
The typical passive design suggested for residential buildings in tropical hothumid climates is a lightweight building with many openings on the north and south walls to allow continuous natural ventilation, shaded by wide overhangs. In reality most people no longer favour this design approach for several reasons: building durability, noise problems. privacy, and social status. The work presented in this paper challenges the typical design suggestions and shows other alternatives that are more suitable for this climatic region.