cooling

We describe the potential of using hygroscopic materials that release moisture and latent heat in order to reduce the temperature of building envelopes and, there upon, conduction cooling loads. It is analysed 3 different weathers and a classic Brazilian wall with different values of paint permeance on both external and internal surfaces. The results are presented in terms of temperature, moisture content profiles and heat fluxes, showing how to save energy from the natural movement of moisture.

The results of numerical simulation on the effects of solar chimney for ventilation in the new building of Faculty of International Environmental Engineering Kitakyushu University, Japan are described. The air velocity and pressure within the solar chimney were estimated by simplified methods and CFD calculation and both results agreed quite well. It was found that the air flow rates would depend on the inside wall temperatures and section ratio of solar chimney with the same section area.

This paper describes a thermal comfort survey of people living in courtyard housing. The study took place in the Iranian city of Ilam, which experiences a hot, dry climate. The survey compared the thermal comfort conditions of people outside using the courtyard housing, and was conducting during the hot summer season. Over 570 subjects responded to thermal comfort questionnaires. At the same time physical measurements were taken of such parameters as dry bulb air temperature, relative humidity and air velocity.

This paper examines the conditions of a relatively large courtyard (45 by 10 meters), enclosed by a one-story building, located in the Negev Lowlands. The region is characterised by hot, dry summer days, and wide temperature and relative humidity fluctuations. The courtyard was monitored under extreme conditions typical of the hot spells, common during transition periods, during which even night minima are sometimes well above the comfort zone.

The paper traces the paradigm changes for house design in warm-humid climates, from the preference for traditional elevated, lightweight, ventilated buildings, through the advocacy for heavy construction, to the present conclusion that both can be equally good. The extension of selection criteria is suggested, to include psychological factors, which seem to favour the lightweight, cross-ventilated buildings. The success of these depends on the cooling effect of air movement, hence an attempt is made to quantify this effect.

Passive Downdraught Cooling is a technique which will potentially become a substitute for conventional air-conditioning in Southern Europe and the hot dry regions of the world. As well as providing substantial energy savings, the technique avoids the need for ductwork, fans and suspended ceilings, and reduces the need for refrigerant based cooling. However, this approach has architectural implications which extends the vocabulary of 'passive design'.

Examines the difficulties of ensuring occupant comfort in challenging climates and less developed areas of the world such as the Galapagos. Temperatures can reach 30 deg C, but rarely go lower than 18 deg C, so no heating is needed. Describes the offices of the Galapagos National Park Service, built largely with low thermal mass and no insulation. Air conditioning and air movement depend on a filter-down effect from a single office.

States that when used with ice storage systems, cold air distribution systems are popular since they require less operating and capital costs. Stresses the importance of a consideration of occupant comfort. The study looked at air circulation and temperature distribution in a room, considering different orientation, velocities and sizes of jet for a given vertical location of air inlet and outlet on opposing walls. A control volume method was used to solve the Navier-Stokes equations and an energy equation in two dimensional rectangular Cartesian coordinates.

In Switzerland, even if the average daily temperature rarely exceeds 25º C during the summer months, more and more cooling plants are being installed in administrative buildings. The CUEPE participated as experts in some realisations that showed (simulat

Looks at two residential flats in a high-rise residential building in Hong Kong using HBT2 detailed building heat transfer simulation software. It analyses the influence of the thermal insulation layer in the outside walls on the yearly cooling load and maximum cooling demand. Tall residential buildings in Hong Kong do not usually incorporate thermal insulation. The simulation predicted a maximum decrease in annual cooling load of up to 6.8%, using a 5 cm thick thermal insulation coating which faced into the flat.