The potential for error when using computational fluid dynamics (CFD) for investigating internal building airflows continues to be a critical issue in building simulation analysis. This topic is assessed in the current paper by examining the ability of a proprietary CFD code to simulate buoyancy and forced airflow regimes, typical of a naturally ventilated building. This issue is motivated by an ongoing research project, aimed at examining the relationship between external microclimate and internal building comfort, where CFD constitutes a major analytical tool.
The objective of this study is to evaluate the potential of two inertial ventilation techniques (buried pipes and thermal phase-shifting) for passive cooling of buildings in Brazilian climates. Using EnergyPlus, a typical residential building was simulated in two locations (Sao Paulo and Florianopolis). Simulations consider 5 alternatives of passive cooling, combining different scenarios of controlled direct ventilation, buried pipes and thermal phase-shifting. Results show the potential of these techniques in freefloating as well as in air-conditioning mode.
The issue of this paper is to present theoretical results for a solar chimney with thermal mass, where the glass surface is replaced by photovoltaic (PV) modules. A portion of the heat absorbed by the PV modules is dissipated to the air channel in convective form, and it exchanges radiation heat with the concrete wall. These cooling phenomena for the PV modules improve their efficiency with a lower working temperature. Both phenomena are heating process to the air and the concrete wall, that produce natural ventilation. The solar chimney is supposed to be isolated from any building.
A number of studies have examined the potential of using natural ventilation as a passive cooling system and comfort under warm conditions. Tanabe and Karma (1994) conducted an experimental work at 50% RH under different level of air speed. They found preferred speed at 28C to be 1.0 m/s, at 29.6 C, 1.2 m/s and at 31.3C, 1.6 m/s. Although traditional architecture of Iran has a very good background in terms of passive building design strategies for achieving comfort condition, however, they are mostly ignored and people are concerned with the rising costs of electricity and fuel.
Raising the solar reflectance of a roof from a typical value of 0.1–0.2 to an achievable 0.6 can reduce cooling-energy use in buildings by more than 20%. Cool roofs also reduce ambient outside air temperature, thus further decreasing the need for air cond
The approach of the building as a system in Time and its interrelationships with the environment, are presented as a “Matrix of Environmental Value (Ev)” that takes into account all possible aspects of “harmfulness – friendliness” towards the environment,
London’s urban heat island increases the mean air temperature which affects the demand for heating and cooling buildings. The simultaneous hourly air temperature in London has been measured continuously for a year. These data have shown that central areas
This paper presents an energy status study of a modern office building in the region of Xanthi. The results of the study are analyzed and evaluated with the use of appropriate software. Finally solutions are proposed for building’s energy rehabilitation.
This paper presents an analysis of some overlooked aspects in an environmental agenda for retail design. The work outline the analysis of the possibilities of maintaining low temperatures in an open-air markets stall space by using an appropriate shed and shading techniques and therefore avoiding direct solar radiation. Temperature difference of up to 100K was realised between shaded and un-shaded surfaces when some spot measurements were taken in the summer month of July (Ernest, 2004).
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