Solar radiation induced convection occurs quite often in glazed spaces. In spite of that the impact of solar radiation to airflow inside rooms and buildings is not usually taken into account when airflow patterns are studied. However, there are many cases when this impact cannot be neglected. The paper deals with the CFD modeling of airflow and temperature fields inside a glazed attic, and comparison of results with experimentally obtained data. The main goal is to find optimal locations of ventilation system inlets in order to increase the efficiency of solar energy utilization.
Most photovoltaic (PV) facades are built as curtain facades in front of thermally insulated buildings with air ducts in between. This causes additional costs for support structure and installation, while heat dissipation from the solar cells is often not optimal. Measurements carried out are facing both concerns: Integration of a thermal insulating layer (which meets the latest German heat preserving regulation WSV 95) into the PV facade plus additional cooling by active ventilation or water flow.
This paper discusses the first full version of IDEA-l, a new natural-lighting design tool for the early stages of the architectural design process. This computer program, which is part of the larger IDEA+ research project, allows the user to judge the impact of natural light on his architectural design. For this purpose a number of tests are provided, covering different aspects of natural lighting. This paper will discuss each of the tests and the involved algorithms.
This paper presents the multiple-view performance assessment of an existing office building undertaken with an integrated application. It includes the assessment of the energy consumption, room acoustics, occupant comfort, and the environmental impacts (fuel, materials, transport, and processes) . The simulation results have been compared with in- situ measurements monitored in the building during the post-occupancy phase to analyse the conformity of the results.
The present work deals with the determination of a mathematical correlation for conductivity in the fully water-saturated state in terms of dry-basis conductivity and porosity. In the mathematical model, the material microstructure is taken into account in a multiscale percolation system and the macroscopical conductivity is obtained with a renormalization technique. The model is presented and the obtained correlation is tested for some porous building materials . To conclude, we show how porosity can affect thermal conductivity.
Advances in psychoacoustics through the years, have made it possible to evaluate the acoustical quality of a room, based on several numerical parameters that have been developed. Even though there is not a total agreement about which parameters are truly important, some of them are accepted by most of the acousticians. When designing a concert hall, ray-tracing softwares can be used to calculate some of these parameters. However,some input data carry some uncertainties.
We give an overview of how windows are modeled in the EnergyPlus whole-building energy simulation program. Important features include layer-by-layer input of custom glazing, ability to accept spectral or spectral-averaged glass optical properties, incidence angle-dependent solar and visible transmission and reflection, iterative heat balance solution to determine glass surface temperatures, calculation of frame and divider heat transfer, and modeling of movable interior or exterior shading devices with user-specified controls. Example results of EnergyPlus window calculations are shown.
The important variation of the urban morphology has direct effects on the disparity of the outdoor climates, as well as indoor climates. In this context, this work aims at answering at the following question : how to simulate, in an operational way, the relation between urban form and climate, at an intermediate scale corresponding to the neighbourhood ? Our approach tries to answer to this question,1by working at the neighbourhood scale, and by proposing a complete and operational system of morphological indicators of the built environment.
This paper describes the development and validation of a simulation model for Advanced Integrated Mechanical Systems (AIMS) destined for residential applications. AIMS are defined as mechanical systems that integrate the functions of residential space heating (optional cooling), heat recovery ventilation and hot water heating. Efficiency advancements of these systems are expected through the use of intelligent controls, high efficiency fans and motors,and the use of computer models to optimize the performance. The model was developed as a stand-alone application for testing and validation.