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It is now known that the use of Building Information Modeling (BIM) procedures offers many benefits in the design and management of buildings. According to recent legislative enactments the BIM procedures will become mandatory for Public Works as from 2019. There are several advantages by using BIM procedures, among them the following can be highlighted: gaining a clear overview of the building plant system, evaluating the spatial coherence of the plant networks, the evaluation of the interferences to keep the system do not interfere with the functionality or the aesthetics of built environments. The present work analyzes the BIM procedures with particular reference to air conditioning systems in existing buildings, to their performance and management characteristics. The objective consists of analyzing the different BIM procedures and critically comparing the information provided by the IFC standard published by the European Institution Building SMART International, recognised as a standard by ISO, with the main reference standards for building installations and facilities design.

Building materials are usually characterized in stationary or almost-stationary conditions and mono dimensional heat flow regime. The existing standards (such as ISO 9869 or EN ISO 6946, EN 12664, EN 12667, ISO 8302 etc), require experiments carried out in steady-state conditions, with a very fine control of the measuring parameters with the aim to apply a simple and reproducible procedure for the determination of thermal properties. However, the thermodynamic conditions that lead to a steady-state operating mode and mono dimensional flow are very difficult to obtain (in real conditions) or very expensive and time consuming (in climate chambers). In this paper the authors present the development of a method for thermal characterization of building components, inferring the steady-state conditions, when only measures in transient conditions are available. The method, based on an adaptive linear neural network (ALNN) model also could be have the potentialities to determine the thermal diffusivity from a significant transient behavior ad hoc imposed. The study targets multilayered walls homogeneous and the results are compared with the experimental data measured by a climate chamber that operate according to the standard EN 12667

This study will assess the influence on the acoustic insulation of facade of small elements such as ventilation holes or mechanical ventilation systems. These elements are present to ensure an appropriate air exchange, and they can be with or without heat recovery units. The noise insulation of facade, taking into account such ventilation holes, was evaluated starting from the calculations carried in accordance with the procedures laid down by the standard EN 12354 and performing measurements concerning specific case studies.

This work proposes the application of a new simulation method based on fractal geometry for the calculation of the thermal conductivity for building materials. The results obtained are compared with the measurement, in a climatic chamber, of the heat flow through a material chosen as the sample. The test sample is made with “pietracantone”, a stone widely used as a building material and as an ornamental stone in the areas of Cagliari and Sassari in Sardinia. This material is characterized by a limestone matrix and a porosity which significantly influences the value of thermal conductivity. It is not known to the authors that this material had already been studied for its thermal properties.

In this study a theoretical analysis of a collector augmented by a bottom booster reflector is presented. An analytical model has been developed and used to estimate the solar irradiation passing through the transparent cover of a flat collector, both with and without a bottom reflector. The analytical model is based on the anisotropic sky model and takes into account a finite length system with different angular configurations and reciprocal shading and reflections between reflector and collector. Computer simulations have been carried out in order to find the optimum angles of the reflector with respect to the plane of the collector. Optimal inclinations of the collector and reflector for each month at 39° N latitude have been identified.

This paper deals with the problem to derive a marginal condition for the onset of spontaneous thermoacoustic oscillations of a gas in a circular tube, subject to a variable shape of the temperature gradient along the side wall, with one end rigidly closed and the other closed by a piezoelectric element converter. In this study the acoustic impedance of the piezo element is arbitrary in order to achieve marginal conditions between those exhibited with rigidly closed end, and those with end opened onto free atmosphere. Moreover, marginal condition is outlined adopting a variable shape of the temperature gradient with respect to the position of the stack along the tube. The marginal condition is provided at the same time with respect to variable piezo-impedance and variable position of the acoustic driver. The solution includes all dissipative effects related to the compressive and shear viscosity and the heat transmission in the boundary layer at the side wall and end wall. The formulation is given in the framework of the linear theory and the first order theory in the ratio of a boundary layer thickness to the tube radius.