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An efficiency of the nonsingular meshless method (MLM) was analyzed in an acoustic indoor problem. The solution was assumed in the form of the series of radial bases functions (RBFs). Three representative kinds of RBF were chosen: the Hardy's multiquadratic, inverse multiquadratic, Duchon's functions. The room acoustic field with uniform, impedance walls was considered. To achieve the goal, relationships among physical parameters of the problem and parameters of the approximate solution were first found. Physical parameters constitute the sound absorption coefficient of the boundary and the frequency of acoustic vibrations. In turn, parameters of the solution are the kind of RBFs, the number of elements in the series of the solution and the number and distribution of influence points. Next, it was shown that the approximate acoustic field can be calculated using MLM with a priori error assumed. All approximate results, averaged over representative rectangular section of the room, were calculated and then compared to the corresponding accurate results. This way, it was proved that the MLM, based on RBFs, is efficient method in description of acoustic boundary problems with impedance boundary conditions and in all acoustic frequencies. [ABSTRACT FROM AUTHOR]

The constant search in the teaching and learning of undergraduate courses in architecture and urbanism has become recurrent in classroom practices. Having seen that it is of fundamental importance that this method brings the student when there is effective participation of the group. With this, the study of acoustics in architecture brings great benefits to the student's curriculum. It is believed that the establishment of principles and parameters based on the theoretical contents that take into account the interrelations between the physical and constructed space, contributes tangentially to the construction of spaces appropriate to the activities of man from the point of view of their audiovisual and environmental health. Experiences made with students of the architecture and urbanism course, such as practical classroom activities, theoretical post-class, have been largely relevant to detect student performance in the field of acoustics. In classrooms, when there is presence of other sources of noise, in addition to the speaker's speech and parallel conversations of students, it is important to requalify this environment, in the form of conjugating with the objective of satisfying with the experiences of the acoustic comfort for the social practices of man. This analysis of deficiencies and conflicts about built environments, especially classrooms, is necessary in order to study a form of noise reduction and how to treat the environment. Based on these concepts inherent to the built environment, the present work highlights the importance of well-designed school areas to noise control and the presence of constructive techniques, as a way of integrating the quality of audibility into the classroom, in particular, assuring a scenario pleasant, where the medium supposedly interacts with the man. [ABSTRACT FROM AUTHOR]

Thermally activated building systems have the potential to achieve significant energy savings, yet, the exposed concrete may also create acoustical challenges due to the high reflectivity of the hard surface. Free-hanging acoustical clouds reduce the acoustical issues, but also the cooling capacity of a radiant chilled ceiling system. Fan-induced air movement can be used to compensate for the cooling capacity reduction. We experimentally assess the combined effect of acoustical clouds and fans on the cooling capacity for an office room. We installed a ceiling fan between the clouds (blowing in the upward or downward direction) and small fans above the clouds (blowing horizontally) at the ceiling level to increase the convective heat transfer along the cooled ceiling. We tested the different fan configurations against a reference case with no elevated air movement. The tests conducted without fans showed that cooling capacity decreased, but only by 11%, when acoustical cloud coverage was increased to 47%, representing acceptable sound absorption. The ceiling fan increased cooling capacity by up to 22% when blowing upward and up to 12% when blowing downward compared to the reference case over the different cloud coverage ratios. For the variants with small fans, cooling capacity increases with coverage, up to a maximum increase of 26%. This experiment proves that combining fans with acoustical absorbents close to the radiant surface increases cooling capacity while simultaneously providing improved acoustical quality, and quantifies the impact. [ABSTRACT FROM AUTHOR]

In this study, acoustical performance of Mimar Kemaleddin Hall in Gazi University, Rectorate Building has been analyzed. The acoustic analysis of the hall has been performed by using a simulation program called ECOTECT v.5.20 and the results were developed by means of statistical reverberation times and geometrical acoustic analysis. The existing base model of the Hall was modified by using acoustic panels and various finishing materials. By comparing the results of 7 modified models, suggestions were developed depends on main function of hall for speech or for music. [ABSTRACT FROM AUTHOR]