Zühre Sü Gül

Investigations on sound energy decays and flows in a monumental mosque

This work investigates the sound energy decays and flows in the Süleymaniye Mosque in İstanbul. This is a single-space superstructure having multiple domes. The study searches for the non-exponential sound energy decay characteristics. The effect of different material surfaces and volumetric contributions are investigated using acoustic simulations and in situ acoustical measurements. Sound energy decay rates are estimated by Bayesian decay analysis. The measured data reveal double- or triple-slope energy decay profiles within the superstructure. To shed light on the mechanism of energy exchanges resulting in multi-slope decay, spatial sound energy distributions and energy flow vectors are studied by diffusion equation model (DEM) simulations. The resulting sound energy flow vector maps highlight the contribution of a sound-reflective central dome contrasted with an absorptive carpeted floor in providing delayed energy feedback. In contrast, no multi-slope energy decay pattern is observed in DEM simulations with a bare marble floor, which generates a much more diffuse sound field than in the real situation with a carpeted floor. The results demonstrate that energy fragmentation, in support of the non-exponential energy decay profile, is due to both the sound absorption characteristics of materials and to their distributions, as well as to relations between the subvolumes of the mosques interior.

Diffusion Equation-Based Finite Element Modeling of a Monumental Worship Space

In this work, a diffusion equation model (DEM) is applied to a room acoustics case for in-depth sound field analysis. Background of the theory, the governing and boundary equations specifically applicable to this study are presented. A three-dimensional geometric model of a monumental worship space is composed. The DEM is solved over this model in a finite element framework to obtain sound energy densities. The sound field within the monument is numerically assessed; spatial sound energy distributions and flow vector analysis are conducted through the time-dependent DEM solutions.

Acoustical design of Turkish Religious Affairs Mosque

The new Turkish Religious Affairs Mosque(DIB) with its prayer capacity and outstanding volume is the largest neo-classic mosque project of the past decade built in Ankara, Turkey. The Mosque is also one of unique examples of its scale for which the room acoustic design is applied in its design phase. Acoustical design of DIB Mosque is critical considering speech and music related activity patterns held in such religious spaces. Interior surface forms and materials of walls, floor, flat ceilings and dome are studied simultaneously with the architectural design as early as in the concept phase. Impedance tube is used for testing alternative materials for specifying sound absorption characteristics of reliefs and perforations. Computer simulation is applied as an acoustical design tool and estimations are held by ODEON v.11.23. Objective acoustical parameters including reverberation time, speech transmission index and A-weighted sound levels are assessed with and without sound reinforcement systems for fully...

Investigations on multi-slope energy decay formation within single-space monumental structures by diffusion equation modeling and intensity probe measurements

Multiple domed superstructures with different volumetric and material attributes are previously investigated using in-situ acoustical measurements and acoustical simulation methods for analyzing their contributions to multi-slope energy decay formation. Relevant acoustical parameters including decay rates and decay times are computed by applying the Bayesian decay analysis. Initial results indicate double- or triple-slope decay characteristics for specific measurement configurations for selected cases. The ongoing research is aimed at explaining the probable reasons of multiple decay formation as observed in such single space enclosures. Diffusion equation modeling (DEM) and intensity probe measurements are utilized to observe spatial sound energy distributions and energy flow vectors. Both computed and measured flow vectors indicate the contribution of central dome to the later energy feedback. For a specific case the trial by DEM over virtual model with floor with marble instead of carpet resulted in a ...

Acoustic adventures over continents, among cultures: Under tides of academia and profession

After obtaining a Bachelor of Architecture and an MFA with an emphasis in amphitheater acoustics, I was accepted into Rensselaer Polytechnic Institute’s unique Graduate Program in Architectural Acoustics. There I completed an MS degree focusing on architectural acoustics in coupled spaces and was honored to receive the Robert Newman Award, a TCAA Student Paper Award and an ASA commendation for student design. Since 2006 I have applied my academic focus to design projects, first at RBDG Inc. in Dallas, and later at home in Turkey at MEZZO Studyo, the firm I co-founded in 2009. Turkish governmental supports have afforded MEZZO the opportunity to become a critically recognized “R&D incubator.” We’ve also completed over one hundred design projects, both in-house and teamed with architectural-engineering groups around the world and are proud members of NCAC (National Council of Acoustical Consultants). During the restricted times of not managing my firm—and my 3-year-old son!—I enjoy giving university lectures...

Investigations on acoustical coupling within single-space monumental structures using a diffusion equation model

Sound energy distributions and flows within single-space rooms can be exploited to understand the occurrence of multi-slope decays. In this work, a real-size monumental worship space is selected for investigations of non-exponential sound energy decays. Previous field tests in this single-space venue indicate multi-slope formation within such a large volume and the multiple-dome upper structure layout. In order to illuminate/reveal the probable reasons of non-exponential sound energy decays within such an architectural venue, sound energy distributions and energy flows are investigated. Due to its computational efficiency and advantages in spatial energy density and flow vector analysis, a diffusion equation model (DEM) is applied for modeling sound field of the monumental worship space. Preliminary studies indicate good agreement for overall energy decay time estimations among experimental field and DEM results. The energy flow vector and energy distribution analysis indicate the upper central dome-struc...

Acoustical considerations in design and construction of Turkish Contractors Association headquarters

A LEED candidate building of Turkish Contractors Association Headquarters is a prestige building located in Ankara, the project and construction of which is sponsored by leading contractor companies of Turkey. As it represents the status of Turkish construction industry, from concept phase to the very recent inauguration of the building, the major consideration has been the application of latest technology and concepts such as sustainability within the scheme of building that can pioneer future works in the field. Chilled beam ventilation is one example of new technologies applied in the building system design that takes into account high energy efficiency with minimum use of fuel or natural sources. In acoustical terms, the building envelope and structural members together with interior and environmental noise sources in relation to the building services are studied. In order to provide acoustical comfort levels in acoustically sensitive spaces and to control noise and vibration at the source and sound p...

Multiple-slope sound energy decay investigations in single space enclosures with specific geometrical and material attributes

Acoustical coupling until now has basically been studied to define the peculiar sound field within acoustically coupled enclosures in which multiple-slope energy decays can often be observed. The key concern of this study is to reveal the potential of multiple-slope energy decay formation in over-size single space structures with particular geometry and distribution of materials in different acoustical performance characteristics. Specifically, multiple dome superstructures, composed of one central dome supported by semi-domes and transitional elements, are selected for the case studies. The interpretation of the acquired data is carried in order to broaden the definition of “the coupled volume system” with an emphasis on invisible sources and apertures of acoustical coupling in a “single volume system.” The methodology of the research involves joint use of in-situ acoustical measurements, acoustical modeling/simulation methods, and computational analyses. Bayesian analysis approach is applied in quantify...