G. Rosi, L. Teresi, A. DiCarlo, and F. dell'Isola
LaMS - Università degli Studi Roma Tre, Roma, Italy
Università degli Studi di Roma "La Sapienza", Roma, Italy
Liquid crystals - as all liquids - are generally modelled as incompressible media. In fact, mass-density changes occurring in these mesophases are minuscule and inconsequential in most regimes of interest. However, liquid crystals exhibit also phenomena that call for a more refined theory. In particular, it is experimentally well established that the Fréedericksz transition - i.e., the sudden ...
ÅF, Stockholm, Sweden
In this paper a pre-study on using COMSOL Multiphysics for rotordynamic analysis is presented. It is concluded that it is possible to use COMSOL Multiphysics to perform rotordynamical analysis. However, there are no standard environment for rotordynamics, hence the user has to extend the structural model with the rotordynamics effect such as gyroscopic effect and rotordynamical coefficients. By ...
University of the West of Scotland, Paisley, Renfrewshire, UK
The Jecklin Disk is a sound absorbing disk placed between two omnidirectional microphones. It is used to recreate some of the frequency-response, time and amplitude variations human listeners’ experience, but in such a way that the recordings also produce a useable stereo image through loudspeakers. This paper presents a finite element model able to simulate the effects on sound propagation ...
S. Carcangiu, B. Cannas, M. Usai, and G. Concu
Department of Electric and Electronic Engineering, Cagliari, Italy
Department of Structural and Infrastructural Engineering and Geomatics, Cagliari, Italy
An experimental program has been developed, with the purpose of evaluating the reliability in building diagnosis and characterization of an integrated analysis of several parameters, associated with acoustic waves propagating through the material. The Direct Transmission Technique has been applied. In this paper we developed a numerical model using the Transient Acoustics-Piezoelectric ...
Y.F. Wang, Y.S. Wang, L. Wang
Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing, China
Department of Mechanical Engineering, Østfold University College, Halden, Norway
We show in this paper that by careful design of the geometry of the resonators, complete bandgap with relatively low center frequency can be obtained for 2D and 3D Phononic Crystals with resonators. The generation of the bandgap is due to the local resonance of the unit cell. Spring-mass and spring-pendulum models are developed to predict the boundaries of the complete bandgap. The predicted ...
Modeling Thermal Bridging at Interface Conditions: Analysis of Solutions for Reducing Thermal Bridges Effects on Building Energy Consumption
C. Balocco, E. Marmonti
Dipartimento di Energetica, Università di Firenze, Firenze, Italy
In Europe considerable building activity can be expected over the coming decades; Net Zero Energy Buildings refers to a building with minimal power, until maximum 15 kW/m^2. In both cases this requires very well insulated buildings with minimal thermal bridges. Concrete balconies, that extend the floor slab through the building envelope, are a common example of thermal bridging, where structural ...
A. Giusti, A. Andreini, B. Facchini, F. Turrini, Ignazio Vitale
Department of Energy Engineering, University of Florence, Florence, Italy
Avio, Turin, Italy
In this work a thermoacoustic analysis of a tubular combustor with an advanced lean injection system is presented. The performed analysis is based on the resolution of the eigenvalue problem related to an inhomogeneous wave equation which includes a source term representing heat release fluctuations (the so called Flame-Transfer-Function, FTF) in the flame region. The effect of the mean flow is ...
M. Quinn, D. Whitlow, O.D.S. Taylor, M.H. McKenna
 Engineer Resource and Development Center, United States Army Corps of Engineers, Vicksburg, MS, USA
Bridge piers and abutments makeup the bridge substructure and transmit loads from the superstructure to the bridge foundation material (Figure 1). The bridge abutment serves three purposes: to provide vertical support to the bridge superstructure where the bridge ends, to connect the bridge with the approach roadway, and to retain roadway base materials. There are several types of abutment ...
R. C. Thiagarajan
ATOA Scientific Technologies Private Limited
Ultrasonic acoustic waves usually encounter interfaces with significant impedance mismatch in practical medical or industrial imaging applications. A transparent interface can help to improve the performance of medical and industrial imaging and overall innovative applications. Similarly, a broadband total reflection interface can help to improve the architectural or transportation barrier ...
Dr. Shekhawat is currently the General Manager for New Products Development at Secure Meters Ltd., Udaipur. Prior to this, he was with CEERI, Pilani for 23 years. He has a Ph.D., MS, M. Sc. (Physics) and BE (EEE) from BITS, Pilani. He is the recipient of several honours including the DAAD Fellowship, Germany and National Science Talent Fellowship. His areas of research include Ultrasonic ...