Investigation of fluid rheology effects on ultrasound propagation

Download
2012
Özkök, Ozan
In this study, a mathematical model is developed for investigating the discrete sound propagation in viscoelastic medium to identify its viscoelastic properties. The outcome of the model suggests that pulse repetition frequency is a very important parameter for the determination of relaxation time. Adjusting the order of magnitude of the pulse repetition frequency, the corresponding relaxation time which has similar magnitude with pulse repetition frequency is filtered while the others in the spectrum are discarded. Discrete relaxation spectrum can be obtained by changing the magnitude of the pulse repetition frequency. Therefore, the model enables to characterize the relaxation times by ultrasonic measurements.

Suggestions

Investigation of optical characteristics of PbMoO4 single crystals by spectroscopic ellipsometry
Delice, S.; Isik, M.; Hasanlı, Nızamı; Darvishov, N.H.; Bagiev, V.E. (2022-07-01)
© 2022 Elsevier GmbHIn this study, we investigated the optical properties of PbMoO4 single crystals grown by Czochralski method. Spectroscopic ellipsometry measurements were carried out in the energy region between 1.0 and 5.5 eV at room temperature. X-ray diffraction measurements were achieved for structural characterization. The resulted pattern exhibited one peak belonging to (200) plane. Spectral variations of complex dielectric function, complex refractive index, absorption coefficient and dissipation ...
Investigation of nanoantennas using surface integral equations and the multilevel fast multipole algorithm
Karaosmanoglu, Barıscan; Gur, Ugur Merıc; Ergül, Özgür Salih (2015-07-09)
A rigorous analysis of nanoantennas using surface integral equations and the multilevel fast multipole algorithm (MLFMA) is presented. Plasmonic properties of materials at optical frequencies are considered by using the Lorentz-Drude models and employing surface formulations for penetrable objects. The electric and magnetic current combined-field integral equation is preferred for fast and accurate solutions, which are further accelerated by an MLFMA implementation that is modified for plasmonic structures....
Assessment of SLW-1 model in the presence of gray and non-gray particles
Özen, Guzide; ATEŞ, CİHAN; Selçuk, Nevin; Külah, Görkem (2019-02-01)
In this study, predictive accuracy of Gray Gas and SLW-1 approximations is benchmarked against Spectral Line-Based Weighted Sum of Grey Gases Model (SLW) in multidimensional enclosures involving gray/non-gray absorbing, emitting and scattering particles. Input data required for the radiation code and its validation are provided from two combustion tests previously carried out in a 300 kWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) test rig burning low calorific value Turkish lignite with high vola...
Investigation of the microstructure and hardness of SiCP reinforced aluminum matrix composites
Makszimus, Andrea; Gácsi, Zoltán; Gür, Cemil Hakan (2008-01-01)
The purpose of this study is to find a relationship between the parameters describing the microstructural homogeneity of SiC particle reinforced Al metal matrix composites. The Al-SiC powder mixtures having different particle size combinations were hot-pressed after careful mixing. The optical microscope images of the microstructures were processed by using an image analyzing program; the binary morphology was chosen for characterizing the SiC particle distribution.
INVESTIGATION OF THE MICROSTRUCTURE AND HARDNESS OF SiCP REINFORCED ALUMINUM MATRIX COMPOSITES
MAKSZIMUS, Andrea; GACSI, Zoltan; Gür, Cemil Hakan (2007-10-16)
The purpose of this study is to find a relationship between the parameters describing the microstructural homogeneity of SiC particle reinforced Al metal matrix composites. The Al-SiC powder mixtures having different particle size combinations were hot-pressed after careful mixing. The optical microscope images of the microstructures were processed by using an image analyzing program; the binary morphology was chosen for characterizing the SiC particle distribution.
Citation Formats
O. Özkök, “Investigation of fluid rheology effects on ultrasound propagation,” M.S. - Master of Science, Middle East Technical University, 2012.