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5th World Congress on Mechanical, Chemical, and Material Engineering, MCM (2019 ; Lisbon, Portugal), In the present study, heating, ventilation and air conditioning (HVAC) vents of a tramcar passenger cabin were designed by utilizing computational fluid dynamics (CFD) analysis. Three dimensional and transient numerical simulations were performed in order to obtain the flow and the temperature fields in the cabin. The time dependent Navier Stokes and energy equations for turbulent flow conditions were solved by a commercial CFD package (ANSYS Fluent). The obtained temperature distribution and the air circulation velocity in the cabin comply with the EN 14750-1 standard for both cooling and heating modes of the air conditioning unit. The proposed vent design provides an improved thermal comfort compared to the existing vent structure in the tramcar. © 2019, Avestia Publishing.

The end of the Cold War has included major changes in international politics and Islam has rapidly replaced “communism” in the role of principal enemy of the Western world. The Clash of Civilizations theory has been used as one of the main instruments of the conflict between Islam and Western world. This theory contends that in the post-Cold War world the crucial distinctions between people will be cultural rather than ideological or economical. According to this theory the 21stcentury will witness struggles between Western civilization and others, especially the Western, Islamic and Confucian civilizations. Therefore, the statistics reflect that a strong social, cultural and economic discrimination and intolerance against Muslim inhabitants called Islamophobia has gradually spread to the European countries since the end of the Cold War. This article aims to analyze the relationships between rising Islamophobia, in Europe and The Clash of Civilisations theory, Soğuk Savaş’ın sona ermesi ile birlikte uluslararası politika önemli değişimlere sahne olurken İslam, komünizm yerine en önemli düşman olarak ikame edilerek, Medeniyetler Çatışması tezi, Batı ile Müslümanlar arasında çatışmayı savunan en önemli araçlardan biri olarak kullanıldı. Bu teoriye göre Soğuk Savaş’tan sonra gelişecek olan çatışmalar ideolojik değil kültürel nedenlerden doğacaktır. 21. yüzyıl Batı uygarlığı ile diğer uygarlıklar arasında, özellikle de Batı, İslam ve Konfüçyüs uygarlıkları arasında çatışmalara sahne olacaktır. Dünyada büyük yankı uyandıran bu teori tartışılırken, istatistikler, Soğuk Savaş’ın sona ermesi ile birlikte Avrupa ülkelerinde Müslümanlara karşı İslamofobi olarak adlandırılan bir sosyal, kültürel, ekonomik ayırımcılık ve hoşgörüsüzlüğün geliştiğini ortaya koymaktadır. Bu makale, Avrupa’da yükselmekte olan İslamofobi ile Medeniyetler Çatışması tezi arasındaki ilişkiyi analiz etmeyi amaçlamaktadır

In this study, the behavior of acoustic waves induced by thermal and mechanical effects and the interaction of these waves with flow fields and rigid walls were investigated. The study focuses on two important effects of the acoustic-fluid dynamic interactions. These effects are termed as 'thermoacoustic convection' and 'acoustic streaming' and are analyzed using computational and experimental techniques. The generation and the short-time behavior of thermoacoustic waves in compressible gas-filled two-dimensional enclosures were investigated first. The vertical walls of the enclosure were heated or cooled to generate the thermoacoustic waves. The numerical solutions were obtained by employing a flux corrected transport (FCT) algorithm for the Euler equations and by coupling these to the viscous and diffusive terms of the fully compressible form of Navier-Stokes equations. When a vertical wall temperature is rapidly changed, the resulting waves induce remarkable pressure-induced flows in the enclosure. The long time effects of the thermoacoustic wave motion on the developing natural convection were studied next. The strength of the pressure waves associated with the thermoacoustic effect and the resulting flow patterns were found to be strongly correlated to the rapidity of the wall heating process. The interactions of mechanically driven acoustic waves with in a viscous fluid were studied next. A standing wave field in a two-dimensional enclosure was created by the vibration of one side wall of the enclosure. The interaction of this wave field with the solid boundaries leads to the production of Schlichting (inner) and Rayleigh (outer) type acoustic streaming flow patterns in the enclosure. The effect of the enclosure height and the amount of maximum wall displacement for vibratory motion were studied primarily. These parameters play significant role in the characteristics of the resulting flow structures. It is found that the streaming patterns vary strongly with a change of the standing acoustic wave form from 'harmonic wave profile' to 'sharp shock wave' type profile. The formation of streaming in an air filled acoustic chamber was also investigated experimentally. The computationally predicted results demonstrate qualitative agreement with the measured pressure values and the visualized streaming flow structures in the experiments.