Buffet investigation on airfoils

Download
2021-4
Algül, Kezban Gizem
The aim of the present thesis is to investigate buffet onset characteristics in two-dimensional flow. NACA0012 airfoil was chosen as the geometry in this study since the profile is frequently used for the lifting surfaces of aircraft, which are exposed to high flight loads during transonic flight and this causes buffet and flutter. In addition, it is one of the very few models which was studied for the buffet onset investigation in the literature and detailed wind tunnel test data is available. In the present study, after determining the optimum mesh resolution and the appropriate turbulence model, the results of the steady flow numerical analysis for low and high Reynolds numbers were validated with wind tunnel data. The transient flow is investigated for the buffet onset region of the NACA0012 airfoil and the results are verified with wind tunnel data. The oscillating behavior of the shock wave on the airfoil is investigated through the frequency and the Strouhal numbers of lift, drag, moment and static pressure distributions through time and frequency. The study investigates the primary effectors that stimulate buffet onset and the behavior of the flow during buffet through numerical analyses using Unsteady Reynolds-Averaged Navier-Stokes (U-RANS) Equations. The effects of Mach number, angle of attack and Reynolds number on buffet onset is investigated for the examination of buffet characteristics in detail.

Suggestions

The concept of self in the context of the "despisers of the body" alluded in nietzsche's thus spoke zarathustra
Yazıcı, Irmak; İnam, Ahmet; Department of Philosophy (2008)
This thesis analyses the concept of self with respect to Nietzsche’s (1844- 1900) implications on the “despisers of the body” in Thus Spoke Zarathustra. Nietzsche’s exposition of the self as a varying multiplicity neither within nor out of the body is the basic assumption of this dissertation. In this sense, the place of Nietzschean self considering the evolution of the concept of self through history will be analyzed. The concept of ego (subject) will be discussed as Nietzsche’s critique of the so-called m...
Investigation of the effect of turbulence on entropy generation in turbomachinery
Orhan, Ömer Emre; Uzol, Oğuz; Department of Aerospace Engineering (2014)
The aim of this thesis is to apply a newly developed methodology to calculate entropy production. Entropy production calculations have always attracted attention due to its extreme importance in efficiency improvement. Efficiency improvement can be achieved via several optimization techniques and Entropy Generation Minimization (EGM) is one of the most acknowledged ones. When it comes to the design and analysis of turbomachinery components, the performance deterioration due to various real flow effects such...
Data driven landslide hazard assessment using geographical information systems and remote sensing
Süzen, Mehmet Lütfi; Doyuran, Vedat; Department of Geological Engineering (2002)
The purpose of this thesis is to generate and evaluate a concise system of data driven landslide hazard assessment procedure. The Asarsuyu catchment area and Bolu Mountain highway pass are selected for this purpose In this study, three data domains, which are remote sensing products, geological maps and topographical maps are used. The landslides of four different historical periods are interpreted using aerial photographs. Land cover is extracted from satellite images. Thirteen sets of parameter maps are p...
Comprehension of Turkish relative clauses in Broca's aphasics and children
Kükürt, Duygu; Tekman, Hasan Gürkan; Department of Cognitive Sciences (2004)
The aim of this thesis is to test two hypotheses. The first one is about the nature of comprehension impairment in Broca's aphasia, namely the Trace Deletion Hypothesis (TDH), and the other is about the similarity between child and aphasic language, namely the Regression Hypothesis. According to TDH, agrammatic patients are impaired in comprehension of certain structures that are formed by movement transformation whereas they show normal comprehension in canonical structures. TDH proposes that patients use ...
Arthur Danto’s ontology of aesthetics upon pop art
İsmet, Burçak; Parkan, Barış; Department of Philosophy (2014)
The main objective of this dissertation is to examine Arthur Danto’s method of indiscernibles in his theory of aesthetics. In order to explicate this conception, Danto’s method of indiscernibles is elucidated by means of Andy Warhol’s works of Pop Art. Through this study Danto’s critical approach against traditional realism in philosophy of art is examined and Danto’s renewed solution for the reality problem of artworks is exposed with the acquaintance of Warhol’s art. After the examination of Danto’s use o...
Citation Formats
K. G. Algül, “Buffet investigation on airfoils,” M.S. - Master of Science, Middle East Technical University, 2021.