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Article
Publication date: 4 January 2019

Gülbanu Şenay, Metin Kaya, Engin Gedik and Muhammet Kayfeci

The purpose of this study is to numerically investigate the heat transfer enhancement by using two different nanofluids flow throughout the square duct under a constant heat flux…

Abstract

Purpose

The purpose of this study is to numerically investigate the heat transfer enhancement by using two different nanofluids flow throughout the square duct under a constant heat flux (500 × 103 W/m2).

Design/methodology/approach

In numerical computations, ANSYS Fluent code based on the finite volume method was used to solve governing equations by iteratively. Water, Al2O3-water and TiO2-water nanofluids were used for different flow velocities changing 1 m/s to 8 m/s (i.e. Reynolds number varying from 3,000 to 100,000).

Findings

The results were compared with results published previously in the literature and close agreement was observed especially considering Dittus and Boelter correlation for water. It was found that from the obtained results, increasing flow velocity and volume fractions of nanoparticles has caused to increase Nu number for all cases. Besides, variations of pressure drop, Darcy friction factor are presented graphically and discussed in detail. The results are consistent with a deviation of 1.3 to 15 per cent with the results of other researchers.

Originality/value

The effects of the Re numbers and volume fractions of nanoparticles (0.01 ≤ Φ ≤ 0.04) on the heat transfer and fluid flow characteristics such as average Nu number, pressure drop (ΔP) and Darcy friction factor (f) were investigated.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 April 2002

Sait N. Yurt, I˙brahim Özkol, Metin O. Kaya and Chingiz Haciyev

In this study the design of motion‐based flight simulators is carried out by specifying the performance required of the motion cueing mechanism, to generate translational and…

Abstract

In this study the design of motion‐based flight simulators is carried out by specifying the performance required of the motion cueing mechanism, to generate translational and angular motions as a 6–3 Stewart Platform Mechanism (SPM). These motions are intended to approximate the specific forces and angular accelerations encountered by the pilot in the simulated aircraft. Firstly, the dynamics of this 6–3 SPM is given in closed form as in our earlier study. Then, for the control of obtained dynamic model, a leg‐length based PD algorithm is applied. In the optimization of the applied PD algorithm's coefficients, Real Coded Genetic Algorithms are used. So as to have faster and effective system's performance, the fitness function chosen, in Genetic Algorithms, having maximum overshoot value, settling time and steady state error which are obtained from the unit step response. The performance of the system studied is compared to the similar studies in the literature exist.

Details

Aircraft Engineering and Aerospace Technology, vol. 74 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 22 May 2007

Ozge Ozdemir Ozgumus and Metin O. Kaya

This study aims to carry out flutter stability and vibration analysis of a uniform hingeless rotor blade in hovering flight conditions.

Abstract

Purpose

This study aims to carry out flutter stability and vibration analysis of a uniform hingeless rotor blade in hovering flight conditions.

Design/methodology/approach

The perturbation equations are obtained using the governing differential equations of motion derived in Part I (Aircraft Engineering and Aerospace Technology, Vol. 79 No. 2, 2007). The differential transform method (DTM) is applied to the perturbation equations of motion and the transformed equations are coded in the computer package Mathematica.

Findings

The effects of the built‐in pretwist angle and the rotational speed ratio on the natural frequencies are investigated and the results are compared with the results in literature.

Originality/value

This study, in carrying out an analysis of flutter stability and vibration of a uniform hingless rotor blade, is in good agreement with previous studies in the literature.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 30 January 2007

Ozge Ozdemir Ozgumus and Metin O. Kaya

This study aims to derive the kinetic and the potential energy expressions of a rotating uniform hingeless rotor blade and the aerodynamic loads that act on the blade element in…

1317

Abstract

Purpose

This study aims to derive the kinetic and the potential energy expressions of a rotating uniform hingeless rotor blade and the aerodynamic loads that act on the blade element in hovering flight conditions.

Design/methodology/approach

The blade is modeled as an Euler‐Bernoulli beam. The governing partial differential equations of motion and the associated boundary conditions are derived using the Hamilton's principle.

Findings

The derivations of the energy expressions and the aerodynamic loads are made in a detailed way by including several explanatory tables. The resultant equations of motion are in good agreement with the literature. Additionally, in this work the hub radius effect is included in the equations of motion.

Originality/value

Arguably this study achieves a breakthrough in deriving the kinetic and the potential energy expressions of a rotating uniform hingeless rotor blade and the aerodynamic loads that act on the blade element in hovering flight conditions.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 May 2006

Metin O. Kaya

To perform the flapwise bending vibration analysis of a rotating cantilever Timoshenko beam.

1882

Abstract

Purpose

To perform the flapwise bending vibration analysis of a rotating cantilever Timoshenko beam.

Design/methodology/approach

Kinetic and potential energy expressions are derived step by step. Hamiltonian approach is used to obtain the governing equations of motion. Differential transform method (DTM) is applied to solve these equations.

Findings

It is observed that the ρIΩ2θ term which is ignored by many researchers and which becomes more important as the rotational speed parameter increases must be included in the formulation.

Originality/value

Kinetic and potential energy expressions for rotating Timoshenko beams are derived clearly step by step. It is the first time, for the best of author's knowledge, that DTM has been applied to the blade type rotating Timoshenko beams.

Details

Aircraft Engineering and Aerospace Technology, vol. 78 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 June 2004

Ergüven Vatandaş, İbrahim Özkol and Metin O. Kaya

In this study, dynamic mesh method is implemented on a real coded genetic algorithm to demonstrate gain in computational time as well as in higher performance for optimized…

Abstract

In this study, dynamic mesh method is implemented on a real coded genetic algorithm to demonstrate gain in computational time as well as in higher performance for optimized parameters. Since the differences developed at each step in geometries of new members are not significant, therefore, it is possible to use dynamic mesh methods for new members. In this work, because the population members are obtained by modifying the pervious ones, each member is considered as one step of geometry‐change of a deforming body, for examples, a wing inflating, deflating or cambering.

Details

Aircraft Engineering and Aerospace Technology, vol. 76 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Book part
Publication date: 13 March 2019

Zeynep Koçer

Since 2004, Turkish cinema has been witnessing an emergence of horror genre, now flooded with stories of possession by malevolent jinn, as transgressive, volatile figures of…

Abstract

Since 2004, Turkish cinema has been witnessing an emergence of horror genre, now flooded with stories of possession by malevolent jinn, as transgressive, volatile figures of abjection. These female-centred narratives rely both on Islamic cosmology and myths and folktales of pre-Islamic Anatolian oral culture. The chapter will first explore the reasons horror has been neglected in the century-long history of cinema in Turkey and move on to highlight the socio-economic, cultural, and political contexts that were catalysts for the horror genre’s emergence. Then, the chapter will discuss the codes and conventions of the genre and explore the unique place of Alper Mestçi’s 2007 film Haunted (Musallat), among its contemporaries in terms of the ways in which the film challenges these established codes and conventions. In analysing Haunted, the chapter will use the theoretical framework of Barbara Creed, Carol J. Clover and Julia Kristeva to discuss the monstrous-feminine and masculinity as abjection.

Article
Publication date: 19 June 2023

Okan Çolak and Halil Ibrahim Karakan

This study aims to determine museum experiences by analyzing the TripAdvisor reviews of the museum visitors in Gaziantep and offer suggestions for improving the visitors'…

Abstract

Purpose

This study aims to determine museum experiences by analyzing the TripAdvisor reviews of the museum visitors in Gaziantep and offer suggestions for improving the visitors' experiences by taking museum curators' opinions.

Design/methodology/approach

The case study method was used as one of the qualitative approaches in the study. The research comprises two stages. TripAdvisor reviews about five museums in Gaziantep were analyzed in the first stage, and museum curators' opinions on the visitor complaint reasons and solution suggestions were discussed in the second stage.

Findings

The study showed that satisfying or non-satisfying experience factors might differ according to visitors, museum curators and both visitors and museum curators. Therefore, each museum curator should effectively manage every component of visitor experience factors by its target audience.

Research limitations/implications

Although this study has some valuable findings and contributes to the literature, it also has limitations. The study's sample consists of five museums in Gaziantep. Further studies can be carried out on a larger population and sample. The data for determining visitor experiences, the first stage of the research, were obtained only from an online platform (TripAdvisor).

Practical implications

The proposed model provides a holistic perspective on evaluating and managing visitor experience. There may be structural problems (small size of the museum area, lack of parking spaces and elevators, etc.) with the museum beyond the manager's control. Also, the lack of information and communication (limited concept, lack of artifacts, etc.) causes criticisms of the museum.

Social implications

This paper contributes to the museum management literature with a model for enriching the quality of the museum experience and increasing the museum's attractiveness. The study showed that museums contribute to the visitor's experience in all dimensions. While visitors thought museums primarily contribute to object experience, museum curators thought museums contribute more to visitors' cognitive experience and other experience elements.

Originality/value

The present study analyzed the visitor comments and the opinions of museum curators from a holistic perspective, considering the internal and external factors that are effective in the visitor experience, and revealed the reasons for the visitors' negative experience and the solution suggestions toward the improvement of the visitor experience.

Details

Journal of Hospitality and Tourism Insights, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2514-9792

Keywords

Article
Publication date: 23 December 2022

Visar Hoxha, Hasan Metin, Islam Hasani, Elvida Pallaska, Jehona Hoxha and Dhurata Hoxha

The overall purpose of the study is to identify the gender differences in color preferences for different types of interior space in the residential built environment in…

Abstract

Purpose

The overall purpose of the study is to identify the gender differences in color preferences for different types of interior space in the residential built environment in Prishtina, Kosovo. Additionally, the purpose of the study is also to identify the gender differences in the emotions that various colors trigger in occupants of the mainly residential built environment.

Design/methodology/approach

The present study uses a quantitative study and χ2 test to analyze whether the variables formulated by study hypotheses are dependent on gender. The data are gathered by a questionnaire to measure the color preferences of the respondents. The study uses a questionnaire with eight questions that were distributed to 303 respondents using the stratified probability sampling, using gender as the main stratum for probability sampling.

Findings

The study finds that there are no gender differences in color preferences for home lighting, living room, bedroom, study room and children’s rooms in the residential built environment. The study also finds that there is a gender difference in color preferences that trigger emotions of tranquility, stability and security and warmth and pleasure in both male and female respondents.

Practical implications

The implications of this study are that real estate and facility management firms must conduct marketing research to identify the color preferences for both housing interior and exterior depending on the different local cultural backgrounds of clients. Firms must provide training for real estate agents on the color preferences of clients for various types of spaces and the differences that may exist based on gender but also other variables.

Originality/value

The present study is the first quantification of gender differences in color preferences of the residential built environment in the capital city of an understudied region such as Kosovo.

Details

Facilities , vol. 41 no. 3/4
Type: Research Article
ISSN: 0263-2772

Keywords

Book part
Publication date: 25 September 2023

Mehmet Bağış, Mehmet Nurullah Kurutkan and Liridon Kryeziu

This research aims to determine the contribution of publications in the context of Türkiye to the international entrepreneurship literature between 2005 and 2022. We examined 471…

Abstract

This research aims to determine the contribution of publications in the context of Türkiye to the international entrepreneurship literature between 2005 and 2022. We examined 471 articles published in international journals in the Web of Science (WoS) Core Collection database using bibliometric analysis techniques. We analyzed the data with the software Biblioshiny+Bibliometrix, SciMAT, and VOSViewer. We used performance, theme and evolution, co-authorship, and document analysis in data analysis. Performance analysis findings show that the most publications were made in 2021, the journal with the most publications was sustainability, and the author with the most publications was Bakır, C. Theme and evolution analysis revealed that the motor themes were corporate entrepreneurship, gender and entrepreneurial intentions in the first period (2005–2014), while institutional entrepreneurship stood out as the niche theme. In the second period (2015–2022), “corporate entrepreneurship” and “performance” emerged as the motor themes, while the niche themes in this period were “Syrian refugees” and “entrepreneurial intentions.” Document analysis findings show that the most studied entrepreneurship types are gender, family, corporate, social, and small business, respectively. In addition, immigrant/refugee entrepreneurship is emerging as a new topic, while indigenous entrepreneurship, informal entrepreneurship, sustainable entrepreneurship, and religion entrepreneurship are the most minor studied topics in entrepreneurship. Evidence-based decision-making inputs were obtained for those holding the resource allocation authority in Türkiye. Policymakers and funders, as well as individuals and institutions that want to design the future in terms of resources, can benefit from the findings and analysis of this chapter. Türkiye, which ranks 26th in the world regarding entrepreneurship, must develop a policy based on data.

Details

Entrepreneurship Development in the Balkans: Perspective from Diverse Contexts
Type: Book
ISBN: 978-1-83753-455-5

Keywords

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