Gazi UniversityDepartment of Industrial Design Engineering
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NEWS

  • ABOUT COURSES, PROJECTS AND PUBLICATIONS
  • 2021
    Online

    PRESENTATIONS

    CATIA TV

    Dassault Systemes  tarafından CATIA yazılımına dair etkinlikleri aşağıdaki linkten takip edebilirsiniz.
    Link: www.3ds.com
  • 2021
    Online

    WORKSHOP

    Numesys Etkinlikleri

    Değerli Arkadaşlar,
    Özellikle Ansys merkezinde eğitim ve tanıtım sunumlarının yapıldığı etkinlikleri aşağıdaki linkten takip edebilirsiniz.
    Link: www.numesys.com.tr
  • 2021
    Online

    WORKSHOP

    Grup Otomasyon Etkinlikleri

    Değerli Arkadaşlar,
    Grup Otomasyon tarafından verilen webinarın çok faydalı olacağını düşünüyorum. Webinar konuları için linke bakabilirsiniz.
    Link: www.grupotomasyon.com.tr
  • April 20
    2021
    Online

    WORKSHOP

    Simulation World 2021

    Following a record-setting inaugural event in 2020, Simulation World 2021 is designed to inspire and educate executives, engineers, R&D and manufacturing professionals about the transformative powers of engineering simulation.
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RESUME

  • EDUCATION
  • 2009
    2014
    Ankara, Turkey

    P.hD.

    Gazi University

    Graduate School of Natural and Applied Sciences
    Department of Manufacturing Engineering
  • 2005
    2007
    Karabük, Turkey

    M.Sc.

    Bülent Ecevit University

    Graduate School of Natural and Applied Sciences
    Department of Manufacturing Engineering
  • 2001
    2005
    Karabük, Turkey

    B.Sc.

    Bülent Ecevit University

    Technical Education Faculty
    Manufacturing Engineering Technology
  • ACADEMIC AND PROFESSIONAL POSITIONS
  • 2021
    2024
    Ankara, Turkey

    Structural & Mechanical Design Manager

    Titra Technology

  • 2021
    Cont.
    Ankara, Turkey

    Senior Consultant

    METU WIND Center For Wind Energy Research

    Wind Tunnel Structural & Mechanical Design
  • 2021
    Cont.
    Ankara, Turkey

    Assoc. Prof.

    Gazi University

    Technology Faculty
    Department of Industrial Design Engineering
  • 2011
    2021
    Ankara, Turkey

    Senior Mechanical Design Engineer

    TÜBİTAK SAGE

    Aerodynamic Design Divison and Ankara Wind Tunnel
  • HONORS AND AWARDS
  • 2020
    2020
    Ankara, Turkey

    Academic Publication Incentive Program

    TÜBİTAK

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PUBLICATIONS

  • PUBLICATIONS LISTS
  • 2022

    Experimental and Numerical Investigation of Cutting Forces and Temperatures in Milling of Custom 450 Steel

    Archives of Metallurgy and Materials

    Author: Gokce, Harun
    Stainless steels have a wide usage field, their needs as structural parts are increasing day by day due to their resistance to corrosion and providing sufficient mechanical strength in environments that would cause corrosion. In addition to high mechanical properties of the stainless steels, the low heat transmission coefficients bring problems during machining. In this study, the suitable cutting tool and cutting parameters have been evaluated in terms of cutting forces and the tool temperature, the experimental results and finite element analysis have been compared in the milling of Custom 450 stainless steel which offers especially an excellent working opportunity at high temperature and salinity environment. Milling experiments have been carried out using L16 experimental design for Taguchi method. Four simulations have been made using finite element method with corresponding values in L16 orthogonal array for optimum cutting tool and the results were compared in terms of cutting forces and tool temperature changes.

  • 2022

    Weight Optimization of The Gearbox Using Interior Point

    International Journal of Precision Engineering and Manufacturing

    Author: Avcu, M. Enes; Gökçe, Harun
    Weight is important subject to industry that produce machine like truck, grader etc. Thus, weight optimization problem is challenging area to work at optimization area. A few optimization solution is already exit in literature. However, these algorithms are metaheuristic algorithms. In this study, numerical optimization algorithm implemented for weight optimization problem. The interior point method(IPM) is most powerful algorithm for nonlinear programming. We show the result of IPM algorithm and check against meta-heuristic algorithms.

  • 2021

    Computer-Aided Design and Additive Manufacturing of Bone Scaffolds for Tissue Engineering: State of the Art

    Journal of Materials Research

    Author: Top, Neslihan; Şahin, İsmail; Gökçe, Harun; Gökçe, Hüseyin
    Tissue Engineering (TE) applications are focused on the design and fabrication of computer-aided artificial bone scaffolds with developing Additive Manufacturing (AM) technologies. Three-dimensional (3D) bone scaffold is designed with Computer-Aided Design (CAD) software, it is controlled pore size, and porosity ratio and a systematic production process are followed. In this study, artificial bone scaffold design and manufacturing technologies developed with AM technology have been discussed. The first part of the study is the applications materialized through different design methods such as CAD-based design, image-based design, implicit surface design, Topology Optimization (TO), and space-filling curves, which are used in computer-aided artificial bone scaffold design. Secondly, working principles of various AM technologies such as material extrusion and vat photopolymerization, powder bed fusion, material jetting, and direct writing and advantages and limitations of implementing these technologies in TE are also evaluated. Finally, possible future areas of use of the AM technologies in TE are discussed.

  • 2020

    Evaluation and Optimization of O2 Used Ranque-Hilsch Vortex Tube Performance

    Energy Sources, Part A: Recovery, Utilization, and Environmental Effects

    Author: Gökçe, Harun
    Ranque-Hilsch Vortex Tube (RHVT) is a mechanical system that can make heating and cooling by using basic heat transfer laws with a compressed fluid. Environmentally friendly RHVT is widely used in cooling systems in medicine, electronics, and computer sectors, particularly in the food sector. In this study, the performances of parallel RHVTs in which oxygen (O2) gas is used were reviewed considering different inlet pressures, nozzle materials and orifice numbers. Test results were modelled by multiple linear regression method and a regression equation was derived. Besides, Signal/Noise (S/N) ratios of the designed test results were calculated using Taguchi L16 mix type (4 × 2 2 × 1) orthogonal sequence, and optimum conditions were determined. Throughout the test, hot fluid outlet valve of the counter flow RHVTs having Ø10 mm inner diameter and 100 mm body length was completely left open. As control factors and levels, four different inlet pressures (200, 350, 500, and 650 kPa), four different number of orifices (three, four, five, and six), and two different nozzle materials (brass and polyamide) were selected. For quality characteristics, the maximum temperature gradient (∆T) was determined. In order to determine the effect rates of the control factors on quality characteristics (∆T), variance analysis (ANOVA) was applied to test results at 95% confidence level. According to statistical results, it was determined that the response rates of ΔT values from the control factors were determined as inlet pressure, the number of orifices and nozzle material, respectively. The validity of the optimization was checked with confirmation tests, and the optimization proved to be used in the evaluation of RHVT performances.

  • 2020

    Effect of Straight and Angled Abutments on the Strain on a Zirconia Crown and Implant in the Mandibular Second Molar Region: A FEA Based Study

    Materials and Technology

    Author: Özdoğan, Sertaç; Gökçe, Harun; Şahin, İsmail
    In a literature search no study evaluating implant-supported posterior restorations using zircon crowns with straight and angled abutments was found. In this study, the stress distribution of a zircon-crown restoration that will be prepared by using an angular and straight abutment in a mandibular second-molar deficiency, under functional forces, stress over zircon crown and environmental tissues of implant will be evaluated using the finite-element analysis (FEA) method. The FEA result showed that the use of straight implants contributes to the lowest stresses. The selection of a straight and angular abutment is very important for the balance of distributed loading.

  • 2020

    Investigation of The Effects of Drill Geometry on Drilling Performance and Hole Quality

    The International Journal of Advanced Manufacturing Technology

    Author: Yavuz, Mehtap; Gökçe, Hüseyin; Çiftçi, İbrahim; Gökçe, Harun; Şeker, Ulvi
    In this study, the effects of drill geometry on cutting performance and hole quality in the drilling process were investigated. Two newly developed drill geometries were compared with two commercially available drill geometries. In the drilling tests on GGG50 cast iron, 4 different drills, 4 different cutting speeds and 4 different feed rates were used for L16 experimental design. The drilling tests were performed with and without cutting fluid. The results were evaluated using the axiomatic design method, one of the multi-criteria decision-making methods, in terms of thrust force, surface roughness, deviation on hole diameter and length of adhering workpiece material around the chisel edges. From the obtained results, it was seen that the best results were obtained from one of the newly developed drill geometries. In addition, wear test was carried out without cutting fluid using the drill which performed best. With this best performed drill, after 100 drilling operations in wet and dry conditions and after 1500 drilling operations in dry conditions, SEM images were taken from the used drills. After drilling 100 holes both in dry and wet drilling conditions, there was almost no wear on the drills. However, some adhered workpiece material was seen on the drills. In addition, the amount of adhered workpiece significantly increased in dry drilling condition.

  • 2020

    Ring Orthosis Design and Production by Rapid Prototyping Approach

    Journal of Hand Therapy

    Author: Sarı, İsmail; Şahin, İsmail; Gökçe, Harun; Öksüz, Çiğdem
    Study Design: In this study, ring orthosis design and manufacturing was performed by using rapid prototyping technology. Introduction: Swan neck and boutonniere deformities may occur because of various reasons such as tendon injuries, sharp object injuries, or rheumatic diseases. Although ring orthoses are the most commonly used conservative treatment method for swan neck and buttonhole deformities, they cannot be widely used because they are both difficult to produce and aesthetically unsatisfied with the patients. Purpose of the Study: In this study, it was aimed to manufacture with an orthosis design that is fully compatible, more aesthetic, faster, and easily produced. Methods: 3D printing technologies are used in design and manufacturing. The 3D scanner is used in the measurement process, and the 3D printer is used in the manufacturing process. Results: As a result of the study, a more aesthetically pleasing and comfortable orthosis was made faster. Discussion and Conclusions: As a result of the study, the thickness of the material should not be less than 5 mm.

  • 2019

    Optimisation of Cutting Tool and Cutting Parameters in Face Milling of Custom 450 through the Taguchi Method

    Advances in Materials Science and Engineering

    Author: Gökçe, Harun
    Stainless steels with unique corrosion resistance are used in applications with a wide range of fields, especially in the medical, food, and chemical sectors, to maritime and nuclear power plants. The low heat conduction coefficient and the high mechanical properties make the workability of stainless steel materials difficult and cause these materials to be in the class of hard-to-process materials. In this study, suitable cutting tools and cutting parameters were determined by the Taguchi method taking surface roughness and cutting tool wear into milling of Custom 450 martensitic stainless steel. Four different carbide cutting tools, with 40, 80, 120, and 160 m/min cutting speeds and 0.05, 0.1, 0.15, and 0.2 mm/rev feed rates, were selected as cutting parameters for the experiments. Surface roughness values and cutting tool wear amount were determined as a result of the empirical studies. ANOVA was performed to determine the significance levels of the cutting parameters on the measured values. According to ANOVA, while the most effective cutting parameter on surface roughness was the feed rate ( 50.38), the cutting speed ( 81.15) for tool wear was calculated.

  • 2019

    Optimization of Hydrostatic Thrust Bearing Using Enhanced Grey Wolf Optimizer

    Mechanics

    Author: Şahin, İsmail; Dörterler, Murat; Gökçe, Harun
    The need for precise mechanical and tribological properties of the hydrostatic bearings has made them an interesting study topic for optimisation studies. In this paper, power-loss minimization problems of hydrostatic thrust bearings were solved through Grey Wolf Optimizer (GWO). Grey Wolf Optimizer is a meta-heuristic optimization method standing out with its successful applications in engineering design problems. The power-loss minimization problem of hydrostatic thrust bearings was applied on Grey Wolf Optimizer (GWO) for the first time.  The results obtained were evaluated together with the previous studies conducted and a detailed comparison was made. The most significant innovation of the study is the innovation made in the mathematical model of the GWO.  A new model (Enhanced GWO, EGWO) that increases the variety of valid solutions is proposed. The comparisons made both with GWO and other studies in the literature show that EGWO got the known best fitness value with the highest success rate. The consistency and statistical performance of the EGWO show that this method can be used in the optimization of machine elements.

  • 2018

    Effects of Curvature and Area Distribution on S-Shaped Subsonic Diffuser Performance

    Mechanics

    Author: Gökçe, Harun; Küçük, Umut Can; Şahin, İsmail
    In this work, effects of curvature and area distribution on S-shaped subsonic diffuser performance are computationally investigated with commercially available flow solver Fluent. Free-stream Mach number was taken as 0.75 for all computational runs while sideslip and angle of attack values vary between 0 and 5. Intake performance criterions DC (Distortion Coefficient) and PR (Pressure Recovery) are depicted from computational domain and dependence of these parameters to the varying centerline curvature and area ratio for each flight condition is discussed. Results of the current study indicate that low distortion and high PR values are obtainable with the high curvature at the diffuser entrance and smooth area increase through the duct. Furthermore, it was shown that conventional design approaches as investigated in the current study are strong enough for designing subsonic/transonic S-shaped intake if negative effects that may originate from intake/airframe integrations such as boundary layer ingestion can be neglected.

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TEACHING

  • TEACHING HISTORY
  • Cont.
    2021

    DESIGN PROJECT MANAGEMENT/ETM-404

    B.Sc. - Gazi University

    COURSE DESCRIPTION

    Students learn the concept of project management. Have an idea about how project management will be realized in design.

    Course Objectives:

    Teaching the use of human and physical resources in the process of developing a new project in accordance with the budget determined.

    Course Learning Outcomes:

    Students who attend this course learn the basic of design project management. They can make better design project management based on a scientific basis.

    Textbook:

    1. Ramroth, W.G., Project Management for Design Professionals, AEC Ed., Int. Ed., 2006
    2. Santos, J. M. D., Project Management Absolute Beginner’s Guide, 2012 by QUE Publishing
    3. Kerzner, H., Project Management: A Systems Approach to Planning, Scheduling, and Controlling, 2013.

  • Cont.
    2021

    COMPUTER AIDED DESIGN III/ETM-432

    B.Sc. - Gazi University

    COURSE DESCRIPTION

    Starting design with CATIA V5, working with basic tools, working and smoothing surfaces, advanced surface modelling and Class-A surface methodology.

    Course Objectives:

    To teach advanced modelling techniques in CAD software.

    Course Learning Outcomes:

    Students who attend this course learn the basic of CAD-III. They can use better and more efficient CAD tools while designing.

    Textbook:

    1. Dassault Systemes Online Documents, CATIA V5.
  • Cont.
    2021

    COMPUTER AIDED DESIGN II/ETM-222

    B.Sc. - Gazi University

    COURSE DESCRIPTION

    Introduction and navigating the CATIA V5 environment. Sketcher, Part Design, Drafting and Wireframe & Surface Design workbenches are introduced. 

    Course Objectives:

    Basic concepts of Computer-Aided Design methodology. 2D and 3D modelling techniques are given.

    Course Learning Outcomes:

    Students who attend this course learn the basic of Computer-Aided Design. They can use better and more efficient CAD tools while designing.

    Textbook:

    1. Dassault Systemes Online Documents, CATIA V5.
  • Cont.
    2021

    GRADUATION PROJECT/ETM-410

    B.Sc. - Gazi University

    COURSE DESCRIPTION

    Determination of senior thesis subject. Literature review regarding the selected subject and collecting necessary information. Writing the thesis after determining the information to be included in the thesis. Presentation of the thesis in front of a group. Preparing and submitting the thesis.

    Course Objectives:

    Teaching the use of human and physical resources in the process of developing a new project in accordance with the budget determined.

    Course Learning Outcomes:

    Students who attend this course learn the basic of design project management. They can make better design project management based on a scientific basis.

    Textbook:

    1. Ramroth, W.G., Project Management for Design Professionals, AEC Ed., Int. Ed., 2006
    2. Santos, J. M. D., Project Management Absolute Beginner’s Guide, 2012 by QUE Publishing
    3. Kerzner, H., Project Management: A Systems Approach to Planning, Scheduling, and Controlling, 2013.
  • 2022
    2021

    COMPUTER PROGRAMMING/ETM-109

    B.Sc. - Gazi University

    COURSE DESCRIPTION

    To learn the rules of computer subjects and the concept of programming, programming concept learned in MATLAB language to gain skills for their applications.

    Course Objectives:

    Teaching the use of human and physical resources in the process of developing a new project in accordance with the budget determined.

    Course Learning Outcomes:

    Students who attend this course learn the basic of MATLAB Programming. They can make better programming based on a mathematical rules.

    Textbook:

    1. Halvarson, M., Step by Step Microsoft Visual Studio, 2020.
    2. MathWorks Teaching Assist., Online Matlab Academy, 2021.
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BLOG

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ABOUT

PERSONAL DETAILS
Gazi University Department of Department of Industrial Design Engineering
harungokce@yahoo.ca
+90 312 202 86 33 / 82 61
Senior Mechanical Designer Assoc. Prof. Harun Gökçe

BIO

ABOUT ME

Harun Gokce was born in Çankırı, Turkey in 1983. He received his BS and MS degrees in Mechanical Engineering from BEUN in 2005 and 2008, respectively. Then he got his PhD degree in Manufacturing Engineering from the Gazi University in 2014. He worked in the automotive industry in 2005-2010. Until 2021, he served as Senior Mechanical Design Engineer in the Aerodynamics Division and Structural and Mechanical Design Division for the Defense Industries Research and Development Institute of The Scientific and Technical Research Council of Turkey (TÜBİTAK SAGE). Currently, He lectures at the Department of Industrial Design Engineering at Gazi University Faculty of Technology.

HOBBIES

INTERESTS

art, design, technology