Karadeniz, Ziya Haktan
Loading...
Profile URL
Name Variants
Karadeniz, Z. Haktan
Karadeniz, Z. H.
Karadeniz, Z. H.
Job Title
Email Address
haktankaradeniz@iyte.edu.tr
Main Affiliation
03.06. Department of Energy Systems Engineering
Status
Current Staff
Website
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Sustainable Development Goals
1NO POVERTY
0
Research Products
2ZERO HUNGER
0
Research Products
3GOOD HEALTH AND WELL-BEING
1
Research Products
4QUALITY EDUCATION
0
Research Products
5GENDER EQUALITY
0
Research Products
6CLEAN WATER AND SANITATION
0
Research Products
7AFFORDABLE AND CLEAN ENERGY
1
Research Products
8DECENT WORK AND ECONOMIC GROWTH
0
Research Products
9INDUSTRY, INNOVATION AND INFRASTRUCTURE
0
Research Products
10REDUCED INEQUALITIES
0
Research Products
11SUSTAINABLE CITIES AND COMMUNITIES
0
Research Products
12RESPONSIBLE CONSUMPTION AND PRODUCTION
0
Research Products
13CLIMATE ACTION
0
Research Products
14LIFE BELOW WATER
0
Research Products
15LIFE ON LAND
0
Research Products
16PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
17PARTNERSHIPS FOR THE GOALS
0
Research Products
Documents
32
Citations
542
h-index
11
Documents
28
Citations
423
Scholarly Output
12
Articles
10
Views / Downloads
3227/1399
Supervised MSc Theses
1
Supervised PhD Theses
0
WoS Citation Count
21
Scopus Citation Count
45
Patents
0
Projects
0
WoS Citations per Publication
1.75
Scopus Citations per Publication
3.75
Open Access Source
6
Supervised Theses
1
| Journal | Count |
|---|---|
| Aircraft Engineering and Aerospace Technology | 1 |
| Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi | 1 |
| Energy and Buildings | 1 |
| International Journal of Heat and Mass Transfer | 1 |
| International Journal of Thermofluids | 1 |
Current Page: 1 / 3
Scopus Quartile Distribution
Competency Cloud
12 results
Scholarly Output Search Results
Now showing 1 - 10 of 12
Article Citation - WoS: 2Citation - Scopus: 2Sleep Quality: Design of Bedroom Ventilation and Evaluation Within the Scope of Current Standards(Elsevier Science Sa, 2025) Cobanoglu, Nur; Karadeniz, Ziya Haktan; Sofuoglu, Sait Cemil; Toksoy, MacitIndoor air pollution is one of the leading environmental risks to public health considering people now spending nearly 90 % of their day in indoor environments. A significant portion of this time indoors is devoted to sleeping, making it crucial to address the impact of indoor environmental conditions on sleep quality. International ventilation standards such as ASHRAE and CEN, as well as country-specific guidelines, offer valuable recommendations for ventilation design in residential buildings, including bedrooms. This study aims to evaluate the importance of determining ventilation rates in sleeping spaces using Indoor Air Quality Procedure (IAQP) compared to Ventilation Rate Procedure (VRP) in accordance with current standards. Here, the IAQP approach for determining air flow rate is based on the CO2 balance by maintaining CO2 levels in any sleeping environment below specified upper limits of 750 ppm and 1000 ppm. This study focused on the adult population, which forms the majority of society, with analyses conducted for both single and double occupancy sleeping conditions. The volume of environment where ventilation is not required during sleep (Vf) is inaccessible in conventional sleeping environments (10-21.6 m3 per person). Therefore, proper ventilation is of great importance for any sleeping space that is smaller than the Vf. The results of the analyses show that for the conventional sleeping volumes, CO2 levels reach 750 ppm (upper limit for comfortable sleep) in the first hour and increase to the disturbed sleep zone in about 2 h. Additionally, a chart outlining the necessary ventilation flow rates is suggested for maintaining maximum CO2 concentrations of 750 and 1000 ppm during different sleep durations and in various sleeping environments with varying volumes. Finally, the ventilation rates determined based on unit area and/or occupancy levels in standards (referred to as VRP) may not always be adequate or may be excessive in order to maintain CO2 concentrations below the recommended limits of 750 and 1000 ppm. It is advised to utilize demand-controlled ventilation by considering the system design as recommended by IAQP.Article Citation - WoS: 1Citation - Scopus: 1Euler–Euler Numerical Model for Transport Phenomena Modeling in a Natural Circulation Loop Operated by Nanofluids(Springer, 2025) Kamenik, B.; Vovk, N.; Elcioglu, E.B.; Sezgin, F.; Ozyurt, E.; Karadeniz, Z.H.; Ravnik, J.This paper explores a computational approach to model multiphase heat transfer and fluid flow in a natural circulation loop utilizing nanofluids. We propose and implement an Euler–Euler framework in a CFD environment, incorporating an innovative boundary condition to preserve mass conservation during thermophoretic particle flux. The model’s accuracy is verified through a one-dimensional example, by comparing results against both an Euler–Lagrange model and an in-house finite volume solution. Experimental validation is conducted with aluminum oxide nanofluids at varying nanoparticle concentrations. We prepared the nanofluids and measured their thermophysical properties up to 60∘C. We assess the thermal performance of the nanofluid in natural circulation loop at different heating powers via experiment and numerical simulations. The findings reveal that the heat transfer enhancement offered by the nanofluid is modest, with minimal differences observed between the proposed Euler–Euler approach and a simpler single-phase model. The results underscore that while the Euler–Euler model offers detailed particle–fluid interactions, its practical thermal advantage is limited in this context. © The Author(s) 2025.Master Thesis Effects of Electrical Dynamic Response of Doubly Fed Induction Generator Type Wind Turbines on Their Mechanical Systems During Single and Multiple Faults(2023) Coşgun, Mert; Karadeniz, Ziya Haktan; Altın, MüfitIn the early stages of wind turbine technology, the focus was on the separate development of mechanical and electrical systems and research was carried out only in these areas. Today's modern wind turbine designs, which have reached megawatt sizes, continue to be more cost-effective and dependable for countries to achieve their renewable energy targets. In this direction, wind turbine research and development processes have now started to focus on both mechanical and electrical systems and their subsystem interactions. In this thesis study, it is aimed to investigate the effects of the response of electrical control systems on towers components during grid faults. A doubly fed induction generator is used for power generation and power systems including converters and control systems are modelled in MATLAB/Simulink. Simulations were designed in Simulink to test the grid-connected wind turbine model and the Fault Ride Through condition that causes voltage drops in the grid connection lines; the response of the control system and electromagnetic torque output in the relevant case were sent to the mechanical system analysis tool Horizonal Axis Wind Turbine Simulation Code 2 to observe the effects on the mechanical system. In Horizonal Axis Wind Turbine Simulation Code 2, the interaction of the main bodies against forces and limits is analyzed and the results are reported graphically. The state of the system without fault and data with the faults are analyzed comparatively. It has been observed that the reactions of the electrical power systems during grid failure influence the mechanical systems.Article Citation - WoS: 1Citation - Scopus: 1Numerical and Experimental Investigation of Aspect Ratio Effect on Aerodynamic Performance of Naca 4415 Airfoil Section at Low Reynolds Number(Assoc Mechanical Engineers Technicians Slovenia, 2025) Uemuetlue, Hatice Cansu Ayaz; Kiral, Zeki; Karadeniz, Ziya HaktanIn this study, the effect of aspect ratio on the aerodynamic coefficients is investigated for a NACA 4415 airfoil profile. Four different aspect ratios which are 3, 5, 7, and 9 are evaluated with the computational fluid dynamics (CFD) simulations and the experiments. The CFD studies are performed using a threedimensional (3D) computational domain and by using the k-omega shear stress transport (SST) turbulence model for turbulence calculations. The measurements of the aerodynamic forces are carried out in open jet type wind tunnel using a three-component balance. CFD and experimental studies are performed at angles of attack from 0 degrees to 25 degrees and Reynolds number 85<middle dot>103. The results show that as the aspect ratio increases, separation points move towards the leading edge of the airfoil and the stall angle reduces. Furthermore, it is observed that the lift coefficients increase with the increasing aspect ratio. The results obtained indicate that there is a harmony between the experimental data and the CFD solutions.Article Advancing Nanofluid Numerical Modelling: a Novel Euler–Lagrange Method With Experimental Validation(Elsevier Ltd, 2025) Vovk, N.; Kamenik, B.; Elcioglu, E. Begum; Ozyurt, E.; Karadeniz, Z. H.; Turgut, A.; Ravnik, J.We present a novel approach to numerical modelling of thermal nanofluids based on the Euler-Lagrange method. This approach overcomes the challenge of extremely fine temporal discretization, which previous Euler-Lagrange nanofluid numerical models struggled to address, while also avoiding the need for too many Lagrangian nanoparticles. A numerical uncertainty assessment method is adapted for the proposed approach. The model is validated with a simple verification case and applied to simulate a closed natural circulation loop heat exchanger operating with heating power ranging from 10 W to 50 W and nanoparticle volume fractions of 0.5% to 2%, using an Al2O3-water nanofluid. Results are compared with experimental temperature measurements and an Euler-Euler implementation of the same nanofluid. The model is also applied to simulate the natural convection inside a vertical enclosure, studied experimentally by other authors. The proposed novel approach demonstrates agreement with both experimental data and the Euler-Euler implementation, effectively capturing the overall behaviour of nanofluids. We establish, that the interplay of multiple transport phenomena, that occur in nanofluid operated devices, can be difficult to completely reproduce numerically within the framework of current modelling assumptions.Article Citation - WoS: 1Citation - Scopus: 1Investigation of Flow and Heat Transfer Performance of Gyroid Structure as Porous Media(Turkish Soc Thermal Sciences Technology, 2024) Genc, Alper Mete; Karadeniz, Ziya HaktanThere are active and passive methods used to improve heat transfer. One of the passive methods is utilising porous media with high heat transfer surface area. Porous media are divided into two groups: regular and irregular structures. One of the regular structures is triply periodic minimal surfaces (TPMS), which have been studied quite frequently recently. In this study, heat transfer and flow analysis of a Gyroid geometry, one of the most used TPMS in the literature, is investigated numerically considering the conjugate heat transfer conditions. A single porosity is considered (epsilon = 0.6), and aluminium, ceramic and PLA are selected for the heat exchanger material to examine the temperature change in the heat exchanger. To understand the different flow characteristics, Reynolds numbers are assumed to be 19.12, 95.61 and 172.09. The fluid inlet temperature is assumed to be constant at 298.15 K, and the initial temperature of the heat exchanger is assumed to be constant at 278.15 K to be consistent with the regenerative heat recovery temperature difference in ventilation standards. Nusselt numbers under different operating conditions are compared, and it is the ceramic material with low thermal diffusivity is at the highest level despite its low thermal conductivity. At the highest Reynolds number, it provided approximately 6% better heat transfer than the aluminium heat exchanger.Article Citation - Scopus: 21The Developing Flow Characteristics of Water - Ethylene Glycol Mixture Based Fe3o4 Nanofluids in Eccentric Annular Ducts in Low Temperature Applications(Elsevier, 2022) Çobanoğlu, Nur; Banisharif, Alireza; Estelle, Patrice; Karadeniz, Ziya HaktanNatural circulation loops with double pipe heat exchangers at heating and cooling ends have a potential to be used in the refrigeration systems as an alternative to suction line heat exchangers. The heat transfer capability of such natural circulation loops depends on the geometrical parameters as well as thermophysical properties of the working fluid. This study aims to investigate the effect of water-ethylene glycol mixture based Fe3O4 nanofluids (0.01, 0.05 and 0.1 vol.%) on the annular flow propagation and heat transfer in the annuli of double pipe heat exchanger at low pressure side of the refrigeration cycle. In addition to increased non-dimensional velocity values due to the lower viscosity and higher non-dimensional temperature values with expanded temperature gradient, improved heat transfer by nanofluids shows that they can be used as secondary heat transfer fluids at low-pressure side in refrigeration systems. Although the maximum transferred (13.6% improvement compared to base fluid) heat observed for the highest concentration, the nanofluids with smallest concentration has the minimum pressure drop value (25% reduction compared to base fluid) and the highest performance evaluation criteria (PEC) value (PEC = 1.08) with tiny increase in exergy destruction (1.45% compared to base fluid)Article Citation - WoS: 1Citation - Scopus: 1Experimental Investigation of Naca 4415 Airfoil Using Vibration Data for Stall Detection(Emerald Group Publishing, 2023) Ayaz Ümütlü, Hatice Cansu; Kıral, Zeki; Karadeniz, Ziya HaktanPurposeThe purpose of this study is to identify the possible relation between the vibration and the stall by using the vibration response of the airfoil. For this purpose, the root mean square values of the acceleration signals are evaluated to demonstrate the compatibility between the stall angles and the vibration levels. Design/methodology/approachAn experimental study is conducted on NACA 4415 airfoil at Reynolds numbers 69e3, 77e3 and 85e3. Experiments are performed from 0 & DEG; to 25 & DEG; of the angles of attack (AoA) for each Reynolds number condition. To observe the change of the vibration values at the stall region clearly, experiments are performed with the AoA ranging from 10 & DEG; to 25 & DEG; in 1 & DEG; increments. Three acceleration sensors are used to obtain the vibration data. FindingsThe results show that the increase in the amplitude of the vibration is directly related to the decrease in lift. These findings indicate that this approach could be beneficial in detecting stall on airfoil-type structures. Originality/valueThis study proposes a new approach for detecting stall over the airfoil using the vibration data.Article Citation - WoS: 3Citation - Scopus: 3Investigation of External Magnetic Field Effect on the Performance of Ferrofluid-Based Single-Phase Natural Circulation Loops(Elsevier, 2023) Bozkır, Selim Can; Çobanoğlu, Nur; Doğanay, Serkan; Karadeniz, Ziya Haktan; Elçioğlu, Elif Begüm; Turgut, AlpaslanThe goal of this study is to investigate the performance of a Single-Phase Natural Circulation mini Loop (SPNCmL) operating under the influence of an external magnetic field (EMF). For this purpose, a numerical SPNCmL model working with Fe3O4 ferrofluids (1-3 vol%.) under the influence of an EMF is developed to reflect the effect of a NdFeB permanent magnet with a remanence of 1.22 T located at the outlet of the cooler-end for the magnetic field generation. System characteristics such as temperature difference at heater-end (& UDelta;Theater) and maximum temperature (Tmax) and performance in terms of effectiveness (& epsilon;) are investigated. In addition, the effect of EMF on boundary layer energy transport along the cooler-end is evaluated in terms of the change in the local Nusselt number. Applying an EMF dramatically affects the system performance in terms of an increase in & UDelta;Theater and & epsilon;, respectively up to 34% and 25% compared to those with water. Tmax values are obtained by up to 9% higher for Fe3O4 ferrofluids compared to water, while applying EMF results in an increment in Tmax by up to 5%. Improved heat transfer performance by employing EMF at the cooler-end outlet of the SPNCmLs emphasizes their potential in cooling applications.Article Eşli çalışan düşey eksenli türbin performansının iki boyutlu benzetimi(2023) Akgül, Ufuk; Kökey, İskender; Turgut, Alpaslan; Karadeniz, Ziya HaktanRüzgar enerji santralindeki (RES) türbinlerin birbirine göre konumları oldukça önemlidir. Bu açıdan önemli hususlardan biri de, birbirine yakın konumda çalışan iki düşey eksenli türbinin (DERT) birbirlerinin performansına olan etkisidir. Literatürde gösterilmiş olan, birlikte çalışan DERT’lerin performansındaki yükselişin nedenlerinin araştırılması gerekmektedir. Saha testlerinde rüzgâr hızlarının tam olarak kontrol edilememesi ve düşey eksenli türbinin kanat dışındaki yapısal elemanlarının akış bozucu etkisi olması, problemin daha basit haliyle, iki boyutlu bilgisayar benzetimi yöntemiyle incelenmesini zorunlu kılmıştır. Bu amaçla çalışma kapsamında, düşey eksenli türbinin akışı bozacak parçalarını ihmal ederek, farklı merkezler arası uzaklığa (1,5, 2, 2,5 ve 4) sahip eşli çalışan iki türbinin performansının farklı uç hız oranlarında (0,5, 1, 1,5, 2, 2,5 ve 3 uç hız oranı) tek çalışan türbine göre nasıl değiştiği iki boyutlu bilgisayar benzetimleriyle incelenmiştir. Eşli çalışma durumunda türbin performansının tek çalışmaya göre %26 yükseldiği görülmüştür. Bu yükselişin ana etkeninin blokaj etkisi olduğu, yanal hızların ve iki türbin ara bölgesinde hızlanan akış gibi etkilerin ise daha az olduğu saptanmıştır.