Mühendislik-Mimarlık Fakültesi Makine Mühendisliği Bölümü Makale Koleksiyonu

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https://hdl.handle.net/20.500.12402/1129

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Lazer kaynağı ile kaynak yapılan alüminyum alaşımlarının mekanik özelliklerinin araştırılması ve kaynak parametrelerinin taguchi ve anova yöntemleri kullanılarak optimizasyonu
(Mehmet BULUT, 2022-12-21) Adin, Mehmet Şükrü
Bu çalışmada, AA2024 alüminyum alaşımı malzemelerin lazer kaynağı sırasında uygulanan farklı kaynak parametrelerinin çekme mukavemeti üzerindeki etkileri araştırılmış ve en uygun kaynak parametrelerini elde etmek için Taguchi ve ANOVA yöntemleri kullanılarak optimizasyonları yapılmıştır. Değişken kaynak parametreleri olarak lazer gücü, darbe süresi, ışın güç yoğunluğu ve darbe enerjisi kullanılmıştır. Sonuçlar, en düşük çekme dayanımının, 1800 W lazer gücünde, 5 ms darbe süresinde, 6000 W/mm2 ışın güç yoğunluğunda ve 9,5 Joule darbe enerjisi kullanılarak elde edildiğini, en yüksek çekme dayanımının ise 2600 W lazer gücünde, 6 ms darbe süresinde, 6500 W/mm2 ışın güç yoğunluğunda ve 9,5 Joule darbe enerjisi kullanılarak elde edildiğini göstermiştir. En yüksek çekme dayanımı (174 MPa) ile en düşük çekme dayanımı (113 MPa) sonuçları karşılaştırıldığında, en yüksek çekme dayanımının en düşük çekme dayanımından %53,98 daha yüksek olduğu bulunmuştur. S/N oranlarına göre, 2600 W lazer gücü, 6 ms darbe süresi, 7000 W/mm2 ışın güç yoğunluğu ve 10,5 Joule darbe enerjisinin AA2024 alüminyum alaşımının lazer kaynağı ile kaynak edilmesi için en optimum kaynak parametreleri olduğu anlaşılmıştır. ANOVA analizine göre ortalama çekme dayanımı üzerinde en etkili parametrenin lazer gücü (%82,45) olduğu belirlenmiştir.
Computer aided numerical damage analysis of the axle shaft
(Ahmet ÇALIK, 2022-09-20) Adin, Hamit; Ergün, Raşit Koray; Adin, Mehmet Şükrü
Today, while transportation is constantly moving forward, costs are increasing. The aim is to obtain light structures that are suitable in terms of weight, sufficient in strength, and to save materials and energy. Axles are not only used in transport vehicles, but also in buses, automobiles and forklifts. Axles must be of a reliable structure due to their place of use. The external effects that the axles are generally exposed to are the applied loads. In this study, the mechanical damage analysis of the axle shaft and the characteristic changes in steel materials as a result of static loading were investigated numerically. In order to observe the mechanical behavior of the axle shaft under various loading conditions, mechanical tests should be supported by numerical analysis. Because the physical causes of damage development can be understood through numerical analysis. The aim of our study is to reach the most suitable values in the design of the variables with the optimization technique of the axle shaft made of AISI 1035 steel. Optimum values were obtained by performing numerical analyzes of the axle shaft designed with Solidworks program. As a result of the analysis, it was observed that deformation occurred at the ends of the axle.
Batman ili antep fıstığı potansiyeli ve kabuklarının biyokütle kaynağı olarak değerlendirilmesi
(Batman Üniversitesi, 2022-06-30) Demir, İdris; Altun, Şehmus; Yaşar, Fevzi
Günümüzde fosil enerji kaynaklarının temininde yaşanan sorunlar ve bu kaynakların sınırlı bir rezerve sahip olmasından dolayı yenilenebilir enerji kaynakları giderek artan bir öneme sahip olmuştur. Fosil enerjinin çevresel etkileri de yenilenebilir kaynakların önemini artıran bir diğer faktör olmuştur. Bu bağlamda başta odun, bitki, tarımsal ve orman kalıntı ve artıklarından oluşan biyokütle yenilenebilir enerji kaynakları arasında önemli bir yere sahiptir. Ülkemizde fındık, fıstık ve ceviz gibi sert kabuklu yemişlerin kabukları yüksek bir atık potansiyeline sahip bir biyokütle kaynağı olarak değerlendirilebilir. Bu biyokütle kaynakları direk olarak (örneğin yakılarak) enerji üretiminde kullanılabildikleri gibi bunlardan farklı yöntemler ile biyoyakıt elde edilmesi de mümkündür. Bu bağlamda ülkemizde yıllık yüksek miktarlarda oluşan bir atık kaynak olarak antep fıstığı kabuklarının biyokütle olarak değerlendirilmesi büyük önem taşımaktadır. Bu çalışmada antep fıstığı kabuklarının biyokütle kaynağı olarak değerlendirilmesi araştırılmıştır. Bu amaçla Batman ve çevresinin antep fıstığı potansiyeli araştırıldıktan sonra farklı yörelere ait fıstık kabuklarının analizi yapılmıştır. Batman 2021 yılı için 963 ton antep fıstığı üretimi ile Şanlıurfa, Gaziantep, Siirt ve Kilis’ten sonra en fazla üretim yapılan il olmuştur. Yapılan analiz sonucu fıstık kabuklarının yüksek oranda (ortalama %45) karbon ve oksijen (ortalama %48) içerdiği belirlenmiştir. Analizi yapılan numunelerin ortalama ısıl değeri ise 15 MJ/kg olarak tespit edilmiştir.
Finite element analysis of safety pin in snowplow equipment
(Hibetullah KILIÇ, 2022-06-30) Adin, Mehmet Şükrü; Adin, Hamit; Ergün, Raşit Koray
Snow plow equipment is produced with chassis connections suitable for trucks, pickup trucks, tractors, construction machines and pick-ups and mounted in front of the vehicles. In this study, the stress and deflection values of the safety pin used in snow plow equipment will be examined by testing with finite element analysis. In this study, a damaged safety pin was analyzed numerically. The damaged safety pin was modeled with Solidworks package program and stress analysis was performed by ANSYS Workbench package program. In this analysis, the properties of the safety pin made of St37 steel were used. As a result , it was observed that the safety pin was damaged due to the stress distribution.
Optimization of welding parameters of AISI 431 and AISI 1020 joints joined by friction welding using taguchi method
(Bilecik Şeyh Edebali Üniversitesi, 2022-06-30) Adin, Mehmet Şükrü; İşcan, Bahattin; Baday, Şehmus
Martensitic stainless steel AISI 431 and low carbon steel AISI 1020 are materials used together in many different industries. However, important problems are encountered when welding (fusion welding) these materials to each other. For this reason, friction welding process (Solid-state welding) is used to join these dissimilar metals. There are very few studies on joining these materials with friction welding. Therefore, the optimization of the welding parameters used in joining these dissimilar steel pairs with friction welding is of great important. In addition, the effects of the factors dependent on friction welding parameters need to be well understood. In this study, AISI 431 and AISI 1020 steel bars were successfully joined by friction welding, and the effects of welding parameters on tensile strength and axial shortening were investigated, and welding parameters were optimized using Taguchi method to obtain quality weld joints. The experimental results of the study showed that the highest tensile strength (573.32 MPa) of the joints was 54.53%, higher than the lowest tensile strength (370.99 MPa), the highest axial shortening (23.18 mm) was 650.16%, higher than the lowest axial shortening (3.09 mm). The optimal parameters for average axial shortening and average tensile strength were determined as A3B1C3 and A3B3C2; and the highest percentage contribution values for axial shortening and tensile strength were found to be 51.55% (rotating speed) and 63.90% (rotating speed); and R2 values for the average axial shortening and average tensile strengths were found to be 97% and 99.3%, respectively.
Dikdörtgen delikli türbülatörlerde delik sayısının ısı geçişine ve basınç düşüşüne etkisi
(Fırat Üniversitesi, 2006) Argunhan, Zeki; Yıldız, Cengiz
Bu çalışmada iç içe borulu ısı değiştirgecinde boru girişine yerleştirilen türbülatörlerin (girdap tip akış üreticilerinin) ısı geçişine ve basınç düşüşüne etkisi deneysel olarak araştırılmıştır. Bu amaçla iç içe borulu ısı değiştirgecinin 60 mm çapındaki iç borunun girişine 55º açılı kanatlara sahip ve kanatlarında 2x7 mm ebadında düzgün sıralanmış birer, ikişer, üçer, dörder ve beşer adet dikdörtgen geometrili delikler bulunan türbülatörler yerleştirilerek, bu türbülatörlerin ısı geçişine ve basınç düşüşüne etkileri araştırılmak üzere deneyler yapılmıştır. İç borunun içinde sıcak akışkan olarak hava, dışında ise soğuk akışkan olarak su geçmektedir. Kullanılan türbülatörlerle aynı yönlü paralel ve zıt yönlü paralel akışta deneyler yapılmıştır.
Dairesel kesitli bir borunun girişine yerleştirilen delikli sabit kanatçıklı dönme üreticinin ısı geçişi ve basınç düşüşüne etkileri
(Pamukkale Üniversitesi, 2006-02-01) Argunhan, Zeki; Yıldız, Cengiz
Bu çalışmada iç içe borulu ısı değiştirgecinde farklı delik sayılı dönme üreticilerin ısı transferine ve basınç düşüşüne etkisi deneysel olarak araştırılmıştır. Bu amaçla değiştirgecin 60 mm çapındaki iç borunun girişine 55º kanat açısına sahip ve kanatlarında birer, ikişer, üçer ve dörder adet dairesel delikler bulunan dönme üreticiler yerleştirilerek deneyler yapılmıştır. Bunlar iç borunun girişine rahat takılıp sökülebilecek şekilde dizayn edilmişlerdir. İç borunun içinden sıcak akışkan olarak hava, iç borunun dışından ise soğuk akışkan olarak su geçmektedir.
Second Law analysis in concentric heat exchangers with vortex flow generators
(Energy Education Science and Technology, 2011) Argunhan, Zeki; Çakmak, Gülşah; Yıldız, Cengiz; Behçet, Rasim
In the present study, the experimental results of heat transfer of a concentric tube heat exchanger were analyzed with respect to Second Law of Thermodynamics to reach the geometric optimal design of the heat exchangers. In order to increase the heat transfer, the vortex generators were placed in the entrance of the inner pipe of the heat exchanger. These vortex generators are 60 mm in diameter having six angled (55°, 65°, 75°, 90°) winglets. The winglets have one rectangular slot in each and are 2×7 mm in dimensions. Experiments were carried out with different Reynolds Numbers. Air as hot fluid and water as cold fluid were passed through the inner pipe and outer pipe of the concentric tube heat exchanger, respectively. The variations of the efficiency and Entropy Generation Number with respect to Reynolds Number are shown in graphics, and the results were discussed.
Experimental investigation of the effects of diesel-like fuel obtained from waste lubrication oil on engine performance and exhaust emission
(Journals & Books, 2010-10) Argunhan, Zeki; Yumrutaş, Recep; Arpa, Orhan
In this study, effects of diesel-like fuel (DLF) on engine performance and exhaust emission are investigated experimentally. The DLF is produced from waste engine lubrication oil purified from dust, heavy carbon soot, metal particles, gum-type materials and other impurities. A fuel production system mainly consisting of a waste oil storage tank, filters, a reactor, oil pump, a product storage tank, thermostats and control panel is designed and manufactured. The DLF is produced by using the system and applying pyrolitic distillation method. Characteristics, performance and exhaust emissions tests of the produced DLF are carried out at the end of the production. The characteristic tests such as density, viscosity, flash point, heating value, sulfur content and distillation of the DLF sample are performed utilizing test equipments presented in motor laboratory of Mechanical Engineering Department, University of Gaziantep, Turkey. Performance and exhaust emission tests for the DLF are performed using diesel test engine. It is observed from the test results that about 60 cc out of each 100 cc of the waste oil are converted into the DLF. Characteristics and distillation temperatures of the DLF are close to those values of a typical diesel fuel sample. It is observed that the produced DLF can be used in diesel engines without any problem in terms of engine performance. The DLF increases torque, brake mean effective pressure, brake thermal efficiency and decreases brake specific fuel consumption of the engine for full power of operation.
The effect of rotary type turbulator placed in entrance of heat exchanger on heat transfer and frictional loss
(Energy Education Science and Technology, 2011) Argunhan, Zeki; Behçet, Rasim; Yakut, Ali Kemal
In this study, improving heat transfer in heat exchangers with paralel flow is gained by using swirl flow. For this purpose, a propeller type of turbulator was placed in the entrance of interior pipe of heat exchanger with paralel flow and the effect of turbulator on the heat transfer and friction losses in steady conditions was experimentally investigated. The effect of production of turbulance for improvement of heat transfer in interior pipe flows and the effects of turbulator on heat transfer and pressure drop are experimentally researched by placing a propeller type of turbulator at the entrance of heat exchanger to produce swirl air flow. In experiment setup, water was used as the fluid on which the heat was transferred and air was used as the fluid from which heat was transferred to the water. By usage of datas obtained from experimental measurements were calculated for Reynolds number ranging from 8000 to 24000 necessary relationships effet on heat transfer and pressure drop. In comparison with empty pipe it was seen that the heat transfer increased at range between 25,5%- 50,3% and the friction losses increased 5 times. Besides, by analyzing the system exergy, the dependence of non-dimensional exergy loss on Reynolds number was drawn to investigate whether this improvement technique is advantageous thermodynamically or not. When comparing the exergy losses in empty pipe and the pipe with a turbulator at approximately same Reynolds numbers, it was seen that exergy loss is 15% higher for empty pipe than that for the pipe with the turbulator. As a result of that information, the improvement technique was proved to be advantageous in thermodynamic manner too. By the usage of turbulator that results in the partial recovery of loss energy, it was proven that the improvement technique was thermodynamically advantageous
Dimension and insulation thickness optimization of circular flat plate solar collectors
(Energy Education Science and Technology, 2011) Argunhan, Zeki
In this study, expressions for optimum radius of a circular flat plate solar collector and the optimum insulation thickness distribution are derived by using the concept of solar gain, which maximizes the life-cycle savings. For the specified condition the optimum radius has been found as 2.14 m and the optimum insulation thickness distribution on back of collectors has been formulized. The insulation material thickness distribution has been determined by performing a detailed dimensional analysis; therefore heat loss is minimized, and results are presented in graphics.
Effect of swirl generators with different sized propeller on heat transfer enhancement
(Energy Education Science and Technology, 2011) Argunhan, Zeki; Yıldız, Cengiz; Çakmak, Gülşah
In this study, the swirl flow that is one of the passive methods is used for increasing the heat transfer coefficient in the concentric heat exchangers. For this purpose, propeller type swirl generators were prepared to test in the experiments. So, the effect of propellers placed in the inner pipe of the concentric heat exchangers on the heat transfer and pressure drop was investigated experimentally. Experiments were undertaken for the Reynolds Number range of 4000-12000 and for both parallel and counter-flow. It is shown that, the propellers rotated freely with the effect of fluid flowed in the inner pipe are swirling flow generator and they have improved heat transfer. In addition that up to 50% enhancements could be accomplished in heat transfer rates with the swirl generators compared to without the swirl generators. In the parallel flow mode, the enhancement was 10% lower than that of counter-flow at the same Reynolds number. On the other hand the pressure losses increase approximately 3 times more than the empty tube related to Reynolds numbers and propeller sizes. As an outcome of the study, the results showed that a rather smaller size but the same capacity heat exchanger could be proposed by using these elements imposing swirling to the fluid flowing through inner pipe.
Evaluation of fly ash and polypropylene in production of composite materials
(Energy Education Science and Technology, 2012) Argunhan, Zeki; Yıldız, Tülay; Haksever, Aysen
More than 10 million tons of fly ash produced in power plants and polypropylene wastes cause environmental pollution in Turkey. Not only the environmental problems they create, but also the fact that demand for raw material sources increases rapidly make fly ashes and waste polypropylene necessary to be researched. In this study the usability of the fly ashes and polypropylene wastes of Soma and Afsin-Elbistan Power Plants in producing new composite materials has been investigated. Materials which possess new properties such as composite type isolation have been formed by melting down the polypropylene wastes that are used as combining elements and by mixing this with fly ash in different percentages. The thermal conductivity, endurance against pressure pull-corrosion, and the rates of water absorption of these materials were analyzed experimentally and both stated and interpreted in the graphics. By this way, these two materials can be recovered by both lessening the environmental problems and providing income for economy by means of saving energy.
Experimental investigation of thermal performance in a concentric tube heat exchanger with wavy inner pipe
(SpringerLink, 2012-06) Argunhan, Zeki; Çakmak, Gülşah; Yücel, Halit Lutfi; Yıldız, Cengiz
In this article, the heat transfer, friction factor, and thermal performance factor characteristics of a concentric-tube heat exchanger are examined experimentally. A wavy inner pipe is mounted in the tube with the purpose of generating swirl flow that would help to increase the heat transfer rate of the tube. The examination is performed for a Reynolds number ranging from 2700 to 8800. An empirical correlation is also formulated to match with experimental data of the Nusselt number using the Wilson plot method. In addition, to obtain the real benefits in using the swirl generator at a constant pumping power, the thermal enhancement factor is also determined. Over the range considered, the increases in the Nusselt number, friction factor, and thermal performance factor are found to be, respectively, about 113 %, 81 %, and 196 % higher than those obtained from a smooth-surface inner pipe.
Effect of the air flow rate of blower on the performance of solar still
(Türk Isı Bilimi ve Tekniği Derneği, 2015-06-01) Argunhan, Zeki; El, Emin; Yücel, Halit Lutfi; Çakmak, Gülşah; Yıldız, Cengiz
Solar distillation is one of the important methods for water purification. This paper examines the performance of solar distillation system at different air flow rate. To increase the performance of distiller, artificial wind was created by fan and suitable wind speed was investigated to increase the amount of water distilled. The experiments were carried out in Elazığ climate conditions. In order to examine the effect of the wind speed on solar distillation system, two stills were manufactured with the size of 1000x1000 mm. One of them was the conventional still which was used as a reference. The other still was used to investigate experimentally the effect of the wind speed. Graphs were drawn for time-dependent changes in the amount of water distilled. It was found that that the productivity of the fan-still distiller was 14.7 % greater than that of a conventional still.
Yapı elemanlarında kullanılan atık lastiklerin ısıl performansının incelenmesi
(Dicle Üniversitesi, 2017-07-01) Argunhan, Zeki
Dünya üzerinde atık olarak değerlendirilen maddelerin büyük bir kısmı geri dönüştürülebilir malzemelerden oluşmaktadır. Atık ya da atıl malzemelerin depolanması ya da uzaklaştırılması Türkiye ve Dünyada geleceğin en büyük problemlerinden biri olarak görülmektedir. Bu problemin en mantıksal çözümlerinden biri atık ya da atıl malzemelerin yeniden kullanılabilirliğinin sağlanabilmesidir. Bir endüstriyel atık olan lastiklerin, beton özeliklerini geliştirmek amacıyla betonun içine katılması oldukça yaygın olarak kullanılmaktadır. Bu doğrultuda, bu çalışmada, enerji verimli binalar için nispeten yüksek mukavemet, düşük yoğunluklu, yüksek ısı ve ses yalıtımı olan yeni beton tipleri elde etmek için deneysel bir çalışma gerçekleştirilmiştir. Bu amaçla, sabit su-çimento oranında, normal agrega yerine hacimce %10, %20, %30, %40, %50 ve %60 oranlarında atık lastik agregası kullanılarak çeşitli beton numuneleri hazırlanmıştır. Deneysel çalışmalarda birim ağırlıkları değişen toplam 6 seri beton üretilmiştir. Üretilen tüm numunelerin mekanik testleri yapılmış ve ısıl özellikleri sıcak disk yöntemi ile ASTM ve EN standartlarına uygun olarak belirlenmiştir. Deneysel çalışmaların sonuçlarına göre kullanılan agreganın elde edilen betonun mukavemetini ve yoğunluğunu düşürdüğü, buna karşı ısı ve ses yalıtım özelliğini yüksek oranda arttırdığı görülmüştür. Bu çalışmada dünyada ve ülkemizdeki endüstriyel atık ürünlerinin mühendislik çalışmalarındaki sonuçları derlenerek yorumlanmıştır.
Experimental investigation of solar stills integrated with solar water heating collectors
(Türk Isı Bilimi ve Tekniği Derneği, 2017-10-31) Argunhan, Zeki; El, Emin; Yıldız, Cengiz; Çakmak, Gülşah
Solar still is a more practical way of obtaining clean water. In this study, we aimed to improve the efficiency of solar still systems and obtain distilled water at the same time. For this purpose, 5 different solar still systems were designed. Type 1; conventional solar still, Type 2; conventional solar still integrated with solar water heating collector and run via natural convection, Type 3; conventional solar still integrated with solar water heating collector and tubular heat exchanger and run via natural convection, Type 4; conventional solar still placed with plate heat exchanger and integrated with solar water heating collector and run via natural convection, Type 5; conventional solar still placed with plate heat exchanger and integrated with solar water heating collector and run via forced convection. In this study, the experiments were carried out on the parameters influencing the performance, the amount of distilled water obtained, and the efficiency of experiment settings designed in different types; and finally the results were presented. The amount of distilled water and efficiency of conventional solar still were 2389 ml and 51.47%, respectively. Maximum total amount of water and efficiency from natural convection systems were obtained from Type 4, and the values calculated were found as to be 5788 ml and 55.91%. Maximum amount of distilled water and the efficiency were obtained by utilizing forced convection system were found as to be 6068 ml and 58.99%, respectively.
Friction welding of dissimilar AISI 304 and AISI 8640 steels
(European Journal of Technique (EJT), 2016-08-01) Batı, Serkan; Kılıç, Musa; Kırık, İhsan
This study investigates the joinability of AISI 8640 heat treatable steel and AISI 304 austenitic stainless steel combined with friction welding. These steels have completely different properties and widely used in industrial applications. Welding is applied on steels with the parameters of 1800 rev/min turning speed, 50 MPa friction pressure and 2, 4, 6, 8 and 10 sec friction time by using continuously driven friction welding machine. After the welding process, tensile and hardness testing applied to determine tensile and hardness strength of welded samples. Additionally, in order to determine the microstructural features, research using the optical microscope, scanning electron microscope (SEM) with Energy-dispersive Xray spectroscopy (EDS) analysis tests were done. According to the information derived from the results, AISI 304 and AISI 8640 steels joined with friction welding without any problem
Production of Intermetallic FGM
(Middle East Journal of Technic (MEJT), 2017-01) Batı, Serkan; Kılıç, Musa; Kırık, İhsan
NiAl and NiTi intermetallic materials are among advanced technology materials that have outstanding mechanical and physical properties for high temperature applications. Particularly, creep resistance, low density and high hardness properties stand out in such intermetallics. It is known that Ni-Al intermetallics are commonly used in various application fields with the addition of Ti for improving properties there of (in terms of low density, high hardness and shear strength) in the produced intermetallics. In this study, with different features -325 mesh Al, Ni and Ti powders are mixed to form NiTi, Ni3Al and NiAl in atomic ratio. Sintering process was used in this study by adding different amounts of powder mixture. The mixed powders were pressed at a pressure of 100 MPa in a metal die at room temperature. Three important intermetallic compounds were produced by SHS method, by using different process parameters to obtain functionally-graded materials having different features of NiAl, Ni3Al and NiTi alloys. Analyses were conducted metallographically on the samples after producing, face propagation were calculated and hardness were determined
Microstructure and mechanical properties of armor 500/AISI2205 steel joint by friction welding
(Journals & Books, 2017-08) Batı, Serkan; Kırık, İhsan; Sarsılmaz, Furkan
This paper discussed the properties of friction welded joint of Armor 500 steel and duplex (ferritic/austenitic) steel AISI 2205 and compared the properties of weld at different welding parameters. The experimental study was conducted with the welding parameters such as friction pressure and friction time. The experimental results indicated that armor 500 steel could be joined to AISI 2205 steel using the traditional friction welding technique. The processed joints were tested through axial tension test. In addition, the highest tensile strength, which is 1020 MPa is obtained when friction time is 8 s and friction pressure is 80 MPa. The microstructures of the alloys and fracture surfaces were examined by optical and scanning electron microscopy. Experimental results indicate that microstructural and mechanical properties are significantly affected by changing welding parameters within the chosen range of conditions.

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