Abdulkadir Yaşar - Academia.edu (original) (raw)

Papers by Abdulkadir Yaşar

Çukurova Üniversitesi Mühendislik Fakültesi Dergisi

Makine parçaları korozyon ve aşınma gibi malzeme yüzeylerinde hasara neden olan çeşitli etkilere ... more Makine parçaları korozyon ve aşınma gibi malzeme yüzeylerinde hasara neden olan çeşitli etkilere maruz kalmaktadır. Malzeme yüzeylerinin bu zararlı etkilerden korunması için çeşitli ve etkili yöntemler bulunmaktadır. Elektrokimyasal kaplama bu yöntemlerden en çok tercih edilenlerden bir tanesidir. Bu çalışmada, Ni-B alaşımı ana yapısı titanyum karbür (TiC) takviye parçacıkları ile desteklenerek, sanayide kullanımı çok tercih edilen AISI 304 kalite paslanmaz çelik üzerine elektrokimyasal depolama metodu ile kaplanmıştır. Elde edilen bu kaplamaların korozyon dayanımları elektrokimyasal empedans spektroskopisi (EES) yöntemi ile analiz edilmiştir. Mukayese yapmak amacıyla paslanmaz çelik altlığın korozyon direncinin yanı sıra, saf nikel ve Ni-B alaşım kaplamalarda üretilmiş ve korozyon direnci incelenmiştir. Elde edilen sonuçlara göre, Ni-B/TiC nanokompozit kaplamaların Nyquist eğrilerinin, paslanmaz çelik, saf nikel ve Ni-B alaşıma göre çok daha kapsayıcı ve geniş görünümlü olduğu tesp...

International Journal of Scientific and Technological Research, 2015

The most prominent challenge in today’s vehicle industry is how to cope with the accretive demand... more The most prominent challenge in today’s vehicle industry is how to cope with the accretive demand for ever higher performance, longer life, safety and lower weight of components so that fuel economy requirements can be achieved at realistic cost levels. Chassis of a truck is the skeleton for a vehicle providing structural strength and mounting points for other components. In this study, a truck ladder chassis was 3D- modelled using Computer Aided Designed (CAD) method via CATIA TM software. Finite Element Analyses (FEA) were conducted on the truck ladder chassis by varying materials such as AISI 1006 Structural Steel and ASTM Class 30 Cast Iron using ANSYS software. The analyses were executed by considering various materials, number of wheels, type of profiles, and supports used. The optimum levels of the control factors for minimizing the deformation using S/N rates were determined for a wheel size of 6x4, I profile, and supports used. The optimization was finally carried out using Taguchi method in the Minitab software. Keywords: Vehicle Ladder Chassis, Computer Aided Design, FEA, Taguchi method.

Tarım Makinaları Bilimi Dergisi, Aug 1, 2014

A suspension system or shock absorber is a mechanical device designed to smooth out or damp shock... more A suspension system or shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. In a vehicle, it reduces the effect of traveling over rough ground, leading to improved ride quality, and increase in comfort due to substantially reduced amplitude of disturbances. The design of spring in suspension system is very important. In this study, a shock absorber is designed and a 3D model is created using CATIA. The model is also modified by changing the wire diameter (thickness) of the spring. Structural and modal analyses are conducted on the shock absorber by varying material as stainless steel and aluminum alloy using ANSYS. The analysis is executed by considering hydraulic oil density and loads, vehicle weight and 4 persons. Also, comparison models were created for two materials and hydraulic fluid to verify optimum material for spring and shock absorber. And, results were analyzed and optimized in the Minitab program by using Taguchi method.

DergiPark (Istanbul University), Aug 1, 2014

Biodiesel, which is an alternative to diesel fuel, is made from renewable biological sources such... more Biodiesel, which is an alternative to diesel fuel, is made from renewable biological sources such as vegetable oils and animal fats. It is biodegradable and nontoxic has low emission profiles and so is environmentally beneficial. In this study, the effects of different injection angles, compression ratios and different piston bowls (Pan and Mexican Hat) on the engine performance and emissions were investigated by using two different fuels which are standard diesel (D2) and SME B40(Soybean Oil Methyl Ester). Diesel-RK software was used for the simulation of an internal combustion engine. Simulation results include efficiency and power parameters as piston engine power, torque and specific fuel consumption and also ecological parameters as specific CO 2 and NO x emissions. The results showed that the best optimized combination was the Pan piston bowl shape with SME B40 fueled at 22:1 compression ratio and at 50 o injection angle.

It is utilized increasingly to use adhesive bonding in automotive industry to join structural com... more It is utilized increasingly to use adhesive bonding in automotive industry to join structural components of metallic materials. The aim of this experimental study is to extend the information available to the automotive design engineer and contribute the better understanding of how the various geometrical shaped of steel parts affect the adhesive bonding. In this study, different types of lap joints, such as butt, step butt, scarf, tubular lap, were used to determine the mechanical strength of SAE/AISI 1350 steel. It has been observed that the cylindrical geometries can be subject to more stress compared to square specimens generally and the geometries with both tensile and shear stress can stand more stress per unit compared with the specimens with only tensile stress.

Applied Biochemistry and Biotechnology, 1994

This study focused on the evaluation and testing of safflower seed oil methyl ester as a diesel f... more This study focused on the evaluation and testing of safflower seed oil methyl ester as a diesel fuel alternative. The kinematic viscosity and ASTM fuel properties of the methyl ester fuel were within the limits specified for Grade No.2-D diesel fuel. Engine tests were performed on a four-cylinder, direct-injection CI engine using methyl ester and reference diesel fuel; engine performance

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Dec 31, 2018

Selective Catalytic Reduction (SCR) is an emission control system used in diesel engines to reduc... more Selective Catalytic Reduction (SCR) is an emission control system used in diesel engines to reduce NO x emissions. In this study, synthesized of catalyst for SCR system was investigated as experimentally. For this purpose, silver nitrate (AgNO 3), niobium (V) chloride (NbCl 5) and tetra amine platinum (II) nitrate (Pt(NH 3) 4 (NO 3) 2) were used to coat the cordierite (2Al 2 O 3-5SiO 2-2MgO) structure with impregnation method. X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and Brunauer, Emmett, and Teller (BET) analyzes were carried out in order to determine the chemical and physical properties of the catalyst. Results showed that the coating materials penetrate the entire surface of the pores. It was also determined that the BET specific surface areas of the produced catalyst and cordierite are 0.2918 m 2 /g and 0.4568 m 2 /g, respectively. The reduction of surface area could be attributed to the increment of crystallization with chemical reactions occurred at the high sintering temperature. Besides, XRF analysis results demonstrated that content of Ag, Pt and Nb in the in the catalyst was found to be 3.67%, 0.19% and 0.12%, respectively, whereas Ag content in cordierite structure was 0.03%.

International Journal of Automotive Engineering and Technologies, Oct 11, 2017

Application of mathematical modelling and numerical methods is a key element of optimum vehicle i... more Application of mathematical modelling and numerical methods is a key element of optimum vehicle in this study, the effects of various materials, fillet radius and diameter of an engine valve on stress concentration error were investigated. Multiple regression analysis was employed to derive the predictive equations of the Von Mises Stress and displacement error achieved via experimental design and their results are found in ANSYS software. For this purpose, two materials as cast iron and aluminum, radius condition as with radius and without radius and also diameter with 5 and 6 mm considered as control factors. Optimal control factors for the stress concentration were determined by using Taguchi technique. Minimum von misses stress and displacement were obtained by means of ANSYS software. Confirmation experiments showed that Taguchi method precisely optimized the control parameters on stress concentration.

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Jun 1, 2014

Nowadays the world trends toward the non-conventional energy resources such as solar energy. The ... more Nowadays the world trends toward the non-conventional energy resources such as solar energy. The most advantage of solar energy compared to other forms of clean energy is that there is no environmental pollution. In this study, the current status, developments, future projections and applications of Concentrating Solar Power (CSP) technology in the world were presented. CSP technology, consisting of four main CSP technology families called as parabolic troughs, lineer frensel reflectors, solar towers and parabolic dishes was evaluated in terms of investment costs. As a result of this study, CSP is still under 1% within the total global installed renewable power capacity. However, a constant increase is observed in this percentage ratio day by day. Also, CSP has the advantage of relatively low cost thermal storage, compared to other renewable technologies.

An experimental research was conducted to evaluate the effects of n-butanol (normal butanol) addi... more An experimental research was conducted to evaluate the effects of n-butanol (normal butanol) addition to conventional diesel fuel and microalgae biodiesel (MB) blends on the performance and exhaust emissions of a diesel engine. Engine performance parameters and exhaust gas emissions such as nitrogen oxides, carbon monoxide were measured. It is revealed that; although n-butanol addition caused a slight reduction in torque and brake power values, the emission values of the engine were improved. Measured physical properties of n-butanol, MB and diesel blend (D70B20But10) satisfy EN 14214 standards. Therefore, n-butanol can be used as a very promising additive to diesel-microalgae biodiesel blends.

Recently, the usage of biodiesel as an alternative energy source instead of fossil-based fuels be... more Recently, the usage of biodiesel as an alternative energy source instead of fossil-based fuels becomes very popular because biodiesel is totally renewable and has more favorable combustion emission profiles except NO x emissions. Scientists are focusing on decreasing NO x emissions in compression ignition engines. In this paper, effects of different bowl geometries on biodiesel NO x emissions were theoretically studied in order to reach minimum NO x levels. Simulations were carried out with diesel No.2, soybean and rapeseed biodiesel fuels using the simulation software Diesel-rk. Seven different piston bowl type were used in the tests and datas were compared. Results showed that Hasselman, Pan and Mexican Hat bowl geometries concluded less NO x emissions then the other four. Air swirl velocities also showed that the bowl geometries were directly influence the NO x emissions by effecting in-cylinder combustion.

Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 2012

Bu calismada, duvar tipi bir split klimada evaporator filtrelerindeki ve kondenser serpantinlerin... more Bu calismada, duvar tipi bir split klimada evaporator filtrelerindeki ve kondenser serpantinlerindeki tikanikliginsistem performansi uzerindeki etkileri incelenmistir. Sayisal deger alinabilecek tarzda tasarlanan orijinal birklimada, evaporator filtreleri ve kondenser serpantinleri uzerinde kademeli sekilde tikaniklik olusturularaksistemin sicaklik, basinc, isil kapasite, guc ve isitma-sogutma etkinliklerindeki (COP) degisimlergozlemlenmistir. Elde edilen sonuclara gore, hava filtresi uzerindeki kirlenme nedeniyle evaporator filtresiuzerinde olusturulan tikanikligin %50 ve %100 duzeyinde gerceklesmesi durumunda, klima sisteminin sogutmaetkinligi (COP) sirasiyla %3,32 ve %11,19 oraninda azalmistir. Ayrica, kondenser serpantininde egilme, ezilmeve kirlenme gibi nedenlerle olusan tikanikligin %50 ve %100 duzeyinde olmasi durumunda klima sistemininsogutma etkinliginde (COP) sirasiyla %12,07 ve %47,38 oraninda azalma gorulmustur. Sonuclar, evaporatorfiltrelerinin, kondenser ve evaporator serpantin yuzey bakimlarinin duzenli sekilde yapilmasi geregini ortayacikarmaktadir. Bu suretle, duvar tipi split klimalarin daha az enerjiyle isitma ve sogutma islevini yerine getirmesive uzun yillar sorunsuz sekilde isletilmesi saglanacaktir.

Social Science Research Network, 2022

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Mar 31, 2020

Bu çalışmada, nikel esaslı alaşım ve nanokompozit kaplamalar elektrokimyasal depolama metodu ile ... more Bu çalışmada, nikel esaslı alaşım ve nanokompozit kaplamalar elektrokimyasal depolama metodu ile paslanmaz çelik altlık üzerine üretilmiştir. Watts tipi nikel banyosuna bor kaynağı olarak trimetilamin boran (TMAB) ilave edilerek NiB alaşım kaplama elde edilmiş, daha sonra buna ilave olarak banyoya titanyum diborür (TiB 2) seramik nano parçacıkları ilave edilerek nanokompozit kaplama elde edilmiştir. Elektrolit bileşenlerinin kaplama özelliklerine etkilerini incelemek amacıyla elektrokimyasal, mikrosertlik, korozyon dayanımı ve yüzey morfolojileri açısından analizler yapılmıştır. Yapılan incelemeler sonucunda her banyo bileşeninin morfoloji, sertlik ve korozyon dayanımı gibi özellikleri ciddi miktarda etkilediği görülmektedir. Genel olarak yüzey morfolojiler pürüzsüz olmakla birlikte, nanokompozit kaplamanın yüzeyinin daha kaba olduğu optik resimlerden anlaşılmaktadır. Ana yapıya bor elementi ilavesi mikro sertliği yaklaşık %38 oranında artırırken, TiB 2 takviyesiyle birlikte saf nikele göre %140, NiB alaşımına göre %75 oranında iyileşme olmasına sebep olmuştur. Bor takviyesi korozyon dayanımını azaltırken, TiB 2 takviyesi korozyon dayanımında artışa neden olmuştur.

International Journal of Exergy, 2016

This work presents an experimental investigation on energy and exergy performance characteristics... more This work presents an experimental investigation on energy and exergy performance characteristics of a typical residential split air conditioning system. Analyses are performed for different atmospheric temperatures. On the basis of experimental data coefficient of performances (COP), exergy efficiencies (ψ) and exergy destructions (Ėx dest) of whole system and its each subunits are evaluated. The results also demonstrate that the atmospheric temperature (T atm) rise affects the system performance as well as its performance of components substantially. The values of Ėx dest in the compressor and capillary tube increase with an increase of T atm but the values of Ėx dest in the condenser and evaporator decrease with an increase of T atm. When T atm is risen from 20°C to 46°C; it is determined that power consumption comp () W and Ėx dest of the air conditioning system are enhanced by 47.1% and 24.5%, respectively, but ψ is reduced by 38.8%.

International Journal of Exergy, 2016

In this paper, exergy analysis was implemented to improve the intercity bus airconditioning (AC) ... more In this paper, exergy analysis was implemented to improve the intercity bus airconditioning (AC) system design. Firstly, an inter-city bus with a passenger capacity of 56 people was selected and then its hourly cooling load 446 E. Tosun et al. capacity was determined with the help of cooling load hourly analysis program (HAP). Analyses were performed for different air mixing ratios (MRs) and seasons. Coefficient of performance (COP), exergy efficiency (ψ) and exergy destructions (Ėx dest) of whole system and its each sub-units were evaluated. Results demonstrated that the atmospheric air temperature and air MR substantially affect the inter-city bus AC systems' performance. According to the results obtained for July, when air MR is 0.5, maximum exergy destruction value was calculated as 6.96 kW at compressor. Exergy destruction values were computed as 2.78, 2.61 and 0.99 kW for evaporator, condenser and expansion valve, respectively.

International Journal of Green Energy, Jul 20, 2017

The operation of modern horizontal axis wind turbine (HAWT) includes a number of important factor... more The operation of modern horizontal axis wind turbine (HAWT) includes a number of important factors, such as wind power (P), power coefficient (C P), axial flow induction factor (a), rotational speed (Ω), tip speed ratio (λ), and thrust force (T). The aerodynamic qualities of these aspects are evaluated and discussed in this study. For this aim, the measured data are obtained from the Sebenoba Wind Energy Power Plant (WEPP) which is located in the Sebenoba region in Hatay, Turkey, and a wind turbine with a capacity of 2 MW is selected for evaluation. According to the results obtained, the maximum turbine power output, maximum power coefficient, maximum axial flow induction factor, maximum thrust force, optimum rotational speed, probability density of optimum rotational speed and optimum tip speed ratio are found to be 2 MW, 30%, 0.091, 140 kN, 16.11 rpm, 46.76 % and 7, respectively. This study has revealed that wind turbines must work under optimum conditions in order to extract as much energy as possible for approaching the ideal limit.

Çukurova Üniversitesi Mühendislik Fakültesi Dergisi

Makine parçaları korozyon ve aşınma gibi malzeme yüzeylerinde hasara neden olan çeşitli etkilere ... more Makine parçaları korozyon ve aşınma gibi malzeme yüzeylerinde hasara neden olan çeşitli etkilere maruz kalmaktadır. Malzeme yüzeylerinin bu zararlı etkilerden korunması için çeşitli ve etkili yöntemler bulunmaktadır. Elektrokimyasal kaplama bu yöntemlerden en çok tercih edilenlerden bir tanesidir. Bu çalışmada, Ni-B alaşımı ana yapısı titanyum karbür (TiC) takviye parçacıkları ile desteklenerek, sanayide kullanımı çok tercih edilen AISI 304 kalite paslanmaz çelik üzerine elektrokimyasal depolama metodu ile kaplanmıştır. Elde edilen bu kaplamaların korozyon dayanımları elektrokimyasal empedans spektroskopisi (EES) yöntemi ile analiz edilmiştir. Mukayese yapmak amacıyla paslanmaz çelik altlığın korozyon direncinin yanı sıra, saf nikel ve Ni-B alaşım kaplamalarda üretilmiş ve korozyon direnci incelenmiştir. Elde edilen sonuçlara göre, Ni-B/TiC nanokompozit kaplamaların Nyquist eğrilerinin, paslanmaz çelik, saf nikel ve Ni-B alaşıma göre çok daha kapsayıcı ve geniş görünümlü olduğu tesp...

International Journal of Scientific and Technological Research, 2015

The most prominent challenge in today’s vehicle industry is how to cope with the accretive demand... more The most prominent challenge in today’s vehicle industry is how to cope with the accretive demand for ever higher performance, longer life, safety and lower weight of components so that fuel economy requirements can be achieved at realistic cost levels. Chassis of a truck is the skeleton for a vehicle providing structural strength and mounting points for other components. In this study, a truck ladder chassis was 3D- modelled using Computer Aided Designed (CAD) method via CATIA TM software. Finite Element Analyses (FEA) were conducted on the truck ladder chassis by varying materials such as AISI 1006 Structural Steel and ASTM Class 30 Cast Iron using ANSYS software. The analyses were executed by considering various materials, number of wheels, type of profiles, and supports used. The optimum levels of the control factors for minimizing the deformation using S/N rates were determined for a wheel size of 6x4, I profile, and supports used. The optimization was finally carried out using Taguchi method in the Minitab software. Keywords: Vehicle Ladder Chassis, Computer Aided Design, FEA, Taguchi method.

Tarım Makinaları Bilimi Dergisi, Aug 1, 2014

A suspension system or shock absorber is a mechanical device designed to smooth out or damp shock... more A suspension system or shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. In a vehicle, it reduces the effect of traveling over rough ground, leading to improved ride quality, and increase in comfort due to substantially reduced amplitude of disturbances. The design of spring in suspension system is very important. In this study, a shock absorber is designed and a 3D model is created using CATIA. The model is also modified by changing the wire diameter (thickness) of the spring. Structural and modal analyses are conducted on the shock absorber by varying material as stainless steel and aluminum alloy using ANSYS. The analysis is executed by considering hydraulic oil density and loads, vehicle weight and 4 persons. Also, comparison models were created for two materials and hydraulic fluid to verify optimum material for spring and shock absorber. And, results were analyzed and optimized in the Minitab program by using Taguchi method.

DergiPark (Istanbul University), Aug 1, 2014

Biodiesel, which is an alternative to diesel fuel, is made from renewable biological sources such... more Biodiesel, which is an alternative to diesel fuel, is made from renewable biological sources such as vegetable oils and animal fats. It is biodegradable and nontoxic has low emission profiles and so is environmentally beneficial. In this study, the effects of different injection angles, compression ratios and different piston bowls (Pan and Mexican Hat) on the engine performance and emissions were investigated by using two different fuels which are standard diesel (D2) and SME B40(Soybean Oil Methyl Ester). Diesel-RK software was used for the simulation of an internal combustion engine. Simulation results include efficiency and power parameters as piston engine power, torque and specific fuel consumption and also ecological parameters as specific CO 2 and NO x emissions. The results showed that the best optimized combination was the Pan piston bowl shape with SME B40 fueled at 22:1 compression ratio and at 50 o injection angle.

It is utilized increasingly to use adhesive bonding in automotive industry to join structural com... more It is utilized increasingly to use adhesive bonding in automotive industry to join structural components of metallic materials. The aim of this experimental study is to extend the information available to the automotive design engineer and contribute the better understanding of how the various geometrical shaped of steel parts affect the adhesive bonding. In this study, different types of lap joints, such as butt, step butt, scarf, tubular lap, were used to determine the mechanical strength of SAE/AISI 1350 steel. It has been observed that the cylindrical geometries can be subject to more stress compared to square specimens generally and the geometries with both tensile and shear stress can stand more stress per unit compared with the specimens with only tensile stress.

Applied Biochemistry and Biotechnology, 1994

This study focused on the evaluation and testing of safflower seed oil methyl ester as a diesel f... more This study focused on the evaluation and testing of safflower seed oil methyl ester as a diesel fuel alternative. The kinematic viscosity and ASTM fuel properties of the methyl ester fuel were within the limits specified for Grade No.2-D diesel fuel. Engine tests were performed on a four-cylinder, direct-injection CI engine using methyl ester and reference diesel fuel; engine performance

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Dec 31, 2018

Selective Catalytic Reduction (SCR) is an emission control system used in diesel engines to reduc... more Selective Catalytic Reduction (SCR) is an emission control system used in diesel engines to reduce NO x emissions. In this study, synthesized of catalyst for SCR system was investigated as experimentally. For this purpose, silver nitrate (AgNO 3), niobium (V) chloride (NbCl 5) and tetra amine platinum (II) nitrate (Pt(NH 3) 4 (NO 3) 2) were used to coat the cordierite (2Al 2 O 3-5SiO 2-2MgO) structure with impregnation method. X-ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and Brunauer, Emmett, and Teller (BET) analyzes were carried out in order to determine the chemical and physical properties of the catalyst. Results showed that the coating materials penetrate the entire surface of the pores. It was also determined that the BET specific surface areas of the produced catalyst and cordierite are 0.2918 m 2 /g and 0.4568 m 2 /g, respectively. The reduction of surface area could be attributed to the increment of crystallization with chemical reactions occurred at the high sintering temperature. Besides, XRF analysis results demonstrated that content of Ag, Pt and Nb in the in the catalyst was found to be 3.67%, 0.19% and 0.12%, respectively, whereas Ag content in cordierite structure was 0.03%.

International Journal of Automotive Engineering and Technologies, Oct 11, 2017

Application of mathematical modelling and numerical methods is a key element of optimum vehicle i... more Application of mathematical modelling and numerical methods is a key element of optimum vehicle in this study, the effects of various materials, fillet radius and diameter of an engine valve on stress concentration error were investigated. Multiple regression analysis was employed to derive the predictive equations of the Von Mises Stress and displacement error achieved via experimental design and their results are found in ANSYS software. For this purpose, two materials as cast iron and aluminum, radius condition as with radius and without radius and also diameter with 5 and 6 mm considered as control factors. Optimal control factors for the stress concentration were determined by using Taguchi technique. Minimum von misses stress and displacement were obtained by means of ANSYS software. Confirmation experiments showed that Taguchi method precisely optimized the control parameters on stress concentration.

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Jun 1, 2014

Nowadays the world trends toward the non-conventional energy resources such as solar energy. The ... more Nowadays the world trends toward the non-conventional energy resources such as solar energy. The most advantage of solar energy compared to other forms of clean energy is that there is no environmental pollution. In this study, the current status, developments, future projections and applications of Concentrating Solar Power (CSP) technology in the world were presented. CSP technology, consisting of four main CSP technology families called as parabolic troughs, lineer frensel reflectors, solar towers and parabolic dishes was evaluated in terms of investment costs. As a result of this study, CSP is still under 1% within the total global installed renewable power capacity. However, a constant increase is observed in this percentage ratio day by day. Also, CSP has the advantage of relatively low cost thermal storage, compared to other renewable technologies.

An experimental research was conducted to evaluate the effects of n-butanol (normal butanol) addi... more An experimental research was conducted to evaluate the effects of n-butanol (normal butanol) addition to conventional diesel fuel and microalgae biodiesel (MB) blends on the performance and exhaust emissions of a diesel engine. Engine performance parameters and exhaust gas emissions such as nitrogen oxides, carbon monoxide were measured. It is revealed that; although n-butanol addition caused a slight reduction in torque and brake power values, the emission values of the engine were improved. Measured physical properties of n-butanol, MB and diesel blend (D70B20But10) satisfy EN 14214 standards. Therefore, n-butanol can be used as a very promising additive to diesel-microalgae biodiesel blends.

Recently, the usage of biodiesel as an alternative energy source instead of fossil-based fuels be... more Recently, the usage of biodiesel as an alternative energy source instead of fossil-based fuels becomes very popular because biodiesel is totally renewable and has more favorable combustion emission profiles except NO x emissions. Scientists are focusing on decreasing NO x emissions in compression ignition engines. In this paper, effects of different bowl geometries on biodiesel NO x emissions were theoretically studied in order to reach minimum NO x levels. Simulations were carried out with diesel No.2, soybean and rapeseed biodiesel fuels using the simulation software Diesel-rk. Seven different piston bowl type were used in the tests and datas were compared. Results showed that Hasselman, Pan and Mexican Hat bowl geometries concluded less NO x emissions then the other four. Air swirl velocities also showed that the bowl geometries were directly influence the NO x emissions by effecting in-cylinder combustion.

Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 2012

Bu calismada, duvar tipi bir split klimada evaporator filtrelerindeki ve kondenser serpantinlerin... more Bu calismada, duvar tipi bir split klimada evaporator filtrelerindeki ve kondenser serpantinlerindeki tikanikliginsistem performansi uzerindeki etkileri incelenmistir. Sayisal deger alinabilecek tarzda tasarlanan orijinal birklimada, evaporator filtreleri ve kondenser serpantinleri uzerinde kademeli sekilde tikaniklik olusturularaksistemin sicaklik, basinc, isil kapasite, guc ve isitma-sogutma etkinliklerindeki (COP) degisimlergozlemlenmistir. Elde edilen sonuclara gore, hava filtresi uzerindeki kirlenme nedeniyle evaporator filtresiuzerinde olusturulan tikanikligin %50 ve %100 duzeyinde gerceklesmesi durumunda, klima sisteminin sogutmaetkinligi (COP) sirasiyla %3,32 ve %11,19 oraninda azalmistir. Ayrica, kondenser serpantininde egilme, ezilmeve kirlenme gibi nedenlerle olusan tikanikligin %50 ve %100 duzeyinde olmasi durumunda klima sistemininsogutma etkinliginde (COP) sirasiyla %12,07 ve %47,38 oraninda azalma gorulmustur. Sonuclar, evaporatorfiltrelerinin, kondenser ve evaporator serpantin yuzey bakimlarinin duzenli sekilde yapilmasi geregini ortayacikarmaktadir. Bu suretle, duvar tipi split klimalarin daha az enerjiyle isitma ve sogutma islevini yerine getirmesive uzun yillar sorunsuz sekilde isletilmesi saglanacaktir.

Social Science Research Network, 2022

Çukurova Üniversitesi Mühendislik Mimarlık Fakültesi dergisi, Mar 31, 2020

Bu çalışmada, nikel esaslı alaşım ve nanokompozit kaplamalar elektrokimyasal depolama metodu ile ... more Bu çalışmada, nikel esaslı alaşım ve nanokompozit kaplamalar elektrokimyasal depolama metodu ile paslanmaz çelik altlık üzerine üretilmiştir. Watts tipi nikel banyosuna bor kaynağı olarak trimetilamin boran (TMAB) ilave edilerek NiB alaşım kaplama elde edilmiş, daha sonra buna ilave olarak banyoya titanyum diborür (TiB 2) seramik nano parçacıkları ilave edilerek nanokompozit kaplama elde edilmiştir. Elektrolit bileşenlerinin kaplama özelliklerine etkilerini incelemek amacıyla elektrokimyasal, mikrosertlik, korozyon dayanımı ve yüzey morfolojileri açısından analizler yapılmıştır. Yapılan incelemeler sonucunda her banyo bileşeninin morfoloji, sertlik ve korozyon dayanımı gibi özellikleri ciddi miktarda etkilediği görülmektedir. Genel olarak yüzey morfolojiler pürüzsüz olmakla birlikte, nanokompozit kaplamanın yüzeyinin daha kaba olduğu optik resimlerden anlaşılmaktadır. Ana yapıya bor elementi ilavesi mikro sertliği yaklaşık %38 oranında artırırken, TiB 2 takviyesiyle birlikte saf nikele göre %140, NiB alaşımına göre %75 oranında iyileşme olmasına sebep olmuştur. Bor takviyesi korozyon dayanımını azaltırken, TiB 2 takviyesi korozyon dayanımında artışa neden olmuştur.

International Journal of Exergy, 2016

This work presents an experimental investigation on energy and exergy performance characteristics... more This work presents an experimental investigation on energy and exergy performance characteristics of a typical residential split air conditioning system. Analyses are performed for different atmospheric temperatures. On the basis of experimental data coefficient of performances (COP), exergy efficiencies (ψ) and exergy destructions (Ėx dest) of whole system and its each subunits are evaluated. The results also demonstrate that the atmospheric temperature (T atm) rise affects the system performance as well as its performance of components substantially. The values of Ėx dest in the compressor and capillary tube increase with an increase of T atm but the values of Ėx dest in the condenser and evaporator decrease with an increase of T atm. When T atm is risen from 20°C to 46°C; it is determined that power consumption comp () W and Ėx dest of the air conditioning system are enhanced by 47.1% and 24.5%, respectively, but ψ is reduced by 38.8%.

International Journal of Exergy, 2016

In this paper, exergy analysis was implemented to improve the intercity bus airconditioning (AC) ... more In this paper, exergy analysis was implemented to improve the intercity bus airconditioning (AC) system design. Firstly, an inter-city bus with a passenger capacity of 56 people was selected and then its hourly cooling load 446 E. Tosun et al. capacity was determined with the help of cooling load hourly analysis program (HAP). Analyses were performed for different air mixing ratios (MRs) and seasons. Coefficient of performance (COP), exergy efficiency (ψ) and exergy destructions (Ėx dest) of whole system and its each sub-units were evaluated. Results demonstrated that the atmospheric air temperature and air MR substantially affect the inter-city bus AC systems' performance. According to the results obtained for July, when air MR is 0.5, maximum exergy destruction value was calculated as 6.96 kW at compressor. Exergy destruction values were computed as 2.78, 2.61 and 0.99 kW for evaporator, condenser and expansion valve, respectively.

International Journal of Green Energy, Jul 20, 2017

The operation of modern horizontal axis wind turbine (HAWT) includes a number of important factor... more The operation of modern horizontal axis wind turbine (HAWT) includes a number of important factors, such as wind power (P), power coefficient (C P), axial flow induction factor (a), rotational speed (Ω), tip speed ratio (λ), and thrust force (T). The aerodynamic qualities of these aspects are evaluated and discussed in this study. For this aim, the measured data are obtained from the Sebenoba Wind Energy Power Plant (WEPP) which is located in the Sebenoba region in Hatay, Turkey, and a wind turbine with a capacity of 2 MW is selected for evaluation. According to the results obtained, the maximum turbine power output, maximum power coefficient, maximum axial flow induction factor, maximum thrust force, optimum rotational speed, probability density of optimum rotational speed and optimum tip speed ratio are found to be 2 MW, 30%, 0.091, 140 kN, 16.11 rpm, 46.76 % and 7, respectively. This study has revealed that wind turbines must work under optimum conditions in order to extract as much energy as possible for approaching the ideal limit.