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Öğe Şanlıurfa ilinde yatay yüzeye gelen anlık global güneş ışınımının modellenmesi(Dicle Üniversitesi, 2019-03-15) Karakaya, Hakan; Kallioğlu, Mehmet Ali; Avcı, Ali Serkan; Ercan, UmutBu çalışma ile Şanlıurfa ilinin iklim özellikleri ve topografik yapısı göz önüne alınarak yatay düzleme gelen aylık ortalama günlük global güneş radyasyonunun tespit edilebilmesi için literatürde yer alan 5 farklı model incelenmiştir. Sonuçlar istatistiksel karşılaştırma metotları, belirlilik katsayısı (R²), ortalama yüzde hata (MPE), sapma hatası (MBE), ortalama mutlak hata yüzdesi (MAPE), bağıl hata karesi (SSRE), bağıl standart hata (RSE), ortalama karekök hatası (RMSE), bağıl hata yüzdesi (e) ve t-istatistik (t-sat) ile olmak üzere dokuz farklı istatistik yöntemi ile karşılaştırılmıştır. Şanlıurfa ili için en uygun yaklaşım için bir sonuç verilmiştir. İstatistiksel hata sonuçlarına göre Cheegar ve Chibani Modeli yatay düzleme gelen global güneş ışınımı için Şanlıurfa ilinde kullanılacak en uygun model olarak belirlenmiştir. Sonuç olarak Şanlıurfa ili toplam güneş radyasyonu tahmini için polinom modelin tercih edilmesi önerilmiştir. Bu model verilerine göre Şanlıurfa ili için yıllık güneş enerjisi potansiyeli 4332,020 W/m2 /ay olarak belirlenmiştirÖğe Optimum insulation thickness assessment of different insulation materials for mid-latitude steppe and desert climate (BSH) region of India(Journals & Books, 2021-01) Kallioğlu, Mehmet Ali; Sharma, Ashutosh; Chinnasamy, Veerakumar; Chauhan, Ranchan; Singh, TejOne of the most effective techniques that is used for energy wastage in buildings is heat insulation. It is possible due to this application to minimize the fuel quantity and accordingly tolerate toxic emissions by finding the optimum point that gives the maximum efficiency. This study was conducted for Jaipur province in Indian climate geography. Climatic characteristics of the region are Mid-Latitude Steppe and Desert Climate (Bsh). Energy need and heat losses in exterior wall were determined by accepting cooling degree day value as T > 24 °C. Optimum insulation thickness, payback period, annual return and annual return rate for XPS and EPS of two different insulating materials respectively are 0.0383–0.0731, 2.35–1.79, 10.95–12.92, 46.84–37.25.Öğe Energy efficiency and thermal comfort analysis of traditional Diyarbakır inn(IJSER, 2019-09) Kallioğlu, Mehmet Ali; Yılmaz, Adem; Ünvar, Sinan; Beştaş, BilalThe traditional structures of Diyarbakır is reflect centuries of Mesopotamian culture interms of planning. Beside the walls of Diyarbakır, many buildings and traditional houseswere built with the most suitable materials and components depending on the climaticcharacteristics. It is easy to recycle to the environment because it is made of naturalmaterials and the design in which it conforms to the climatic and geographical structureof the environment in which it is located. In addition, it accommodates ecological andsustainable design criteria with its structure providing comfortable indoor environmentsthat can heat and cool without requiring additional measures. Nowadays, energy efficiencyand thermal comfort analyzes of these designs have been made with the engineeringsimulation program Autodesk Ecotect Analysis. In this study, thermal analysis and solarintensity of Sülüklü Han which was built in 1680 in different days, months and seasonswere investigated. National (BEPY) and international (ASHRAE) standards were evaluatedand simulated as a result of the simulations. Because fossil fuels have come to the end.With this study, energy efficiency of traditional buildings will be examined and energyefficiency will be provided for new buildings. Thus, maximum utilization of solar energy willbe achieved and energy saving will be achieved. title.Öğe A review of phase change materials (PCMs) for thermal storage in solar air heating systems(Journals & Books, 2021-01) Kallioğlu, Mehmet Ali; Sharma, Ashutosh; Chauhan, Ranchan; Chinnasamy, Veerakumar; Singh, TejThe surging energy requirements and greenhouse gas (GHG) emission have directed the research towards the utilization of renewable energy sources especially solar energy. Most of the energy part in domestic and commercial consumption is utilized for air heating and drying which can be improved significantly by utilizing solar air heating applications. The main drawback associated with the solar air heating system (SAHS) is the fluctuation in the availability of solar radiations which can be mitigated by a greater extent with the help of thermal storage. Phase change materials (PCMs) are generally utilized for latent heat storage. The present study reviews the various PCMs utilized in thermal storage with SAHS. Numerous types of PCM materials, their properties and applications in solar air heating system have been reviewed. Heat transfer characteristics enhancement techniques like encapsulation, extended surfaces and conductive particle dispersion have also been studied. The air conditioning demands in the future could be significantly mitigated by utilizing these materials.Öğe Creating the optimum panel inclination angles of the southern aegean region(International Journal of Advances in Science Engineering and Technology, 2018-01) Karakaya, Hakan; Ercan, Umut; Kallioğlu, Mehmet Ali; Avcı, Ali Serkan; Genç, ÖmerValues that are used in solar energy applications are usually calculated by data for radiation reaching a horizontal plane. In order to achieve maximum efficiency in solar energy, panels must be at a suitable angle and position. This study determined monthly optimum panel angles for the Southern Aegean Region (Muğla) in Turkey and created three different correlations. In an annual course (January-December), panel angles varied in the order of 590 , 490 , 380 , 200 , 50 , 00 , 00 , 150 , 320 , 490 , 590 and 610 . The average annual panel inclination angle was 32.250 , and in the case of changing the angles monthly, the annual efficiency increased by 17.03% in comparison to horizontal position and reached the average annual radiation value of 5949 W/m2 -year. The best estimation model developed for the region was in the form of β . = 0,0002(δ) ଷ − 0,0092(δ) ଶ − 1,4379(δ) + 34,72. The statistical analysis values were R2 (0.9973), MBE (0.0031), RMSE (1.22) and t-sat (0.0085), while they successfully corresponded to the panel inclination values.Öğe Empirical calculation of the optimal tilt angle for solar collectors in northern hemisphere(Taylor & Francis, 2020-03) Karakaya, Hakan; Kallioğlu, Mehmet Ali; Durmuş, Aydın; Yılmaz, AdemPanel tilt angles (0°–90°) need to be in a proper position and location to get maximum productivity from solar energy. Values used in solar energy applications are generally computed by (global, diffuse, and direct) variation on horizontal surfaces calculated using isotropic sky and a mean albedo method. Being parallel to the available literature concerning such applications, this study focuses on the optimum solar panel angle. In this study, optimum solar panel angle value by months was determined for three sample provinces (Antalya, Kayseri, and Trabzon) first and North Hemisphere then. Capacity calculation of sample provinces was performed based on monthly, seasonal, and annual angle values and horizontal situation. Monthly and annual optimum angle values for Northern Hemisphere by 1° increase for between the latitudes of 1° N and 65° N. While the panel angle is at the highest level in autumn and winter (November-December-January and February) in annual process, the lowest angle is observed in spring and summer (May-June-July-August). Several different mathematical models have been developed for the sample provinces and Northern Hemisphere. While the variable of 12 different models that were developed for provinces is the Declination (δ) coefficient, the variable of 7 different models that were developed Northern Hemisphere is the latitude (Ø). Regional values in literature with estimation results of models were analyzed based on NASA and PVGIS data color scale. There was created a possibility of comparison by aligning all the optimum solar panel angle values of related location via a scale whose values vary by 1 and 10. Moreover, all the models were verified by statistical analysis methods. R2 (determination coefficient) in 19 different estimation equations is pretty close or equal to 1. However, the best among them is Eq. 32 (0.9979) for sample provinces and Eq. (33) (1) for the Northern Hemisphere; developed models are less-than-stellar. Other statistical data of these equations are MBE (−0.0616), RMSE (1.1176), t-sat (0.1830), Bias (1). For Eq. (32); MBE (1.96), RMSE (2.75), t-sat (8.13), MPE % (3.98), MAPE (5.87), SSRE (0.27), and RSE (0.06) for Eq. (33). The statistical analyzes indicate that all regression models are applicable in Turkey and Northern Hemisphere. Developed all correlations are recommended for academic and industrial users.Öğe Empirical modeling between degree days and optimum insulation thickness for external wall(Taylor & Francis, 2020-03) Karakaya, Hakan; Kallioğlu, Mehmet Ali; Ercan, Umut; Avcı, Ali Serkan; Fidan, CihatInsulating is the most effective method that is used to save energy in buildings. Samples from cities from different climatic zones from TS 825 (Turkey) first. Optimum insulation thickness () analysis is based on two types of insulating and four different fuels (natural gas, coal, fuel oil and electric) of related cities. Cost accounts, payback period and CO2-SO2 emission calculations were performed based on these analyses. Second of all, the relationship between a number of degree day (NDD) and optimum insulation thickness () was developed by linear, quadratic and cubic correlations. Thirty different mathematical correlations based on different fuel types by using XPS and EPS insulating materials. Twenty-four of these models that were developed were generated peculiar to the fuel type; six of them were generated based on average insulation thickness. R2 values of related correlations are between 0.9989 most and 0.9952 at least as well as it is pretty close to (R ≤ 1) one value. The model among these models is the cubic mathematical model that gives the best average value. a = 0.0036, b = 5E-05, c = – 7E-09 and d = 6E-13 are the values for XPS material. Following values are for EPS material; a = 0.0028, b = 5E-13, c = – 7E-09 and d = 4E-05. R2 determination coefficient of both two equations is pretty close to 0.9989 and 1; the models obtained are less-than-stellar. Optimum insulation thickness of the area can be known based on the type of material via the number of degree day without the need for long analyses. According to the R2 values, the use of all models is recommended for academic and industrial users.Öğe Correlation formulation for optimum tilt angle for maximizing the solar radiation on solar collector in the Western Himalayan region(Journals & Books, 2021-01) Kallioğlu, Mehmet Ali; Sharma, Ashutosh; Awasthi, Anchal; Chauhan, Ranchan; Fekete, Gusztáv; Singh, TejSolar tracking devices are efficacious in maximizing solar irradiation collection. However, higher price makes these systems less frequently used. As an alternative, optimum tilt angle estimation has the advantage that it does not involve tracking cost expenditure. In this study, optimum tilt angles for different months have been computed for Hamirpur, Himachal Pradesh, India (L 31° 42′ N). Several mathematical models and statistical tools have been employed to forecast the monthly optimum tilt angles for the selected site. Different scenarios have been presented by considering five, four, three, and two annual adjustment models to increase the practical usage of the estimated optimum tilt angles. Additionally, cost-benefit analysis has also be performed on the PV panels. Based on the results, it has been concluded that model M − 11, with three annual adjustments, stipulates maximum benefits over the other models. This study can serve as fundamental guidance for setting up solar energy plants in this specified region with the highest efficiency.Öğe Environmental and economic analysis of optimum heat insulation thickness in energy saving(European Journal of Technique (EJT), 2016-08-01) Karakaya, Hakan; Kallioğlu, Mehmet Ali; Arca Batı, Zülal; Durmuş, AylaDeveloping technology and increasing population cause the natural energy resources rapidly. This has compulsorily forced the countries such as Turkey, which import almost all energy needs and use great deal of it in home heating, to save energy. It will provide benefits for users, indirectly the economy of the country, with saving obtained from insulation. One of the most effective methods attaining gain of energy is heat insulation. While heat insulation is carried out, by determining the optimum efficiency point, the amount of fuel used decreases, which leads to cost reduction and highest efficiency level. Therefore, it is possible to tolerate harmful emissions. In this study, optimum insulation thickness, total cost, energy saving, duration of pay-back and environmental analysis for heating were conducted in Diyarbakır by utilizing different fuel and insulation types. When extruded polystyrene (XPS) was used, average optimum thickness was 0,0675 (m), annual return was 62,165%, duration of pay back was 1,83 (years) and CO2 and SO2 emissions were 76% lesser. When expanded polystyrene (EPS) was used, the parameters such as average optimum thickness 0,0825 (m), annual return 73,06%, duration of pay back 1,245 (years) and CO2 and SO2 emissions 85% lesser.
