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In this study, single- and multi-rate electricity tariffs for a residence in Sivas province were compared. Consumption in the residence was determined by examining the 5-year electricity bills of the house calculated based on pricing for the single-rate electricity tariff and the cost was calculated based on pricing for the multi-rate electricity tariff. The calculations revealed that monthly electricity consumption in the residence ranged between 220 kWh and 280 kWh. If the current consumption is priced using a multi-rate tariff, the energy cost will be reduced by only 7%. Electricity consumption habits should be supported by awareness-raising programs, and peak and day time electricity demand should be reduced by shifting electricity consumption to night hours.

WOS: 000471701900007, This study shows the amount of energy savings to be achieved in electricity consumption if the current lighting system in the buildings of the Cumhuriyet University campus in Turkey is replaced with efficient lighting systems. In addition, environmental effects of energy savings are determined by calculating the amounts of CO2, SO2, NOx, CO emissions. The Life Cycle Cost (LCC) analysis is used to determine energy costs and payback periods. The calculations reveal that the use of three alternative lighting systems would lead to a substantial reduction in electricity consumption ranging between 16.5% and 40.5%, and that the payback periods of these alternative lighting systems vary between 1.9 and 5 years.

In the present study, it is aimed to calculate the effect of ice formation on different cylinder geometries placed in a rectangular cavity filled with water. For this aim Fluent package program was used to solve the flow domain numerically and temperature distribution and ice formation depending on time were illustrated. Water temperature in the cavity and cylinder surface temperature were assumed as 4, 8 and ?10 °C respectively and firstly temperature distribution, velocity vector, liquid fraction and ratio of Ai/Ac (formed ice area/cross sectional area of cylinder) were determined for cylinders with different placement in fixed volume. © 2016, Springer-Verlag Berlin Heidelberg., Firat University Scientific Research Projects Management Unit: M-491, The authors acknowledge the CUBAP (The Scientific Research Projects Council of Cumhuriyet University) for the financial support of the project M-491.

Birçok Avrupa ülkesinde ve Amerika 'da elektrik tarifeleri günün saatlerine göre değişkenlik göstermektedir. Soğutma yükünün maksimum olduğu gündüz saatlerinde elektrik pahalı, soğutma ihtiyacının duyulmadığı gece saatlerinde ise daha ucuzdur. Bu durum .soğıı enerjisinin, gece saatlerinde depo edilip gündüz saatlerinde ise soğutma ihtiyacını karşılamak için kullanılması fikrini ortaya çıkarmıştır. Bu çalışmada, içerisinde su bulunan dikdörtgensel bir soğıı depolama tankına yerleştirilen farklı geometrilerin, buz oluşumuna etkilerinin karşılaştırılması amaçlanmıştır. Ayrıca tank içeresindeki faz değişim malzemesi olan suyun, başlangıçta farklı sıcaklıklarda olmasının da katılaşmaya olan etkileri incelenmiştir. Bu amaçla FLUENT paket programı kullanılarak; akış alanının zamana bağlı sayısal çözümü yapılmıştır. Dikdörtgensel tank iki boyutlu olarak modellenmiş ve akış alanı simetrik olduğundan, analizler tankın yarısı için yapılmıştır. ank içerisindeki su sıcaklığı () ÜC ve 0C olarak alınıp, silindir yüzey sıcaklığı -10 ÜC kabul edilerek, farklı geometrilerdeki silindir modelleri için, Al,/A, oranı (Buz alanı kesit alanı), sıcaklık dağılımı ve sıvı oranları hesaplanmıştır. Elde edilen sonuçlarda, tüm modellemeler için 900 s, 1800 s, 3600 ve 7200 deki sıcaklık ve sıvı oranlarının dağılımları incelenmiştir. Ayrıca farklı silindir düzenlemelerinin katılaşma oranlarının (Ab/A,) zamanla değişimi de değerlendirilmiştir. Dairesel olan silindir, elips ve altıgen modellerinde katılaşma oranlarının birbirine oldukça yakın olduğu görülmüş, üçgensel ve kare gibi keskin köşeli modellerde ise daha az buz oluşumu gözlenmiştir. Bununla beraber düzenlemelerin her birinde; su sıcaklığının ÜC olması durumunda, katılaşma oranlarının daha büyük olduğu tespit edilmiştir., For the past few decades, the world ’s energy supply has not been keeping up with increasing demand. Burgeoning countries undergoing industrial reform are consuming an increasing amount of crude oil, coal and electricity, which has increased overall energy prices to an unprecedented level (Sönmez et al., 2009). Ice cool thermal energy storage systems are often classified as static or dynamic, according to the way ice is delivered to the storage tank. In dynamic systems, ice is produced outside the storage tank and removed from the ice-making surface continuously (Dinçer, 2002). In static systems, an ice-making pipe is installed in the storage tank where ice is formed and later melted. Ice-on-coil systems produce ice outside coil. The ice may be melted using either an external melting system, which melts ice from the outer side, or an internal melting system (Dinçer, 2002). Habeebullah (2007) investigated growth rate of ice on the outside of' cooled copper tubes. Ice formation around an isothermally cooled horizontal cylinder and eflect of' natural convection were studied by Cheng et al (1988). Fertelli et al. (2009) studied analytically and experimentally the solidification around the horizontal tube by considering fully developed velocity profile in the tube. Experiments are performed to investigate the effects of' diflerent heat transfer fluid inlet temperatures on ice formation around the tube. Finite volume method (FLUENT program) was used to solve solidification around cylinders placed in fixed volume as cylindrical, elliptical, hexagon, triangle, square geometry of cooled cylinder. Quadrilateral grid was usedfor simulation and/iner grid distribution was used near cylinder surfaces. Grid spacing increases awayfrom cylinder surfaces, with total of20000 to 25000 elements The‘following assumptions were made to simulate solidification around cylinders in fixed space: i) Flow is two dimensional, laminar and incompressible; Water as Newtonian fluid for phase changing material; ii) Unique thermal conductivities and specific heats (ks, k1, Cs, Cı) are considered/or solid and liquid phases; and iii) Efects of viscous dissipation and radiation are ignored. Validation studies of the present model shows that variations of area ratio (A), /A_,) match with experimental data in entire time range for solidification around single cylinder. To examine eflect of' different cooled cylinder geometries (cylindrical, elliptical, hexagon, triangle, square) in rectangular cavity on transient natural convection in water with density inversion, calculations were carried out for different initial water temperatures. All calculations were carried out under condition of transient natural convection in water with cooled tubes. Diameter of'tubes was taken (d, 0.0254 m), and tank heights was taken as 11d. Water temperature in tank an cylinder surface temperature were assumed as °C, 0C and -10 °C respectively. Natural convection is not observed at ,: 0C for all models and thermal stratification is not established in the storage tank. The water which was at 0C temperatures in the beginning was observed to have reached different temperature values at different points of the tank at the 900 s. At the end of this period, phase change was observed in the tank and the ice layer on the cylinders was reached to specific thickness. Thermal stratified region is established by warm water placing at the bottom of the tank and cold water placing at the top ofthe tank This situation can also be seenfrom the temperature contours at the 900 s. At 1800 and other durations, the cold water at the top was observed to be colder when the ice thickness was increased. More temperature decrements of accumulated water at the bottom were observed to have decreased more; and diflerent thermal layer was seen to have appeared in the following period. When the temperature distributions at the end of the 3600 and 7200 are analyzed, it can be seen that the water temperature has decreased up to ÜC at the whole part of the tank except the bottom part. For the solidification rate obtained for all models, in case the cylinders are cylindrical, elliptical and hexagonal, the model for the highest solidification rate is obtained in the case of cylindrical. It was found that when the cylinders are triangular and square models, the solidification is affected negatively and more formation of' ice is seen for circular models.

WOS: 000322206700008, In this study, the influence of different wall types (stone, brick, concrete and bims - which are usually used in building construction in Turkey) on the optimum insulation thicknesses, energy savings, and payback periods was evaluated for six different energy types: LPG, electricity, fuel oil, coal, natural gas, and geothermal energy. Four cities from different climate zones (Aydin, Trabzon, Malatya, and Sivas) were selected for the analysis which was carried out with two different insulation materials. Results showed that insulation thicknesses were determined between 0 - 0.179 m, with the amount of 0 - 235.053 $/m(2) of energy saving and 0 - 11.53 years of payback period depending on various fuel and wall types., Office of Scientific Research Projects of Cumhuriyet University [M457], The author, Ahmet Fertelli, would like to acknowledge the financial support of the Office of Scientific Research Projects of Cumhuriyet University for funding under the contract No: M457.

In the present study, it is proposed to investigate ice formation of natural convection and variously located cylinder arrangements in a cooling storage rectangular tank with filled water. For this purpose a Fluent package program was used to solve a flow domain with unsteady state conditions. Ice formation shapes and temperature distributions were shown. Water temperature in the tank and surface temperature of cylinders were taken as 4 oC and -10 oC respectively. Staggered and inline cylinder geometries were investigated for temperature distribution, velocity vectors and ratio of Aice/Acylinder (ice area/cylinder cross sectional area) by changing transversal and longitudinal spacing., Cilj ovog rada je istraživanje formiranja ledenog sloja prirodnom konvekcijom pri raličitim rasporedima cilindara u rashladnom spremniku punjenim vodom. Za tu je svrhu korišten programski paket FLUENT za rješavanje domene strujanja pri nestacionarnim uvjetima. Pokazani su oblici formiranja ledenog sloja i temperaturne raspodjele. Temperatura vode u spremniku i površinska temperatura cilindara bile su 4, odnosno -10 oC. Za šahovski i linijski raspored cilindara istraživan je raspored temperature, vektori brzina i omjer Aice/Acylinder (površina leda/površina poprečnog presjeka cijevi) u uzdužnom i poprečnom smjeru

Bu çalışmada soğu enerjisi depolamasında kullanılan yatay bir boru etrafındaki faz değişimi araştırılmıştır. Farklı ısı transfer akışkanı sıcaklıklarının buz oluşumuna etkisini incelemek için deneyler yapılmıştır. Test tankı içerisinde farklı noktalarda sıcaklıkların ölçülmesiyle, suyun aşırı soğuma sıcaklığı ve zamanı tespit edilmiştir. Deney süresince boru etrafındaki buz kalınlığı farklı eksenel pozisyonlarda ölçülmüş ve boru etrafındaki buz oluşumunu tespit edebilmek için bir matematik model oluşturulmuştur. Model basit bir model olmasına rağmen, deneysel sonuçlarla model sonuçlarının birbiri ile uyumlu olduğu görülmüştür., This paper investigates phase change phenomena around a horizontal tube during a cooling process of thermal storage. Experiments are performed to investigate the effects of different heat transfer fluid inlet temperatures on ice formation around the tube. Supercooling temperature and the time for the start of nucleation of water are observed by measuring the time variations of temperature profiles at various locations inside the test vessel. The thickness of the ice formed around the tube was measured at different axial positions along the tube during the experiments. A mathematical model to predict ice formation around the tube is proposed. Comparison of the results of the model with that of the experiments showed that the agreement between the two is acceptable, although the model is simple.

In the present study, heat transfer structures were investigated for thermal bridges on both intermediate floor beamed wall block and balcony extension intermediate floor beamed wall. Temperature and heat flux contours were obtained for all models in the case of internal and external insulation cases with different insulation thicknesses (Si = 3 cm, 5 cm and 7 cm). Results showed that high heat transfer rates were obtained in the region of heat bridges for all building models. However the heat transfer rate did not decrease on the heat bridge region in the case of internal insulation. The most appropriate insulation model was the external insulation case and it was also obviously determined that heat transfer rate decreased with increments of insulation thickness., U ovom radu istražuje se prijenos topline u toplinskim mostovima postavljenim na podovima međukatova i na balkonskim istakama. Određene su temperature i gustoće toplinskih tokova za sve modele za slučajeve vanjske i unutrašnje izolacije, s različitim debljinama izolacije (Si = 3 cm, 5 cm i 7 cm). Rezultati istraživanja su pokazali vrlo visoke vrijednosti toplinskih tokova u području toplinskih mostova kod svih ugradbenih modela. Doduše nije došlo do opadanja toplinskog toka u toplinskim mostovima u slučaju postavljanja unutrašnje izolacije. Puno se prikladnijim pokazao model u slučaju postavljanja vanjske izolacije i jasno je određeno da dolazi u tom slučaju do smanjenja toplinskog toka s povećavanjem debljine izolacije.