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Öğe Approximate solution of Drinfeld–Sokolov–Satsuma–Hirota (DSSH) equations by Residual Power Series Method (RPSM)(Aksaray Üniversitesi, 2021) Kaya, AhmetBu çalışmada, Drinfeld–Sokolov–Satsuma–Hirota (DSSH) denkleminin yaklaşık çözümü rezidual kuvvet seri metodu (RKSM) kullanılarak elde edildi. Kesirli türevleri karakterize etmek için uyumlu türev yaklaşımı kullanıldı ve farklı operatör değerleri için RKSM yaklaşık çözümleri kesin çözümlerle çeşitli tablo ve grafikler kullanılarak karşılaştırıldı. Sonuçlar; uygulanan tekniğin kullanımının kolay, çok başarılı ve tutarlı olduğunu göstermekle birlikte daha önceki yapılmış çalışmalara kıyasla da önemli bir ilerleme getirdiğini göstermektedir.Öğe Bir köşe akışı etrafındaki zorlanmış taşınımla ısı transferine ısıl ışınımın etkisi(DergiPark, 2009) Kaya, Ahmet; Aydın, OrhanBu çalışmada, bir köşe akışı etrafında zorlanmış taşınımla ısı transferine ısıl ışınımın etkisi incelenmiştir. Problemi tanımlayan lineer olmayan kısmi diferansiyel denklemler, benzerlik yöntemiyle sınır tabaka denklemlerine dönüştürülmüş ve Keller-box yöntemiyle çözülmüştür. Boyutsuz basınç m, emme/üfleme fw, ışınım Rd ve yüzey sıcaklık oranı ?w parametrelerinin hız ve sıcaklık profilleri ve ısı transferi üzerindeki etkileri belirlenmiştir. Bazı özel limit durumlar için elde edilen sonuçlar, literatürde verilen sonuçlarla karşılaştırılmış ve mükemmel bir uyum elde edilmiştir.Öğe Comparison of experimental data with results of some drying models for regularly shaped products(Springer, 2010) Kaya, Ahmet; Aydın, Orhan; Dinçer, İbrahimThis paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during drying at various temperatures (e.g., 30, 40, 50 and 60A degrees C) at specific constant velocity (U = 1 m/s) and the relative humidity phi = 30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient), and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases considered. The effective diffusivity values were evaluated between 0.741 x 10(-5) and 5.981 x 10(-5) m(2)/h for slab products, 0.818 x 10(-5) and 6.287 x 10(-5) m(2)/h for cylindrical products and 1.213 x 10(-7) and 7.589 x 10(-7) m(2)/h spherical products using the Model-I and 0.316 x 10(-5)-5.072 x 10(-5) m(2)/h for slab products, 0.580 x 10(-5)-9.587 x 10(-5) m(2)/h for cylindrical products and 1.408 x 10(-7)-13.913 x 10(-7) m(2)/h spherical products using the Model-II.Öğe Drying kinetics and sorption isotherms of cornelian cherry fruits(Desalination Publications, 2010) Kaya, Ahmet; Aydın, OrhanIn this study, drying kinetics and sorption isotherms of cornelian cherry fruit are investigated under various drying air conditions. Experiments are conducted in a lab-scale convective drier under the following drying conditions: temperatures at 25, 30, 40, 50 and 60 degrees C; velocities at 0.3, 0.6 and 0.9 m/s; relative humidity values at 25%, 40%, 55% and 70%. Sorption isotherms of the dried cornelian cherry fruit are determined for different temperatures and water activity values at first. At a given water activity, the results show that the equilibrium moisture content decreases with increase in temperature. The experimental sorption curves are then described by the GAB, Oswin, Smith and Halsey models. A nonlinear regression analysis method was used to evaluate the constants of the sorption equations. The GAB model was found to be suitable for describing the sorption curves. Later, drying experiments are conducted for various values for drying air. The experimental moisture data were fitted to some models available in the literature, mainly the Henderson and Pabis model, the Lewis model and the two-term exponential model and, a good agreement was observed.Öğe Dryıng kınetıcs and moısture transfer parameters of hazelnut(Wıley-Blackwell, 2011) Kaya, Ahmet; Aydın, Orhan; Akgün, MithatIn this experimental study, drying kinetics, sorption isotherms and mass transfer parameters (mainly the diffusion coefficient and hm) of hazelnut are investigated under various drying air conditions. Experiments were conducted in a lab-scale convective drier under the following drying conditions: temperatures at 25C, 35C, 45C and 55C; velocities at 0.3, 0.6 and 0.9 m/s; relative humidity values at 20%, 40%, 60% and 80%. Initially, sorption isotherms of the dried hazelnut are determined for different temperatures and equilibrium relative humidity values. Then, the drying characteristics of hazelnut are determined for various values of drying air parameters tested. In addition, the mass transfer parameters (i.e., Bi, moisture diffusion coefficient and hm) of hazelnut were evaluated using a correlation. The Bi numbers were in the range 0.42161.4806 and moisture diffusion coefficient and hms in the range from 0.7056 x 10(-9) to 3.2933 x 10(-9) and from 1.2401 x 10(-7) to 1.7361 x 10(-7) m/s, respectively.Öğe Effects of buoyancy and conjugate heat transfer on non-Darcy mixed convection about a vertical slender hollow cylinder embedded in a porous medium with high porosity(Pergamon-Elsevier Science Ltd, 2011) Kaya, AhmetThis study investigates mixed convection heat transfer about a vertical slender hollow cylinder in the buoyancy and conjugate heat transfer effects in the porous medium with high porosity. The non-similar solutions using the Keller box method are obtained. The wall conduction parameter p, the porous medium parameter k(1) the Forchheimer parameter F* and the Richardson number are the main parameters. For various values of these parameters the local skin friction and local heat transfer parameters are determined. The validity of the methodology is checked by comparing the results with those available in the open literature and a fairly good agreement is observed. Finally, it is determined that the local skin friction and the local heat transfer coefficients increase with an increase buoyancy parameter Ri, porous medium parameter k(1), Forchheimer parameter F* and decrease with conjugate heat transfer parameter p. (C) 2010 Elsevier Ltd. All rights reserved.Öğe Effects of MHD and thermal radiation on forced convection flow about a permeable horizontal plate embedded in a porous medium(Türk Isı Bilimi ve Tekniği Derneği, 2012) Kaya, Ahmet; Aydın, OrhanIn this study, forced convection heat transfer about a permeable horizontal plate in the presence of magnetic field and thermal radiation effects in the porous medium are investigated. The fluid is assumed to be incompressible and dense. The nonlinear parabolic partial differential equations governing the flow are transformed into the non-similar boundary layer equations. The Keller box method is used to solve these equations. The governing dimensionless parameters arising from dimensionless governing equations are as follows: the porosity ?, the inertia parameter ?, the magnetic parameter Mn, the radiation–conduction parameter Rd, the surface temperature parameter ?w, and the suction/injection parameter fw. The effects of these parameters on the local skin friction and local heat transfer parameters as well as the velocity and temperature profiles are analyzed. The validity of the solution methodology and the results are questioned by comparing the findings obtained with those available in the literature and, a fairly good agreement is reached.Öğe Effects of mild and thermal radiation on forced convection flow about a permeable horizontal plate embedded in a porous medium(Turkish Society of Thermal Sciences and Technology, 2012) Kaya, Ahmet; Aydın, OrhanIn this study, forced convection heat transfer about a permeable horizontal plate in the presence of magnetic field and thermal radiation effects in the porous medium are investigated. The fluid is assumed to be incompressible and dense. The nonlinear parabolic partial differential equations governing the flow are transformed into the non-similar boundary layer equations. The Keller box method is used to solve these equations. The governing dimensionless parameters arising from dimensionless governing equations are as follows: the porosity epsilon, the inertia parameter gamma, the magnetic parameter Mn, the radiation conduction parameter R-d, the surface temperature parameter theta(w), and the suction/injection parameter f(w). The effects of these parameters on the local skin friction and local heat transfer parameters as well as the velocity and temperature profiles are analyzed. The validity of the solution methodology and the results are questioned by comparing the findings obtained with those available in the literature and, a fairly good agreement is reached.Öğe Effects of thermal radiation on steady mhd mixed convective heat transfer flow over an impermeable inclined plate embedded in a porous medium(2011) Aydın, Orhan; Kaya, AhmetThis study investigates mixed convection heat transfer about an impermeable inclined plate in the presence of magnetoand thermal radiation effects in a porous medium. The fluid is assumed to be incompressible and dense. The nonlinear coupled parabolic partial differential equations governing the flow are transformed into the non-similar boundary layer equations, which are then solved numerically using the Keller box method. The effects of porosity e, mixed convection parameter Ri, angle of inclination ?, magnetic parameter M, and radiation-conduction parameter Rd on the velocity and temperature profiles as well as on the local skin friction and local heat transfer are presented and analyzed. The validity of the methodology and analysis is checked by comparing the results obtained for some specific cases with those available in the literature. © 2011 by Begell House, Inc.Öğe Heat and mass transfer from a horizontal slender cylinder with a magnetic field effect(Türk Isı Bilimleri ve Tekniği Derneği, 2011) Kaya, AhmetThe problem of steady laminar magnetohydrodynamic (MHD) forced convective heat and mass transfer about a horizontal slender cylinder is studied numerically. A uniform magnetic field is applied perpendicular to the cylinder. The nonlinear partial differential equations governing the flow are transformed into the similar boundary layer equations, which are then solved numerically using the Keller box method. The transverse curvature parameter, the magnetic parameter, the Prandtl number and the Schmidt number are the main parameters. For various values of these parameters, the local skin friction, heat transfer and mass transfer parameters are obtained. The validity of the methodology is checked by comparing the results with those available in the open literature and a fairly good agreement is observed. Finally, it is determined that the local skin friction coefficient, the local heat transfer coefficient and the local mass transfer coefficient increase with an increase the magnetic parameter Mn and transverse curvature parameter.Öğe MHD mixed convective heat transfer flow about an inclined plate(SPRINGER, 2009) Aydın, Orhan; Kaya, AhmetMixed convection heat transfer about a semi-infinite inclined plate in the presence of magneto and thermal radiation effects is studied. The fluid is assumed to be incompressible and dense. The nonlinear coupled parabolic partial differential equations governing the flow are transformed into the non-similar boundary layer equations, which are then solved numerically using the Keller box method. The effects of the mixed convection parameter R (i), the angle of inclination alpha, the magnetic parameter M and the radiation-conduction parameter R (d) on the velocity and temperature profiles as well as on the local skin friction and local heat transfer parameters. For some specific values of the governing parameters, the results are compared with those available in the literature and a fairly good agreement is obtained.Öğe MHD-mixed convection from a vertical slender cylinder(ELSEVIER SCIENCE BV, 2011) Aydın, Orhan; Kaya, AhmetThe problem of steady laminar magnetohydrodynamic (MHD) mixed convection heat transfer about a vertical slender cylinder is studied numerically A uniform magnetic field is applied perpendicular to the cylinder The resulting governing equations are transformed into the non-similar boundary layer equations and solved using the Keller box method The velocity and temperature profiles as well as the local skin friction and the local heat transfer parameters are determined for different values of the governing parameters mainly the transverse curvature parameter the magnetic parameter the electric field parameter and the Richardson number For some specific values of the governing parameters the results agree very well with those available in the literature Generally it is determined that the local skin friction coefficient and the local heat transfer coefficient increase increasing the Richardson number R(1) (i e the mixed convection parameter) electric field parameter E(1) and magnetic parameter MnÖğe Quantum mechanics approach for appropriately chosen hamiltonian(Aksaray Üniversitesi, 2022) Kaya, AhmetRisk theory has always played a significant role in mathematical finance and actuarial sciences. A novel approach to the risk theory of non-life insurance is quantum mechanics. To compute finite-time non-ruin probability, I introduce the quantum mechanics formalism in discrete space and continuous space with the appropriately chosen Hamiltonian. By using the quantum mechanics approach and the stochastic method, the non-ruin operator is defined, and tensor products of operator concepts are presented for several examples. In this paper, Dirac notations are operated to find the Hamiltonian matrix with the eigenvector basis for two and three-state cases, and its tensor product version with a change of basis.Öğe The effect of conjugate heat transfer on MHD mixed convection about a vertical slender hollow cylinder(Elsevıer Scıence Bv, 2011) Kaya, AhmetThe problem of steady laminar magnetohydrodynamic (MHD) mixed convection heat transfer about a vertical slender hollow cylinder is studied numerically under the effect of wall conduction A uniform magnetic field is applied perpendicular to the cylinder The non similar solutions using the Keller box method are obtained The wall conduction parameter the magnetic parameter and the Richardson number are the main parameters For various values of these parameters the local skin friction and local heat transfer parameters are determined The validity of the methodology is checked by comparing the results with those available in the open literature and a fairly good agreement is observed Finally it is determined that the local skin friction and the local heat transfer coefficients increase with an increase the magnetic parameter Mn and buoyancy parameter Ri and decrease with conjugate heat transfer parameter p (C) 2010 Elsevier B V All rights reservedÖğe The effect of radiation on forced convection flow around a wedge(Turkish Soc Thermal Sciences Technology, 2009) Kaya, Ahmet; Aydın, OrhanIn this study, effect of thermal radiation oil forced convection heat transfer about a permeable isothermal wedge is investigated. The nonlinear partial differential equations governing the flow are trails formed into the similar boundary, layer equations, which are then solved numerically using the Keller box method. The effects of the dimensionless pressure parameter m, the scution/injection parameter f(w), the radiation-conduction parameter R(d) and the surface temperature parameter 0(w) on the velocity and temperature profiles as well as oil heat transfer parameters are presented and analyzed. The results are compared with those available in the existing literature and all excellent agreement is obtained.
