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Öğe Numerical and experimental investigation of solar chimney power plant system performance(Taylor & Francis, 2020-03-15) Karakaya, Hakan; Durmuş, Aydın; Avcı, Ali SerkanA prototype of a solar chimney power plant was performed by modeling in this study. The performed prototype was experimentally confirmed. Temperature, velocity, and radiation values were measured to actualize the confirmation. Experimental data that were obtained to determine the performance of solar chimney whose prototype was actualized by the help of measured values were computationally analyzed. The geometry of a solar chimney in the analysis was bidimensionally (2D) drawn on an axis of symmetry. The numerical simulation was analyzed with computational fluid dynamics (CFD) method. Since analysis results show that there is turbulent flow in system (RNG), k-ɛ turbulence model was used. Continuity, momentum, and energy equations were applied to the solar chimney system via the finite volume method. Moreover, DO (discrete ordinates) model was inserted in analysis to evaluate the radiation effect in the collector area. In addition to all these, correlation results between SPSS 17 statistics program and data obtained were evaluated. Finally, with reference to the comparison between numerical and experimental results, data obtained and numerical data are close to each other; the prototype is applicable to the real systems.Öğe Analysis of sunshine hours and global solar radiation for Mardin of Turkey(ISITES, 2015) Karakaya, Hakan; Kallioğlu, Mehmet Ali; Avcı, Ali SerkanHaving a strategic area, the energy industry has a critical importance in development policy of a country. Demands of renewable energy have increased in recent years due to energy price, global warming and climatic change. Therefore, the concerns about solar energy, one of the most important clean energy sources, have risen in the last decades. In this study, the empirical solar correlations developed in Turkey and some other countries were investigated for the province of Mardin, Turkey. The compatibility of solar radiation models inspected in terms of statistics was tested by determining the nearest model according to measured data. In addition to climate data which is specific to this region, prediction of Angstroms model was developed to estimate global solar radiation in Mardin. These models, since the mathematical models with the highest compatibility represent the measured data statistically well, it is understood that it can easily be used for daily global solar radiation on horizontal surfaces. The data of the model were obtained from Solar Energy Potential Atlas (GEPA) of Electrical Power Resources Survey Administration (EIE). Angstrom-type model parameters were developed to forecast sunshine average and to compute empirical coefficients for Mardin. Monthly predicted global solar radiation mean values were compared with observed values using statistical parameter coefficient of regression analysis (R²), mean bias error (MBE), root mean square error (RMSE), mean percentage error (MPE), mean absolute percentage error (MAPE), t-statistic (tsat) and the percent error (e) method developed in order to test the compliance of the models. The best developing ideal model was found to be quadric H/H0=-1,3049 (S/S0 ) 2 +2,2791(S/S0)-0,4143 and R 2 0,9492 determined in terms of utilizing the solar radiation potential in Mardin, Turkey