GÜNEŞ HAVUZLARINDA ISI ÇEKME ORANININ BELİRLENMESİ

Abstract

Bu çalışmada, bir güneş havuzunda ısı çekme oranı, doğrudan çözücü PARDISO ile Ayrık Ordinatlar Yöntemi kullanılarak iç içe parçalara ayrılıp çok iş parçacıklı ön düzenleme algoritması ile sayısal olarak araştırılmış ve sayısal yaklaşımların simülasyon doğruluğu için eşanjörsüz güneş havuzunda yapılan ön nümerik sonuçlar deneysel verilerle Akdeniz iklim koşullarında karşılaştırılmıştır. Daha sonra, güneş havuzu önceki bir deney sistemi ile aynı boyutta modellenmiş ve ısı depolama bölgesine bir ısı eşanjörü yerleştirilmiş ve COMSOL ticari yazılımı ile sıcak suyun belirli bir akışta dışarı alınması için simülasyon gerçekleştirilmiştir. Adana için güneş konumu tanımlanmış ve ASHRAE Weather Data Viewer 5.0 ile işlenerek ortam verileri elde edilmiştir. Sonuç olarak, 0.007 kg/s debi için maksimum ve minimum ısı çekme oranı Temmuz ayında % 13.39 ve Eylül ayında % 2.96 olarak hesaplanmıştır; 0.014 kg/s debi için sırasıyla Haziran'da %24.27 ve Eylül'de %3.23'tür.

Keywords

• Güneş enerjisi
• güneş havuzu
• ısıl enerji
• ısı transferi
• ısı eşanjörü

THE DETERMINATION OF THE HEAT EXTRACTION RATIO IN THE SOLAR POND

Abstract

In this study heat extraction ratio of a solar pond was investigated numerically by using the Discrete Ordinates Method (DOM) with the direct solver PARDISO by using nested dissection multithreaded preordering algorithm, and the findings without exchanger were compared with experimental data to validate simulation accuracy of numerical approaches in the Mediterranean climatic condition. The solar pond was modeled with the same dimension as a previous experimental system and a heat exchanger was placed in the heat storage zone and simulation to take out the hot water at a certain flow was performed with the commercial software COMSOL. The solar position was defined for Adana and ambient data was obtained by processing the ASHRAE Weather Data Viewer 5.0. As a result, the maximum and minimum heat extraction ratio (HER) is calculated as 13.39 % in July and 2.96 % in September for a flow rate of 0.007 kg/s; 24.27 % in June, and 3.23 % in September for a flow rate of 0.014 kg/s, respectively.

Keywords

• Solar energy
• solar pond
• thermal energy
• heat transfer
• heat exchanger

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