Necdet ÖZBALTA, Ali GÜNGÖR, Gökhan GÜRLEK

Solar tunnel drying characteristics and mathematical modelling of tomato

Domates kurutma denemeleri İzmir, Türkiye’de gerçekleştirilmiştir. Bu amaçla yeni geliştirilen tünel tipi güneşli kurutucu tasarlanmış ve imal edilmiştir. İmal edilen güneşli kurutucu, havalı toplayıcı, kurutma odası ve hava sirkülasyon sisteminden oluşmaktadır. Havalı toplayıcıdan elde edilen ısıtılmış hava, fan aracılığıyla domateslerin üzerinden geçirilmiştir. Kurutma denemelerinde Rio Grande tip domates kullanılmıştır. Kurutma periyodu süresince, kurutma hava sıcaklığı, bağıl nem, hava debisi, güneş ışınım değeri ve kurutucunun farklı noktalarından alınan numunelerdeki kütle kayıpları düzenli olarak takip edilmiştir. Kurutma zamanının kütle kaybıyla ilişkisi bağıntılarla takip edilmiştir. Kurutma eğrileri dikkate alınarak oniki farklı matematiksel model karşılaştırılmıştır. Istatistiksel analiz sonuçlarına göre deneysel kurutma verilerine en iyi uyum sağlayanın R2 değerinin 0.9967 olduğu two-term matematiksel model olduğu görülmüştür.

Domatesin tünel tipi güneşli kurutucudaki kurutma karakteristikleri ve matematiksel modellemesi

Solar drying experiments of tomato were conducted in Izmir, Turkey. In this purpose, new type tunnel solar dryer was designed and manufactured. Solar dryer consist of an air collector, drying chamber and an air circulation system. Heated air in solar air collector was forced through the tomatoes by a blower. Rio Grande type tomato was used for drying experiments. During the drying period, drying air temperature, relative humudity, air flow rates, solar radiation, and lose of mass were measured continuously in different part of the dryer. Drying time was examined with mass ratio as exponantial and polynomial correlations. Twelve different mathematical models available in literature were compared using their coefficient of determination of estimate solar drying curves. According to statistical analysis results, the two-term drying model has shown a better fit to the experimental drying data of tomato with a coefficient of determination R2 of 0.9967 as compared to other models.

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