Tuncay GÜNHAN, Vedat DEMİR, Abdülkadir YAĞCIOĞLU

Mathematical modelling of convection drying characteristics of artichoke (Cynara scolymus L.) leaves

Bu çalışmada enginar yapraklarının (Cynara scolymus L. ) konveksiyonel kuruma karakteristiklerinin matematikselmodellenmesi sunulmuştur. Denemelerde kullanılan enginar yaprakları Ege Üniversitesi yerleşke alanı içerisindekiZiraat Fakültesi deneme parsellerinden toplanmıştır. Doğranmış enginar yaprakları, laboratuvarda çeşitli sıcaklıklarda(40, 50, 60 ve 70 °C) ve hava hızlarında (0.6, 0.9 ve 1.2 m s -1) sabit bağıl nem değerinde (% 15±2) kurutma denemelerinde kullanılmıştır. Enginar yapraklarının 40, 50, 60 ve 70 °C sıcaklıklarda % 10 nem içeriğine (yb) ulaşmaları 0.6 m s-1 sabithava hızında sırasıyla yaklaşık olarak 4.08, 2.29, 1.32 ve 0.98 h sürerken, 0.9 m s-1 sabit hava hızında yaklaşık olarak3.83, 1.60, 0.96 ve 0.75 h sürmüştür. 40, 50, 60 ve 70 °C sıcaklıklarda kurutma havası hızını 1.2 m s-1ye kadar artırmakkuruma süresini sırasıyla 3.5, 1.54, 1.04 ve 0.71 he kadar düşürmüştür. Literatürde yer alan çeşitli kuruma modelleri,belirtme katsayısı (R2), ortalama hata kareleri karekökü (RMSE), khi-kare ( χ2) ve mutlak bağıl hata (P) değerlerikullanılarak karşılaştırılmıştır. Yapılan çalışma sonunda denemelerin yapıldığı koşullar altında enginar yapraklarınınkurumasını en iyi Midilli vd. kuruma modelinin açıkladığı belirlenmiştir.

Enginar yapraklarının (Cynara scolymus L.) konveksiyonel kuruma karakteristiklerinin matematiksel modellenmesi

This paper presents the results of a study on mathematical modelling of convection drying of artichoke (Cynara scolymusL.) leaves. Artichoke leaves used for drying experiments were picked from the agricultural faculty experimentation feldson the campus area of Ege University. Chopped artichoke leaves were then used in the drying experiments performedin the laboratory at different air temperatures (40, 50, 60 and 70 °C) and airfow velocities (0.6, 0.9 and 1.2 m s -1)at constant relative humidity of 15±2%. Drying of artichoke leaves down to 10% wet based moisture content at airtemperatures of 40, 50, 60 and 70 °C lasted about 4.08, 2.29, 1.32 and 0.98 h respectively at a constant drying air velocityof 0.6 m s -1 while drying at an air velocity of 0.9 ms -1 took about 3.83, 1.60, 0.96 and 0.75 h. Increasing the drying airvelocity up to 1.2 m s-1 at air temperatures of 40, 50, 60 and 70 °C reduced the drying time down to 3.5, 1.54, 1.04 and0.71 h respectively. Different mathematical drying models published in the literature were used to compare based on thecoeffcient of multiple determination (R2), root mean square error (RMSE), reduced chi-square ( χ2) and relative deviationmodulus (P). From the study conducted, it was concluded that the Midilli et al drying model could satisfactorily explainconvection drying of artichoke (Cynara scolymus L. ) leaves under the conditions studied.

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