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WOS: 000324787600060, An original model for thermodynamic analysis of a batch type fluidized bed dryer is proposed herein considering two separate systems comprised of drying air medium as a control volume and particles to be dried as a control mass. By means of the proposed model, energetic and exergetic analyses of a drying column of a batch type fluidized bed dryer are carried out as an original contribution to literature since there is no such like model in which the analyses are performed considering two separate systems. The energetic efficiencies evaluated by means of the proposed model using the data in literature are compared with those in literature and a good conformity is satisfied with an acceptable error margin of +/- 9%. A new correlation is also developed with a mean deviation of 10% in order to evaluate the energetic efficiency for not only corn drying process but also drying processes of other particles at inlet air temperature of 50 degrees C. Effects of air mass flow rate, mass of particle and ambient temperature on energetic and exergetic efficiencies are analyzed and some concluding remarks are highlighted for further studies.

Theoretical and experimental study of the paper drying process are presented. A mathematical model developed for combined heat ad mass transfer analysis of paper drying is given for both impinging air jets and through air drying methods. In this model, it is simply assumed that during the drying period of the paper has porous media and on the drying surface the vapour pressure of the evaporating liquid remains at a quasi-saturated value corresponding to the temperature of the liquid. The calculated transient paper temperatures in both methods agree well with the experimental results.

In this study, plum slices were dried in three different driers (tray, fluid bed, and heat pump (HP) driers). Drying experiments were carried out at an air temperature range of 45-55 °C with an air velocity of 1.5 m/s. The performance of the driers along with their main components was evaluated and compared by using the exergy analysis method. The most important component for improving the system efficiency was determined to be the fan-heater combination for both the tray and fluid bed driers, and the motor-compressor assembly for the HP drier. The exergy loss and flow diagram (the so-called Grassmann diagram) of the driers was also presented to give quantitative information regarding the proportion of the exergy input dissipated in the various system components. Effects of the drying air temperature on the performance of the drying process were discussed. The highest exergetic efficiency values were obtained to range from 72.72 to 75.66 per cent for the HP drier, followed by the tray and fluid bed driers varying between 37.94 and 39.46 per cent, and between 22.83 and 24.07 per cent, respectively., TÜBİTAK project no. 106M482

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2010, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2010, Bu çalışmada, bir tekstil ürünün içerdiği nemin uzaklaştırılması sırasında kullanılan havanın debisinin, sıcaklığının ve özgül neminin, kumaş cinsine bağlı olarak; kurutma verimi üzerine yaptığı etkinin derecesi araştırılmıştır. Kumaş cinsi olarak, iki farklı dokuma yapısına ait, % 100 pamuklu kumaş türü kullanılmıştır. Kurutma işlemi sabit kurutma fazı bitinceye kadar sürülmüştür. Deneyler, buhar sıkıştırmalı soğutma çevrimi ile çalışan evsel bir tekstil kurutma makinesinde yapılmıştır. Çalışma sonucunda, 2 kumaş türü ve 2 özgül nem değeri için ayrı olarak korelasyon denklemleri oluşturulmuştur. Korelasyon denklemine göre, tekstil kurutma verimi sıcaklıkla lineer olarak değişirken, hava debisi ile parabolik olarak değiştiği görülmüştür. Dokuma yapısının, kurutma verimine etkisi yüksek debilerde görülmüştür., In this thesis; effect of flow rate, temperature, specific humidity of process air, which uses to remove moisture from wetted textile fabric, as depending on type of textile fabric is investigated. Two different constructed woven fabric made from % 100 cotton are used as sample. Drying process is carried on until constant drying period is completed in experiments. Experiments are carried on domestic textile dryer machine works by principle of vapor compression refrigeration cycle. In conclusion, correlations are formed depend on two different types fabric sample and two spesific humidity. According to correlation equations, textile drying efficiency is linear with temperature change, while it varies as a parabolic by air flow rate change. Effects of woven construction on drying efficiency increases by air flow rate., Yüksek Lisans, M.Sc.