Energy and exergy analyses of coconut drying in a solar tunnel drier

This paper presents energy and exergy analyses of solar drying of coconuts in a hemispherical solar tunnel drier. Coconuts were dried from an initial moisture content of about 55% (w.b.) to 7% (w.b.) in the solar tunnel drier in 60 hrs whereas the open sun drying process takes 153 hrs for reducing the moisture content to the same level. The drying experiments were conducted at a mass flow rate of 7.25 kg/s with an average air velocity of 0.1 m/s. Using the first law of thermodynamics, energy analysis was carried out to estimate the amount of energy received by the solar tunnel drier and the ratios of energy utilization. However, exergy analysis was accomplished to determine the exergy loss and exergy efficiency by applying the second law of thermodynamics. Energy utilization, energy utilization ratio, exergy inflow and exergy loss in the drier were studied and these values are found to be increased with increasing solar radiation. The exergy inflow and exergy loss in the drier varied between 0.194 kJ/s–8.18 kJ/s and 0.085 kJ/s–5.377 kJ/s respectively. The exergy efficiency of the drier varied between 23.6%–53%.

Comparison of quality of anardana (dried arils) prepared in mechanical cabinet and solar tunnel drier from wild pomegranate (Punica granatum L.) fruits procured from different locations of Himachal Pradesh, India

The dried arils (anardana) prepared from wild pomegranate fruits (Punica granatum L.) are widely used as an acidulant in culinary purposes and in formulations of various ayurvedic medicines which are helpful in curing a number of ailments. As there is a wide variation among the quality of fruits which is due to geographic conditions, climatic factors and genetic variability so anardana was prepared from the fruits of different locations under different drying modes. The prepared product was further compared for its physico-chemical, antioxidant and sensory characteristics. Anardana prepared under mechanical cabinet drier and solar tunnel drier was comparable in terms of its various quality characteristics. While comparing the locations for the procurement of raw material, best quality anardana in terms of various quality attributes like colour, TSS [(total soluble solids) (40.35 oB)], total sugars (26.15 %), anthocyanins (37.97 mg/100 g), total phenols (176.46 mg GAE/100 g), flavonoids (39.45 mg QuE/100 g), antioxidant activity (59.53 %), starch (2.87 %) and sensory characteristics was prepared from the fruits of Karsog location (1265 meters above mean sea level) of Himachal Pradesh, India.

A Research on Solar Greenhouse Dryer

For taking away the humidity material drying procedure is achieved. Evolution of roof variety, particularly, solar cycle drier kayak drier solar tunnel drier, and greenhouse sprays length research workers have learned greenhouse drier. Inside this newspaper drier below convection variety and convection sort have been all studied. Greenhouse drier provides rather large excellent product compared to sun drying that is open plus the harvest declines are reduced by it. It's been discovered that the use of rainwater drier below convection lessens moisture material in addition to drying speed is rapid and comparative humidity is significantly less than convection manner.

Performance Evaluation of Solar Tunnel Dryer for Drying of Garlic.

This paper presents dying efficiency and performance of the solar tunnel dryer for drying of garlic. The dryer is a tunnel like semi-cylindrical in shape, poly house made up of UV-stabilized polyethylene sheet. The capacity is large enough that it can be used to dry 400 kg of garlic under controlled environmental conditions. The temperature inside the dryer was always higher than the ambient and the variation varied from 8-30 ºC. Initial moisture content of garlic was reduced from 66 % (w.b.) to about 9 % (w.b.) in 9 days which is considered to be a safe level. During the drying process the average thermal efficiency of the drier was estimated to be about 13.45 %. Drying time was considerably reduced with the use of a solar tunnel drier and pressing of the sample. Also, the final dried garlic was found to be good in terms of quality and sensory evaluation shows that it is highly acceptable.