Experimental Investigation and Theoretical Modelling of Solar Dryer Using Evacuated Tube Collector

2015 ◽  
Vol 787 ◽  
pp. 147-151 ◽  
Author(s):  
R. Manivel ◽  
S. Sivakumar ◽  
T. Rajagopal
Keyword(s):  
Theoretical Modelling ◽  
Drying Time ◽  
Evacuated Tube Collector ◽  
Solar Dryer ◽  
Coimbatore District ◽  
Temperature Ranges ◽  
Drying Models ◽  
Evacuated Tube ◽  
Drying Chamber

An indirect type solar dryer is fabricated with the components like evacuated tube collector, drying chamber and blower. The performance of the drier is evaluated by carrying out drying experiments with copra at Coimbatore district Tamilnadu, India. A short survey of these showed that applying the indirect type solar dryer not only significantly reduced the drying time but also resulted in many improvements in the quality of the dried products. The temperature of the drying chamber ranges from 55°C to 75°C while the ambient temperature ranges from 28°C to 38°C. Nine basic solar drying models were used to fit the experimental data of copra. For experimental results, the logarithmic model showed the best curve fitting with highest correlation coefficient (R2) and lowest value of RMSE (Root Mean Square Error). Solar dried copra obtained is free from smoke, dust, bird and rodent damage.

Solar Assisted Dehydrator for Decentralized Controlled and Homogeneous Multi-Product Drying

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Waseem Amjad ◽  
Muhammad Waseem ◽  
Anjum Munir ◽  
Abdul Ghafoor ◽  
Furqan Asghar ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Air Distribution ◽  
Drying Time ◽  
Specific Product ◽  
Heating Source ◽  
Batch Type ◽  
Evacuated Tube Collector ◽  
Drying Rates ◽  
Evacuated Tube ◽  
Drying Chamber

Abstract Batch type food dryers are common for drying agricultural produce due to simple in design, but they are prone to nonuniform drying and significant heat cost exclusively if they fall in the medium to large size range. The current study illustrates a solar hybrid food dryer using a gas burner and solar collector (evacuated tube collector, ETC) as heating source along with an inline perforation inside the drying chamber to obtain spatial drying homogeneity. Air distribution was assessed through three-dimensional simulation using computational fluid dynamics (CFD) analysis. Performance trials were conducted under three heating options (ETC, gas, and dual) using green chilies at 60 °C. Throughout drying chamber, under all heating modes, the average difference in drying rates ranged from 0.61 to 1.30 kg water/kg dry matter, demonstrating homogeneous drying. Simulated and experimental results of air distribution were found to be in agreement with each other. Using three options for thermal heating (ETC, gas, and dual) and an overall 58% efficiency for evacuated tube collector, the specific energy for moisture evaporation was found to be 4.5–5.7 MJ/kg and specific product energy 19.2–24.9 MJ/kg. In case of dual heating option, the energy supplied by solar and gas sources for a 20 hours period was 50.64% (160.22 MJ) and 49.35% (156.13 MJ), respectively. Compared with dual heating option, energy cost can be reduced by 68% if only solar energy is used as a heating option but with a protracted drying time.

scholarly journals An Experimental Study and Analysis on Solar Drying of Bitter Gourd Using an Evacuated Tube Air Collector in Thanjavur, Tamil Nadu, India

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
AR. Umayal Sundari ◽  
P. Neelamegam ◽  
C. V. Subramanian
Keyword(s):  
Moisture Content ◽  
Tamil Nadu ◽  
Research Work ◽  
Bitter Gourd ◽  
Sun Drying ◽  
Solar Dryer ◽  
Drying Rates ◽  
Evacuated Tube ◽  
Drying Chamber

The objective of this research work is to design and develop a forced convection solar dryer using evacuated tube air collector and study its performance on bitter gourd in Thanjavur District, Tamilnadu, India. The designed solar dryer consists of a drying chamber, evacuated tube air collector, a blower, and a chimney. Drying parameters, moisture ratio and drying rates, are calculated and their performance is compared with natural sun drying. The results of the present study show that the proposed solar dryer has greater efficiency, and the moisture content of bitter gourd is reduced from 91% to 6.25% in 6 hours as compared to 10 hours in natural sun drying. In this solar dryer, the products are uniformly dried, and the moisture content of the sample is controlled. It is found that the quality of the dried bitter gourd using solar dryer is higher than the natural sun-dried bitter gourd.

Experimental Investigation of Active Solar Dryer for Drying of Chili

2014 ◽  
Vol 953-954 ◽  
pp. 16-19 ◽  
Author(s):  
Yuttachai Keawsuntia
Keyword(s):  
Experimental Investigation ◽  
Solar Collector ◽  
Agricultural Product ◽  
Drying Time ◽  
Sun Drying ◽  
Hot Air ◽  
Solar Dryer ◽  
Drying Chamber ◽  
Better Than

This research paper presents the experimental results of drying of chili by using the active solar dryer and sun drying because of chili is a commercial agricultural product of Thailand. The active solar dryer consisted of a solar collector, a drying chamber and a chimney. The small fans were installed in the solar collector of active solar dryer to provide the air flow circulated in the solar collector and a drying chamber. Drying of chili of 20 kg from moisture content 84 percent wet basis to 10 percent wet basis following the Thai Agricultural Standard (TAS 3001-2010) showed that the use of the active solar dryer to make the drying time reduced about 28.7 percent compared with sun drying because of the hot air temperature inside the drying chamber higher than the ambient temperature about 10 to 15 . The quality of dried chili from the active solar dryer better than dried chili from sun drying.

scholarly journals Solar Drying System Integrated with Phase Change Material (PCM)

2020 ◽  
Vol 9 (3) ◽  
pp. 1897-1902
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Agricultural Products ◽  
Paraffin Wax ◽  
Cfd Simulations ◽  
Solar Dryer ◽  
Flat Plate Collector ◽  
Change Material ◽  
Drying Chamber

The post-harvest losses for agricultural products are around 30%-40% [1]. Drying is a one of the necessary processes for the preservation of agricultural products. Agricultural products require hot air of temperature above 40 ºC for drying. Open sun drying takes more time for drying of products due to slower drying rates. Also, various factors hamper the quality of the dried product. Due to the moisture content in the products bacterial attack is possible. India being the tropical region has good solar radiation. It is advisable to use the solar dryer to avoid spoilage of quality of products [2]. In this work, the compact and portable forced convection solar dryer designed and developed for drying chilies with thermal energy storage. Solar dryer is having capacity of 15 kg and it consists of the flat plate collector based air heating system with thermal energy storage. Paraffin wax used as phase change material (PCM). The CFD simulations carried out for the solar dryer to study the temperature distribution over the surfaces of the flat plate collector and inside the drying chamber, velocity of air and phase change behavior of paraffin wax inside the trays. The energy stored in the paraffin wax and time required for charging and discharging of paraffin wax is found out. The time for which temperature in the drying chamber is maintained above 40 oC is also found out. Results of CFD simulations validated with the experimental results.

scholarly journals Drying of cherry tree chips in the experimental biomass dryer with solar collector

2012 ◽  
Vol 58 (No. 1) ◽  
pp. 16-23 ◽  
Author(s):  
T. Ivanova ◽  
B. Havrland ◽  
P. Hutla ◽  
A. Muntean
Keyword(s):  
Solar Collector ◽  
Biomass Conversion ◽  
Monitoring And Evaluation ◽  
Drying Process ◽  
Cherry Tree ◽  
Drying Time ◽  
Solid Biofuels ◽  
Relative Air Humidity ◽  
Drying Chamber

Drying significantly influences the process of a biomass conversion into the renewable energy source as well as quality of solid biofuels (briquettes, pellets). The research is focused on monitoring and evaluation of the drying process in the case of cherry tree chips drying in experimental biomass dryer with solar collector. The dryer has been conceived as a result of the project which was realized at the State Agrarian University of Moldova. Technological and construction specifics of the biomass dryer are described in the paper. The moisture content of the cherry tree chips was observed in dependence of the drying time and at different locations of the drying chamber. The drying process in the biomass layer was found as non-uniform. Further parameters such as relative air humidity and the air temperature were measured and analysed, as well. It was concluded that the experimental biomass dryer with solar collector can work well in the conditions of the Central Moldova during the sunny period of the year.

Realization of a Solar Dryer Assisted by a Parabolic Dish Concentrator

2021 ◽  
Vol 406 ◽  
pp. 192-199
Author(s):  
Abdeldjalil Laouini ◽  
Boubaker Benhaou ◽  
Kamel Aoues ◽  
Abdelmalek Atia
Keyword(s):  
Food Products ◽  
Drying Time ◽  
Solar Dryer ◽  
Parabolic Dish ◽  
Parabolic Dish Concentrator ◽  
Drying Technology ◽  
Drying Chamber

Many studies have been conducted in the field of drying technology. The traditional dryingmethods are considered less effective and time consuming. The present study aims to develop the indirect solar dryer for agro-food products from El-Oued region (South-East of Algeria). The dryer is assisted by a parabolic dish concentrator to improve its performances through increasing its temperature and decreasing drying time. the realized solar dryer was tested on the red chilies during April 2018, the temperature in the drying chamber is reached intoxicating 55 °C with a drying time of 5 h.

scholarly journals Solar Drying Kinetics of Cass Ava Slices in a Mixed Flow Dryer

2015 ◽  
Vol 18 (4) ◽  
pp. 102-107 ◽  
Author(s):  
Olawale Usman Dairo ◽  
Adewole Ayobami Aderinlewo ◽  
Olayemi Johnson Adeosun ◽  
Ibukun Adekola Ola ◽  
Tolulope Salaudeen
Keyword(s):  
Diffusion Mechanism ◽  
Coefficient Of Determination ◽  
Drying Time ◽  
Drying Characteristics ◽  
Solar Dryer ◽  
Thin Layer Drying ◽  
Chamber Temperature ◽  
Drying Models ◽  
Kinetics Of ◽  
Drying Curve

Abstract Drying characteristics of cassava slices was investigated in a mixed mode natural convection solar dryer to obtain a suitable mathematical model describing the drying. The average drying chamber temperature was between 34 ±2 °C and 50 ±1.8 °C, while 10 commonly used thin layer drying models were used for drying curve modelling. Coefficient of determination (R2) and root mean square error (RMSE) were used to determine the models performances. The drying curve of cassava slices showed a reduction of moisture content with increased drying time in the solar dryer, and the variation of moisture ratio exponentially decreased with increased drying time. The Midilli and Logarithmic models showed better fit to the experimental drying data of cassava slices. As compared with other models tested, there were no significant differences (p >0.05) in the R2 values obtained for the Midilli and Logarithmic models; hence, the Logarithmic model was preferable because of the lower RMSE. The diffusion mechanism could be used to describe the drying of cassava slices that was found to be in the falling rate period. A diffusion coefficient (Deff) of 1.22 × 10-8 m2 s-1 was obtained, which was within the established standard for food products.

scholarly journals Energy Analysis of a Hybrid Solar Dryer for Drying Coffee Beans

2020 ◽  
Vol 9 (1) ◽  
pp. 131-139
Author(s):  
Suherman Suherman ◽  
Hasri Widuri ◽  
Shelyn Patricia ◽  
Evan Eduard Susanto ◽  
Raafi Jaya Sutrisna
Keyword(s):  
Moisture Content ◽  
Solar Collector ◽  
Energy Analysis ◽  
Initial Moisture Content ◽  
Solar Drying ◽  
Drying Method ◽  
Drying Time ◽  
Solar Dryer ◽  
Coffee Beans ◽  
Drying Chamber

In this study, hybrid solar drying of coffee beans was performed, and energy analysis was carried out, to assess the system’s performance, in terms of energy efficiency, compared to solar drying and the open sun drying method. The dryer has three compartments: solar collector for collecting solar radiation, drying chamber, and a Liquid Petroleum Gas burner, which acted as an auxiliary heater to assist the thermal energy. The drying chamber has four trays for placing the dried product. The initial moisture content of coffee beans was 54.23% w.b and was reduced to the final moisture content between 11-12% w.b. The coffee beans dried faster when subjected to the solar hybrid drying method, compared to other methods, with the dryer temperature of 40°C, 50°C, and 60°C. Results indicated that the coffee beans’ drying times varied from 10 to 14 hours. However, at temperature 50°C and 60°C for the 1st tray, the water content was reduced more rapidly compared to the other tray. From the results of this study, we can see the different efficiency of solar collector that shows of 54.15% at variable temperature 60°C for drying time 12:00 to 14:00 p.m for hybrid solar drying and for the solar drying process is 50.07% at the range of drying time 12:00 to 14:00 p.m. Mathematical modelling shows that Page model is the most suitable for describing the coffee beans’ drying behaviour using a hybrid solar dryer. The effective diffusivity values found in this experiment are all in the acceptable range for most agricultural products. ©2020. CBIORE-IJRED. All rights reserved

Performance of a Solar Drying System Driven by a Hybrid Power System

2012 ◽  
Vol 455-456 ◽  
pp. 139-146
Author(s):  
Hao Zhong ◽  
Zhi Min Li ◽  
Tong Wu ◽  
Ming Jiu Yu ◽  
Run Sheng Tang
Keyword(s):  
Power System ◽  
Early Stage ◽  
Initial Moisture Content ◽  
Agricultural Products ◽  
Solar Drying ◽  
Test Results ◽  
Drying Time ◽  
Drying System ◽  
Drying Chamber

To increase the production and improve the quality of dried agricultural products, a new drying system with a hybrid driving power system was developed and tested. The system with total collector area of 100m2 is consisted of 10 drying units and each of them is consisted of 5 identical air collectors and a greenhouse-like drying chamber. Each of collectors in the system is equipped with a DC fan, powered by either 120W solar modules or a 300W wind turbine, and an AC fan, directly powered by the electricity from grid. Such drying system can operate in all time of any day and avoid any possible spoilage of dried products as found in conventional solar dryers due to the formation of mould on the surface of dried materials in the events of consecutive rainy days. Field test for the drying of 9 fruits was conducted from November to December in 2005. The results indicated that the system was very effective for the drying of fruits and the solar drying time for most of the materials to be investigated was only one third of that required in the natural sun drying. Test results also showed that the nocturnal ventilation of drying chambers at the early stage of drying exercise was necessary for materials with high initial moisture content in order to further shorten the solar drying time.

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